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1.
  • Eriksson [Engvall], Gunilla, 1976- (författare)
  • The intelligence discourse : the Swedish military intelligence (MUST) as a producer of knowledge
  • 2013
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The Swedish Military Intelligence and Security Directorate (MUST) is a producer of knowledge, a knowledge that is fundamental for decisionmaking in foreign and security policy. The intelligence knowledge production is often held as objective, value neutral, and with the intention of ‘speaking truth onto power’. However, this study holds that such a perspective on intelligence knowledge production calls for a revision. Hence, the overall purpose of this study is to examine the characteristics of knowledge in intelligence analysis and also to investigate how that knowledge is affected by the social context of its production, the military intelligence service. The source material is of three kinds; first texts and documents, second interviews with intelligence analysts and managers, and third observations of seminars and meetings during the production process of estimates.The results are that there is a strong presence of an implicit interpretive framework that continuously influences and guides the knowledge production and thereby makes the knowledge dependent on one specific perspective contrary to the intentional objectivity within the intelligence service. Further, the study reveals that the social and discursive practices for intelligence knowledge production include a ‘logic of appropriateness’ suggesting the presence of a structured Denkkollektiv with a structured Denkstil. The actions and choices of the individuals are transformed to create conformity to the norms within the social discursive practices. Thus, the inherited frame of interpretation, as well as the socialised norm of staying within the existing accepted frames ofthinking and acting ends up to the stability and duration of the not always accurate and fruitful Denkstil.At the core of political science resides the question of how policy is shaped. Even though this study has focused merely on one organisation in a specific policy field in one country it brings insights to the knowledge and policy nexus.
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2.
  • Kvernby, Sofia, et al. (författare)
  • Simultaneous three-dimensional myocardial T1 and T2 mapping in one breath hold with 3D-QALAS
  • 2014
  • Ingår i: Journal of Cardiovascular Magnetic Resonance. - : Springer Science and Business Media LLC. - 1097-6647 .- 1532-429X. ; 16:102
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Quantification of the longitudinal- and transverse relaxation time in the myocardium has shown to provide important information in cardiac diagnostics. Methods for cardiac relaxation time mapping generally demand a long breath hold to measure either T1 or T2 in a single 2D slice. In this paper we present and evaluate a novel method for 3D interleaved T1 and T2 mapping of the whole left ventricular myocardium within a single breath hold of 15 heartbeats.METHODS: The 3D-QALAS (3D-quantification using an interleaved Look-Locker acquisition sequence with T2 preparation pulse) is based on a 3D spoiled Turbo Field Echo sequence using inversion recovery with interleaved T2 preparation. Quantification of both T1 and T2 in a volume of 13 slices with a resolution of 2.0x2.0x6.0 mm is obtained from five measurements by using simulations of the longitudinal magnetizations Mz. This acquisition scheme is repeated three times to sample k-space. The method was evaluated both in-vitro (validated against Inversion Recovery and Multi Echo) and in-vivo (validated against MOLLI and Dual Echo).RESULTS: In-vitro, a strong relation was found between 3D-QALAS and Inversion Recovery (R = 0.998; N = 10; p < 0.01) and between 3D-QALAS and Multi Echo (R = 0.996; N = 10; p < 0.01). The 3D-QALAS method showed no dependence on e.g. heart rate in the interval of 40-120 bpm. In healthy myocardium, the mean T1 value was 1083 ± 43 ms (mean ± SD) for 3D-QALAS and 1089 ± 54 ms for MOLLI, while the mean T2 value was 50.4 ± 3.6 ms 3D-QALAS and 50.3 ± 3.5 ms for Dual Echo. No significant difference in in-vivo relaxation times was found between 3D-QALAS and MOLLI (N = 10; p = 0.65) respectively 3D-QALAS and Dual Echo (N = 10; p = 0.925) for the ten healthy volunteers.CONCLUSIONS: The 3D-QALAS method has demonstrated good accuracy and intra-scan variability both in-vitro and in-vivo. It allows rapid acquisition and provides quantitative information of both T1 and T2 relaxation times in the same scan with full coverage of the left ventricle, enabling clinical application in a broader spectrum of cardiac disorders.
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  • Rademakers, Frank, et al. (författare)
  • Determining optimal noninvasive parameters for the prediction of left ventricular remodeling in chronic ischemic patients
  • 2013
  • Ingår i: Scandinavian Cardiovascular Journal. - : Informa Healthcare. - 1401-7431 .- 1651-2006. ; 47:6, s. 329-334
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives. DOPPLER-CIP aims to determine the optimal noninvasive parameters (myocardial function, perfusion, ventricular blood flow, cell integrity) and methodology (ergometry, echocardiography, scintigraphy, MRI) in a given ischemic substrate that best predicts the impact of an intervention (or the lack thereof) on adverse morphological ventricular remodeling and functional recovery. Moreover, the relative predictive value of each of these parameters, in respect to the cost of extracting this information in order to enable optimization of cost-effectiveness for improved health care, will be determined by this project. Design. DOPPLER-CIP is a multi-center registry study. All patients with ischemic heart disease included in this study undergo at least two noninvasive stress imaging examinations at baseline. The presence/or absence of left ventricular (LV) remodeling will be assessed after a follow-up of 2 years, during which all cardiac events will be registered. Results. 676 patients were included. Currently, baseline data analysis is almost finished and the follow-up is ongoing. Conclusions. After completion, DOPPLER-CIP will provide evidence-based guidelines toward the most effective use of cardiac imaging in the chronically ischemic heart disease patient. The study will generate information, knowledge, and insight into the new imaging methodologies and into the pathophysiology of chronic ischemic heart disease.
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  • Aneq Åström, Meriam, et al. (författare)
  • Determination of right ventricular volume and function using multiple axially rotated MRI slices
  • 2011
  • Ingår i: Clinical Physiology and Functional Imaging. - : Blackwell Publishing Ltd. - 1475-0961 .- 1475-097X. ; 31:3, s. 233-239
  • Tidskriftsartikel (refereegranskat)abstract
    • Pandgt;Background: The conventional magnetic resonance imaging (MRI) method for right ventricular (RV) volume and motion, using short-axis (SA) orientation, is limited by RV anatomy and shape. We suggest an orientation based on six slices rotated around the long axis of the RV, rotated long axis (RLA). Materials and methods: Three phantoms were investigated in SA and RLA using cine balanced steady-state free precession MRI. Volumes were calculated based on segmentation and checked against true volumes. In 23 healthy male volunteers, we used six long-axis planes from the middle of the tricuspid valve to the RV apex, rotated in 30 degrees increments. For comparison, short-axis slices were acquired. Imaging parameters were identical in both acquisitions. Results: Right ventricular end-diastolic (EDV), end-systolic (ESV) and stroke volumes (SV) determined in the RLA 179 center dot 1 +/- 29 center dot 3; 80 center dot 1 +/- 17 center dot 1; 99 center dot 3 +/- 16 center dot 9 ml and in the SA were 174 center dot 0 +/- 21 center dot 1; 78 center dot 8 +/- 13 center dot 6; 95 center dot 3 +/- 14 center dot 5 ml with P-values for the difference from 0 center dot 17 to 0 center dot 64 (ns). Interobserver variability ranged between 3 center dot 2% and 6 center dot 6% and intraobserver variability between 2 center dot 8% and 6 center dot 8%. In SA views, consensus for the definition of the basal slice was necessary in 39% of the volunteers for whom the average volume change was 20% in ESV and 10% in EDV. Conclusions: The RLA method results in better visualization and definition of the RV inflow, outflow and apex. Accurate measurement of RV volumes for diagnosis and follow-up of cardiac diseases are enhanced by the RLA orientation, even though additional acquisition time is required.
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6.
  • Aneq Åström, Meriam, et al. (författare)
  • Novel plakophilin2 mutation. Three generation family with arrhythmogenic right ventricular cardiomyopathy
  • 2012
  • Ingår i: Scandinavian Cardiovascular Journal. - : Informa Healthcare. - 1401-7431 .- 1651-2006. ; 46:2, s. 72-75
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives: The autosomal dominant form of arrhythmogenic right ventricular cardiomyopathy (ARVC)has been linked to mutations in desmosomal proteins. Different studies have shown that amutation in plakophilin-2 (PKP 2) is a frequent genetic cause for ARVC. We describe a newmutation in the PKP2 gene, the genotype-phenotype variation in this mutation and its clinicalconsequences. Design: Individuals in a three generation family were investigated after the sudden cardiac death of a young male. Clinical evaluation, electrocardiography, echocardiography, magnetic resonance imaging, endomyocardial biopsy and genetic testing were performed. Results: A novel heterozygote mutation, a c.368G>A transition, located in exon 3 of the PKP2 gene was found (p.Trp123X). The phenotype was characterized by arrhythmia at an early age in some individuals, with mild abnormalities on imaging. However a relative carrying this mutation, with positive findings on endomyocardial biopsy had an otherwise normal phenotype, for 16 years, whereas a relative fulfilling the modified Task Force Criteria for ARVC turned out to be a non-carrier. Conclusions: This shows the variable penetrance and phenotypic expression in ARVC and highlights the need of genetic testing as well as a thorough phenotype examination as a part of the investigations in ARVC pedigrees.
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  • Calcutteea, Avin, 1978- (författare)
  • New insights in the assessment of right ventricular function : an echocardiographic study
  • 2013
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Background:  The right ventricle (RV) is multi-compartmental in orientation with a complex structural geometry. However, assessment of this part of the heart has remained an elusive clinical challenge. As a matter of fact, its importance has been underestimated in the past, especially its role as a determinant of cardiac symptoms, exercise capacity in chronic heart failure and survival in patients with valvular disease of the left heart. Evidence also exists that pulmonary hypertension (PH) affects primarily the right ventricular function. On the other hand, previous literature suggested that severe aortic stenosis (AS) affects left ventricular (LV) structure and function which partially recover after aortic valve replacement (AVR). However, the impact of that on RV global and segmental function remains undetermined. Objectives: We sought to gain more insight into the RV physiology using 3D technology, Speckle tracking as well as already applicable echocardiographic measures. Our first aim was to assess the normal differential function of the RV inflow tract (IT), apical and outflow tract (OT) compartments, also their interrelations and the response to pulmonary hypertension. We also investigated the extent of RV dysfunction in severe AS and its response to AVR. Lastly, we studied the extent of global and regional right ventricular dysfunction in patients with pulmonary hypertension of different aetiologies and normal LV function.Methods: The studies were performed on three different groups; (1) left sided heart failure with (Group 1) and without (Group 2) secondary pulmonary hypertension, (2) severe aortic stenosis and six months post AVR and (3) pulmonary hypertension of different aetiologies and normal left ventricular function. We used 3D, speckle tracking echocardiography and conventionally available Doppler echocardiographic transthoracic techniques including M-mode, 2D and myocardial tissue Doppler. All patients’ measurements were compared with healthy subjects (controls). Statistics were performed using a commercially available SPSS software.Results:1-  Our RV 3D tripartite model was validated with 2D measures and eventually showed strong correlations between RV inflow diameter (2D) and end diastolic volume (3D) (r=0.69, p<0.001) and between tricuspid annular systolic excursion (TAPSE) and RV ejection fraction (3D) (r=0.71, p<0.001). In patients (group 1 & 2) we found that the apical ejection fraction (EF) was less than the inflow and outflow (controls:  p<0.01 & p<0.01, Group 1:  p<0.05 & p<0.01 and Group 2: p<0.05 & p<0.01, respectively). Ejection fraction (EF) was reduced in both patient groups (p<0.05 for all compartments). Whilst in controls, the inflow compartment reached the minimum volume 20 ms before the outflow and apex, in Group 2 it was virtually simultaneous. Both patient groups showed prolonged isovolumic contraction (IVC) and relaxation (IVR) times (p<0.05 for all). Also, in controls, the outflow tract was the only compartment where the rate of volume fall correlated with the time to peak RV ejection (r = 0.62, p = 0.03). In Group 1, this relationship was lost and became with the inflow compartment (r = 0.61, p = 0.01). In Group 2, the highest correlation was with the apex (r=0.60, p<0.05), but not with the outflow tract.2- In patients with severe aortic stenosis, time to peak RV ejection correlated with the basal cavity segment (r = 0.72, p<0.001) but not with the RVOT. The same pattern of disturbance remained after 6 months of AVR (r = 0.71, p<0.001). In contrast to the pre-operative and post-operative patients, time to RV peak ejection correlated with the time to peak outflow tract strain rate (r = 0.7, p<0.001), but not with basal cavity function. Finally in patients, RVOT strain rate (SR) did not change after AVR but basal cavity SR fell  (p=0.04).3- In patients with pulmonary hypertension of different aetiologies and normal LV function, RV inflow and outflow tracts were dilated (p<0.001 for both). Furthermore, TAPSE (p<0.001), inflow velocities (p<0.001), basal and mid-cavity strain rate (SR) and longitudinal displacement (p<0.001 for all) were all reduced. The time to peak systolic SR at basal, mid-cavity (p<0.001 for both) and RVOT (p=0.007) was short as was that to peak displacement (p<0.001 for all). The time to peak pulmonary ejection correlated with time to peak SR at RVOT (r=0.7, p<0.001) in controls, but with that of the mid cavity in patients (r=0.71, p<0.001). Finally, pulmonary ejection acceleration (PAc) was faster (p=0.001) and RV filling time shorter in patients (p=0.03) with respect to controls.Conclusion: RV has distinct features for the inflow, apical and outflow tract compartments, with different extent of contribution to the overall systolic function. In PH, RV becomes one dyssynchronous compartment which itself may have perpetual effect on overall cardiac dysfunction. In addition, critical aortic stenosis results in RV configuration changes with the inflow tract, rather than outflow tract, determining peak ejection. This pattern of disturbance remains six month after valve replacement, which confirms that once RV physiology is disturbed it does not fully recover. The findings of this study suggest an organised RV remodelling which might explain the known limited exercise capacity in such patients. Furthermore, in patients with PH of different aetiologies and normal LV function, there is a similar pattern of RV disturbance. Therefore, we can conclude that early identification of such changes might help in identifying patients who need more aggressive therapy early on in the disease process.
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12.
  • Dyverfeldt, Petter, et al. (författare)
  • Hemodynamic aspects of mitral regurgitation assessed by generalized phase-contrast MRI
  • 2011
  • Ingår i: Journal of Magnetic Resonance Imaging. - : John Wiley and Sons. - 1053-1807 .- 1522-2586. ; 33:3, s. 582-588
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: Mitral regurgitation creates a high velocity jet into the left atrium (LA), contributing both volume andpressure; we hypothesized that the severity of regurgitation would be reflected in the degree of LA flowdistortion.Material and Methods: Three-dimensional cine PC-MRI was applied to determine LA flow patterns andturbulent kinetic energy (TKE) in seven subjects (five patients with posterior mitral leaflet prolapse, two normalsubjects). In addition, the regurgitant volume and the time-velocity profiles in the pulmonary veins weremeasured.Results: The LA flow in the mitral regurgitation patients was highly disturbed with elevated values of TKE.Peak TKE occurred consistently at late systole. The total LA TKE was closely related to the regurgitant volume.LA flow patterns were characterized by a pronounced vortex in proximity to the regurgitant jet. In some patients,pronounced discordances were observed between individual pulmonary venous inflows, but these could not berelated to the direction of the flow jet or parameters describing global LA hemodynamics.Conclusion: PC-MRI permits investigations of atrial and pulmonary vein flow patterns and TKE in significantmitral regurgitation, reflecting the impact of the highly disturbed blood flow that accompanies this importantvalve disease.
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13.
  • Engvall, Jan, et al. (författare)
  • Adenosine stress myocardial perfusion detected with CT compared with attenuation-corrected SPECT
  • 2011
  • Ingår i: EUROPEAN HEART JOURNAL SUPPLEMENTS. - : Oxford University Press. ; , s. A31-A31
  • Konferensbidrag (refereegranskat)abstract
    • Purpose: To asses adenosine stress myocardial perfusion by cardiac CT and compare with simultaneously performed attenuation corrected SPECT.Methods: 11 patients, 9 men and 2 women >2months post primary PCI, with manifest myocardial damage and remaining stenoses in the coronary circulation, were studied with myocardial perfusion CT under vasodilatory stress. The investigation started with a topogram followed by a testbolus of iodine whereafter the coronary artery study was performed in sequence mode. Adenosine was then infused for at least five minutes at the standard rate of 140ug/kg/min. After three minutes, 6 MBq/kg of 99mTc-tetrofosmin was injected immediately followed by 80ml iodine contrast. The wash-in of iodine was monitored by CT scanning of a 7cm long cardiac volume segment every other second for 22s. One hour after the CT scan, myocardial SPECT was performed. Scanning required the patients to tolerate breath holding for 22s, have a heart rate <80/min and body weight <85kg, and their kidney function should allow 140ml 370mg iodine contrast to be given.Results: All 11 patients tolerated the full adenosine infusion and scanning was successful. One patient could not be analyzed due to noisy images. In two patients, the limited scanning volume did not cover the entire base of the heart. Three patients had no defect on SPECT. Patients with a defect had on average myocardial blood flow 80ml/100ml tissue/min in the defect area and 142ml in the segments with the highest perfusion, while patients without defect had 98 and 141ml, respectively.Conclusion: Peak myocardial perfusion may be determined with CT under adenosine stress and compared with attenuation corrected SPECT. Initial experience shows that the method is sensitive to timing of bolus, to noisy images and results may diverge from those obtained with SPECT.
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14.
  • Eriksson, Jonatan, et al. (författare)
  • Quantification of presystolic blood flow organization and energetics in the human left ventricle
  • 2011
  • Ingår i: AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY. - : AMER PHYSIOLOGICAL SOC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA. - 0363-6135 .- 1522-1539. ; 300:6, s. H2135-H2141
  • Tidskriftsartikel (refereegranskat)abstract
    • Intracardiac blood flow patterns are potentially important to cardiac pumping efficiency. However, these complex flow patterns remain incompletely characterized both in health and disease. We hypothesized that normal left ventricular (LV) blood flow patterns would preferentially optimize a portion of the end-diastolic volume (LVEDV) for effective and rapid systolic ejection by virtue of location near and motion towards the LV outflow tract (LVOT). Three-dimensional cine velocity and morphological data were acquired in 12 healthy persons and 1 patient with dilated cardiomyopathy using MRI. A previously validated method was used for analysis in which the LVEDV was separated into four functional flow components based on the bloods locations at the beginning and end of the cardiac cycle. Each components volume, kinetic energy (KE), site, direction, and linear momentum relative to the LVOT were calculated. Of the four components, the LV inflow that passes directly to outflow in a single cardiac cycle (Direct Flow) had the largest volume. At the time of isovolumic contraction, Direct Flow had the greatest amount of KE and the most favorable combination of distance, angle, and linear momentum relative to the LVOT. Atrial contraction boosted the late diastolic KE of the ejected components. We conclude that normal diastolic LV flow creates favorable conditions for ensuing ejection, defined by proximity and energetics, for the Direct Flow, and that atrial contraction augments the end-diastolic KE of the ejection volume. The correlation of Direct Flow characteristics with ejection efficiency might be a relevant investigative target in cardiac failure.
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  • Eriksson, Jonatan, et al. (författare)
  • Semi-automatic quantification of 4D left ventricular blood flow
  • 2010
  • Ingår i: JOURNAL OF CARDIOVASCULAR MAGNETIC RESONANCE. - 1097-6647. ; 12:9
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The beating heart is the generator of blood flow through the cardiovascular system. Within the hearts own chambers, normal complex blood flow patterns can be disturbed by diseases. Methods for the quantification of intra-cardiac blood flow, with its 4D (3D+time) nature, are lacking. We sought to develop and validate a novel semi-automatic analysis approach that integrates flow and morphological data. Method: In six healthy subjects and three patients with dilated cardiomyopathy, three-directional, three-dimensional cine phase-contrast cardiovascular magnetic resonance (CMR) velocity data and balanced steady-state free-precession long- and short-axis images were acquired. The LV endocardium was segmented from the short-axis images at the times of isovolumetric contraction (IVC) and isovolumetric relaxation (IVR). At the time of IVC, pathlines were emitted from the IVC LV blood volume and traced forwards and backwards in time until IVR, thus including the entire cardiac cycle. The IVR volume was used to determine if and where the pathlines left the LV. This information was used to automatically separate the pathlines into four different components of flow: Direct Flow, Retained Inflow, Delayed Ejection Flow and Residual Volume. Blood volumes were calculated for every component by multiplying the number of pathlines with the blood volume represented by each pathline. The accuracy and inter- and intra-observer reproducibility of the approach were evaluated by analyzing volumes of LV inflow and outflow, the four flow components, and the end-diastolic volume. Results: The volume and distribution of the LV flow components were determined in all subjects. The calculated LV outflow volumes [ml] (67 +/- 13) appeared to fall in between those obtained by through-plane phase-contrast CMR (77 +/- 16) and Doppler ultrasound (58 +/- 10), respectively. Calculated volumes of LV inflow (68 +/- 11) and outflow (67 +/- 13) were well matched (NS). Low inter- and intra-observer variability for the assessment of the volumes of the flow components was obtained. Conclusions: This semi-automatic analysis approach for the quantification of 4D blood flow resulted in accurate LV inflow and outflow volumes and a high reproducibility for the assessment of LV flow components.
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16.
  • Forsberg, Lena M, et al. (författare)
  • Differences in recovery of left and right ventricular function following aortic valve interventions : a longitudinal echocardiographic study in patients undergoing surgical, transapical or transfemoral aortic valve implantation
  • 2013
  • Ingår i: Catheterization and cardiovascular interventions. - : Wiley. - 1522-1946 .- 1522-726X. ; 82:6, s. 1004-1014
  • Tidskriftsartikel (refereegranskat)abstract
    • ObjectivesTo evaluate longitudinal left and right ventricular function (LVF and RVF) after transcatheter aortic valve implantation (TAVI) as compared to surgical aortic valve replacement (SAVR) and LVF and RVF after TAVI by the transfemoral (TF) or transapical (TA) approach.BackgroundKnowledge about differences in recovery of LVF and RVF after TAVI and SAVR is scarce.MethodsSixty patients (age 81 ± 7 years, logistic EuroSCORE 16 ± 10%), undergoing TAVI (TF: n = 35 and TA: n  = 25), were examined by echocardiography including atrioventricular plane displacement (AVPD) and peak systolic velocities (PSV) by tissue Doppler at basal RV free wall, LV lateral wall and septum preprocedurally, 7 weeks and 6 months postprocedurally. Twenty-seven SAVR patients were matched to 27 TAVI patients by age, gender and LVF.ResultsEarly postintervention, TAVI patients had improved longitudinal LVF. However, when analyzed separately, only TF, but not TA patients, had improved LV lateral and septal AVPD and PSV (all P ≤ 0.01). All TAVI patients, as well as the TF and TA group had unchanged longitudinal LVF between the early and late follow-ups (all P > 0.05). The SAVR group had higher septal LVF than the matched TAVI group preprocedurally, while postoperatively this difference was diminished. Longitudinal RVF was better in the TF group than in the TA group pre- and postprocedurally. Although the SAVR group had superior longitudinal RVF preoperatively, this was inferior to TAVI postoperatively.Conclusions Postprocedural longitudinal LVF and RVF in patients undergoing TF-TAVI, TA-TAVI, or SAVR differ considerably. Preservation of longitudinal RVF after TAVI might influence the selection of aortic valve intervention in the future.
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  • Forsberg, Lena M, et al. (författare)
  • Left and right ventricular function in aortic stenosis patients 8 weeks post-transcatheter aortic valve implantation or surgical aortic valve replacement
  • 2011
  • Ingår i: European Journal of Echocardiography. - : Oxford University Press (OUP). - 1525-2167 .- 1532-2114. ; 12:8, s. 603-611
  • Tidskriftsartikel (refereegranskat)abstract
    • Aims Knowledge of longitudinal left and right ventricular (LV and RV) function after transcatheter aortic valve implantation (TAVI) is scarce. We hypothesized that the longitudinal systolic biventricular function in aortic stenosis (AS) patients is affected differently by TAVI and surgical aortic valve replacement (SAVR). less thanbrgreater than less thanbrgreater thanMethods and results Thirty-three AS patients (all-TAVI group, age 81 +/- 9 years, 18 female), with EuroSCORE 18 +/- 9%, were accepted for TAVI. Seventeen of these patients were matched (by gender, age, and LV function) to 17 patients undergoing SAVR. Conventional echocardiographic parameters, systolic atrioventricular plane displacement (AVPD) at standard sites and peak systolic velocity (PSV) by pulsed tissue Doppler at basal RV free wall, LV lateral wall, and septum were studied before and 8 weeks after the procedure. Procedural success was 100%, and 30-day mortality 9%. In all TAVI patients, AVPD(lateral), PSV(lateral), AVPD(septal), and PSV(septal) increased (P andlt; 0.001, 0.003, 0.006 and 0.002). When studying the matched patients postoperatively, both the SAVR and TAVI patients had increased PSV(lateral) and AVPD(lateral) (SAVR: P = 0.03 and P = 0.04, TAVI: P = 0.04 and P = 0.01). The PSV(RV) increased in the all-TAVI group (P = 0.007), while the AVPD(RV) was unchanged. SAVR patients had decreased AVPD(RV) (P = 0.001) and PSV(RV) (P = 0.004), while the matched TAVI patients had unchanged RV function parameters. less thanbrgreater than less thanbrgreater thanConclusion An improvement in regional longitudinal LV function in the septal and lateral wall could be seen after TAVI. Among the matched patients, both the TAVI and SAVR patients seemed to improve LV function in the lateral wall. RV systolic function increased in TAVI patients, but was impaired in the matched SAVR group at the 8-week follow-up.
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  • Franck, Niclas, et al. (författare)
  • Cardiovascular risk factors related to the PPARγ Pro12Ala polymorphism in patients with type 2 diabetes are gender dependent
  • 2012
  • Ingår i: Blood Pressure. - : Informa Healthcare. - 0803-7051 .- 1651-1999. ; 21:2, s. 122-127
  • Tidskriftsartikel (refereegranskat)abstract
    • The interaction of the PPARγ Pro12Ala polymorphism with diabetes and cardiovascular risk is controversial. We studied 173 women and 309 men in the observational CARDIPP trial in which determination of left ventricular mass, carotid intima-media thickness (IMT) and pulse wave velocity (PWV) were performed. Blood pressures were measured with 24-h ambulatory technique (ABP). Heterozygotes and homozygotes of Ala were defined as Ala in the analyses. Men with Ala-isoform displayed higher waist circumference (Ala: 107 ± 14 cm, Pro: 104 ± 11 cm, p = 0.045) and body weight (Ala: 95.7 ± 18 kg, Pro: 91.6 ± 14 kg, p = 0.042) than Pro-homozygotes. Men with ALA-isoform also showed higher systolic ABP levels (Ala: 134 ± 15 mmHg, Pro: 130 ± 14 mmHg, p = 0.004), whereas left ventricular mass index, IMT and PWV were unrelated to isoforms. In contrast, carotid–radial PWV was lower in women with the Ala-isoform (Ala: 7.9 ± 1.0 m/s, Pro: 8.5 ± 1.3 m/s, p = 0.01) and levels of apolipoprotein A1 were higher (Ala: 1.43 ± 0.27 g/l, Pro: 1.35 ± 0.17 g/l, p = 0.03). In conclusion, we found that men with type 2 diabetes having the Ala-isoform of PPARγ Pro12Ala had an unfavorable cardiovascular risk profile, whereas women with this isoform had lower carotid–radial PWV and higher apolipoprotein A1 levels suggesting a beneficial prognosis. These differences according to gender of the ALA isoform in type 2 diabetes deserve further attention.
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  • Gonzalez Garcia, Manuel Cruz, 1969- (författare)
  • The role of leptin in endothelial dysfunction and cardiovascular disease
  • 2013
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Objective:  Obesity has become the leading cause of mortality worldwide; however, the fundamental pathophysiology underlying this association remains unclear. The discovery of adipokines, i.e., cytokines produced by adipose cells (adipocytes), revealed that adipose tissue is a highly endocrine organ, thus opening new lines of investigation. The prototypical adipokine leptin increases in obesity, and leptin receptors are found in vascular cells. However, results are contradictory regarding the role of leptin in vascular and endothelial functions. Leptin has been shown to elicit vasodilatation, but has also been linked with atherosclerotic and thrombotic disease. The main aim of the present thesis was to study the association of circulating levels of leptin with markers of endothelial function, and to analyze the effects of leptin infusion in vivo  on vasomotor function and endogenous fibrinolysis.Material:  Four associative studies and two interventional studies were conducted. The former included DISARM (studies 1 and 2), the PIVUS study (study 3), and the Scottish post-infarction study (study 4). The DISARM studies and study 4, respectively, recruited 20 men and 83 men and women with stable ischemic heart disease. Study 3 included a random sample of 1016 subjects (54% women, 70 years old) living in the community of Uppsala, Sweden. For the interventional studies (studies 5 and 6), 10 healthy men were recruited for each study.Methods:  In all studies, endothelial function was estimated based on forearm blood flow (FBF) as measured by strain-gauge venous occlusion plethysmography, at rest or during infusion of vasodilators. In study 3, additional measurement techniques were used, such as brachial ultrasound flow-mediated dilation (FMD) and the aortic augmentation index (AoAIx) by tonometry in the radial artery. Fibrinolytic status was estimated based on basal and stimulated levels of tissue plasminogen activator antigen (t-PA), and by assessment of the endothelial release of t-PA (net t-PA release). Plasma leptin levels were measured by radioimmunoassay. In the associative studies, endothelial function and fibrinolytic status were related to circulating plasma leptin levels. In the experimental studies, exogenous leptin was administered in the brachial artery and endothelial function was assessed by strain-gauge plethysmographyResults:  In elderly men and women, leptin was independently associated with decreased endothelial-dependent and -independent vasodilatation, reflecting disturbed endothelial function in resistance vessels. This association was attenuated after adjustment for BMI, and when analyzed among subjects with high plasma leptin levels. FMD (a measure of endothelial function in conduit vessels) was not associated with leptin. Exogenous leptin infusion did not alter vasomotor tone, but the endothelium-dependent and -independent vasodilatation was impaired during concomitant infusion of leptin and vasodilators. Infused leptin in the forearm did not affect blood pressure or pulse rate. Chronic hyperleptinemia, but not acutely induced hyperleptinemia, was associated with release of endothelial tissue plasminogen activator (net t-PA).Conclusions:  In humans, leptin was associated with impaired vasodilatation. However, this relationship was blunted after adjustment for BMI, suggesting that leptin could be the mediator between obesity and impaired vascular function. Furthermore, the observed lack of association in hyperleptinemic subjects may reflect a state of leptin resistance. The experimental result showing attenuated vascular reactivity following leptin infusion is in accordance with the results of the associative studies. The augmented net t-PA release in patients with chronic hyperleptinemia may indicate a state of “vascular activation,” which was not observed in healthy endothelium during a short period of leptin infusion. This thesis addresses several controversial issues regarding the action of leptin on vascular tissue in humans. The final results indicate that the in vivo action of leptin on vascularity is complex and mediated by several mechanisms. Our findings suggest that leptin is an important mediator between obesity and endothelial dysfunction, and should stimulate further investigation of this matter.
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20.
  • Haraldsson, Henrik, 1977- (författare)
  • Assessment of Myocardial Function using Phase Based Motion Sensitive MRI
  • 2010
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Quantitative assessment of myocardial function is a valuable tool for clinical applications and physiological studies. This assessment can be acquired using phase based motion sensitive magnetic resonance imaging (MRI) techniques. In this thesis, the accuracy of these phase based motion sensitive MRI techniques is investigated, and modifications in acquisition and post-processing are proposed.The strain rate of the myocardium can be used to evaluate the myocardial function. However, the estimation of strain rate from the velocity data acquired with phase-contrast MRI (PC-MRI) is sensitive to noise. Estimation using normalized convolution showed, however, to reduce this sensitivity to noise and to minimize the influence of non-myocardial tissue which could impair the result.Strain of the myocardium is another measure to assess myocardial function. Strain can be estimated from the myocardial displacement acquired with displacement encoding with stimulated echo (DENSE). DENSE acquisition can be realized with several different encoding strategies. The choice of encoding scheme may make the acquisition more or less sensitive to different sources of error. Two potential sources of errors in DENSE acquisition are the influence of the FID and of  the off-resonance effects. Their influence on DENSE were investigated to determine suitable encoding strategies to reduce their influence and thereby improve the measurement accuracy acquired.The quality of the DENSE measurement is not only dependent on the accuracy, but also the precision of the measurement. The precision is affected by the SNR and thereby depends on flip angle strategies, magnetic field strength and spatial variation of the receiver coil sensitivity. A mutual comparison of their influence on SNR in DENSE was therefore performed and could serve as a guideline to optimize parameters for specific applications.The acquisition time is often an important factor, especially in clinical applications where it affects potential patient discomfort and patient through-put. A multiple-slice DENSE acquisition was therefore presented, which allows the acquisition of strain values according to the 16-segment cardiac model within a single breath-hold, instead of the conventional three breath-holds.The DENSE technique can also be adapted toward comprehensive evaluation of the heart in the form of full three-dimensional three-directional acquisition of the displacement. To estimate the full strain tensor from these data, a novel post-processing technique using a polynomial was investigated. The method yielded accurate results on an analytical model and \textit{in-vivo} strains obtained agreed with previously reported myocardial strains in normal volunteers.
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21.
  • Haraldsson, Henrik, 1977-, et al. (författare)
  • Influence of the FID and off-resonance effects in dense MRI
  • 2011
  • Ingår i: Magnetic Resonance in Medicine. - : Wiley. - 0740-3194 .- 1522-2594. ; 65:4, s. 1104-1112
  • Tidskriftsartikel (refereegranskat)abstract
    • Accurate functional measurement in cardiovascular diseases is important as inaccuracy may compromise diagnostic decisions. Cardiac function can be assessed using displacement encoding with stimulated echoes, resulting in three signal components. The free induction decay (FID), arising from spins undergoing T1-relaxation, is not displacement encoded and impairs the displacement acquired. Techniques for suppressing the FID exist; however, a residual will remain. The effect of the residual is difficult to distinguish and investigate in vitro and in vivo. In this work, the influence of the FID as well as of off-resonance effects is evaluated by altering the phase of the FID in relation to the stimulated echo. The results show that the FID and off-resonance effects can impair the accuracy of the displacement measurement acquired. The influence of the FID can be avoided by using an encoded reference. We therefore recommend the assessment of this influence of the FID for each displacement encoding with stimulated echoes protocol.
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22.
  • Jennersjö, Pär E., et al. (författare)
  • Circadian blood pressure variation in patients with type 2 diabetes - relationship to macro- and microvascular subclinical organ damage
  • 2011
  • Ingår i: Primary Care Diabetes. - : Elsevier. - 1751-9918 .- 1878-0210. ; 5:3, s. 167-173
  • Tidskriftsartikel (refereegranskat)abstract
    • AimsTo explore the association between nocturnal blood pressure (BP) dipper status and macro- and microvascular organ damage in type 2 diabetes.MethodsCross-sectional data from 663 patients with type 2 diabetes, aged 55–66 years, were analysed. Nurses measured office BP and ambulatory BP during 24 h. Individuals with ≥10% difference in nocturnal systolic blood pressure (SBP) relative to daytime values were defined as dippers. Non-dippers were defined as <10% nocturnal decrease in SBP. Estimated glomerular filtration rate (GFR) was calculated and microalbuminuria was measured by albumin:creatinine ratio (ACR). Aortic pulse wave velocity (PWV) was measured with applanation tonometry over the carotid and femoral arteries.ResultsWe identified 433 dippers and 230 subjects with a nocturnal non-dipping pattern. Nocturnal SBP dipping was independently of office SBP associated with decreased PWV (p = 0.008), lower ACR (p = 0.001) and NT-proBNP (p = 0.001) and increased GFR (p < 0.001).ConclusionsWe conclude that diurnal BP variation provides further information about early macro- and microvascular subclinical organ damage that goes beyond standardized office BP measurements in patients with type 2 diabetes.
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23.
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24.
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25.
  • Kindberg, Katarina, et al. (författare)
  • Myocardial strains from 3D displacement encoded magnetic resonance imaging
  • 2012
  • Ingår i: BMC Medical Imaging. - : BioMed Central. - 1471-2342. ; 12:9
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundThe ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE), make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however.MethodsWe propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor.ResultsThe proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations.ConclusionsStrain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts.
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26.
  • Kothapalli, VeeraVenkata Satyanarayana, 1985- (författare)
  • Ultrasound Contrast Agents Loaded with Magnetic Nanoparticles : Acoustic and Mechanical Characterization
  • 2013
  • Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The current methodologies in body scanning diagnostic uses different simultaneous imaging modalities like Ultrasound (US), magnetic resonance imaging (MRI), single photon emission tomography (SPECT) and positron emission tomography (PET). The field requires combination of different modalities for effective use in clinical diagnostics. Such incorporation of different modalities has already been achieved. For example, PET-CT hybrid scanner is designed to acquire align functional and anatomical images and recently US-MRI scanner has successfully shown to improve diagnosis of prostate cancer. The non ionizing radiation hybrid US-MRI is of great interest in health care industry. Further these US and MRI modalities uses different contrast agents like micro-sized gas bubbles (MBs) encapsulated by surfactant for US and superparamagnetic nanoparticles for MRI imaging modalities to further enables new diagnostic opportunities and therapeutic applications. Recently in our 3MiCRON project, we have developed the multimodal contrast agent that could be supported for both US and MRI. This was achieved by coating the magnetic nanoparticles to the poly vinyl alcohol (PVA) surfactant shelled MBs. The nanoparticles in the shell effect the structure can alter the MBs performance as an ultrasound contrast agent. The present thesis is conducted to examine the acoustic and mechanical properties of such multimodal contrast agents.These multimodal contrast agents were prepared by coating the surface of PVA-shelled MBs by two following strategies: (1) The superparamagnetic iron oxide (Fe3O4) nano-particles (SPIONs) were chemically anchored to the surface of poly vinyl alcohol (PVA) shelled MBs namely MBs-chem and (2) in the second strategy the SPIONs were physical entrapped into the PVA shell while formation of PVA surface on the gas bubble were named as MBs-phys. To understand the scattering efficiency and viscoelastic properties of these modified agents, we investigated the backscattering power, attenuation coefficient and phase velocity measurements. Our acoustic experimental results indicate that both the modified MBs and non-modified plain PVA-shelled ultrasound contrast agents have the same echogenic response. The investigation of mechanical properties of modified MBs revealed that the attached SPIONs on the PVA shell has reduced the stiffness of MBs-chem shell, while, the SPIONs inside the shell has increased MBs-phys stiffness. As a result, MBs-chem exhibits soft shell behavior under ultrasound exposure than both MBs-phys. Finally, the images were obtained through the MRI investigations at the department of Radiology, Karolinksa Institute, has demonstrated that both MB types have enough magnetic susceptibility that further provides good detectability in vitro and in vivo. As an outlook, the modified magnetic gas bubbles, i.e. both MBs-chem and MBs-phys can be proposed as a potential contrast agent for both US and MR imaging and can be further utilized in potential therapeutic applications.
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27.
  • Koulaouzidis, George, 1972- (författare)
  • Investigation of the origin of the coronary artery calcification process and its relationship to the atherosclerotic cardiovascular disease
  • 2013
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The objectives of this thesis are: a) To examine racial/ethnic differences in coronary artery calcification (CAC) and CAD, between symptomatic South Asians and Caucasians, matched for age, gender and conventional cardiovascular risk factors, b) To assess, using a meta-analysis model, the natural history of and stability of measurements of coronary artery calcium scoring (CACs) based on data collected from two large published trials: St Francis and EBEAT, c) To investigate the prevalence of coronary artery calcification in individuals with CT evidence for AVC, mitral valve calcification (MAC) or of both of them (AVC+MAC), d) To assess any potential association between premature CAD (<55 years in first-degree male relatives and <65 years in first-degree female relatives) and CAC in a large cohort of asymptomatic individuals.We found that coronary artery calcification is more extensive and diffuse in symptomatic patients of South Asian ethnic origin as compared to Caucasians, despite similar conventional risk factors for CAD. This is more evident in those >50 years of age, suggesting potential genetic or other risk factors yet to be determined. The natural history of coronary artery calcification was overtime progression in the majority of subjects, irrespective of gender. The higher variability in RCA measurements could be related to the low baseline CACs or exaggerated movement of the right side atrioventricular ring, whereas those for LCA brances are influenced by the branch allocation of the CACs. Valve calcification is not isolated but involve also and the coronary arteries. The presence of calcification in the aortic valve or combined aortic and mitral valves predicted coronary artery calcification. Additionally patients in whom both valves have become calcified tend to have severe coronary artery calcification. And finally, there is no relationship between the prevalence and extent of coronary artery calcification and the presence of family history of coronary heart disease in asymptomatic individuals with none of the conventional risk factors for atherosclerosis.
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28.
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29.
  • Lantz, Jonas, et al. (författare)
  • Numerical and experimental assessment of turbulent kinetic energy in an aortic coarctation
  • 2013
  • Ingår i: Journal of Biomechanics. - : Elsevier. - 0021-9290 .- 1873-2380. ; 46:11, s. 1851-1858
  • Tidskriftsartikel (refereegranskat)abstract
    • The turbulent blood flow through an aortic coarctation in a 63-year old female patient was studied experimentally using magnetic resonance imaging (MRI), and numerically using computational fluid dynamics (CFD), before and after catheter intervention. Turbulent kinetic energy (TKE) was computed in the numerical model using large eddy simulation and compared with direct in vivo MRI measurements. Despite the two totally different methods to obtain TKE values, both quantitative and qualitative results agreed very well. The results showed that even though both blood flow rate and Reynolds number increased after intervention, total turbulent kinetic energy levels decreased in the coarctation. Therefore, the use of the Reynolds number alone as a measure of turbulence in cardiovascular flows should be used with caution. Furthermore, the change in flow field and kinetic energy were assessed, and it was found that before intervention a jet formed in the throat of the coarctation, which impacted the arterial wall just downstream the constriction. After intervention the jet was significantly weaker and broke up almost immediately, presumably resulting in less stress on the wall. As there was a good agreement between measurements and numerical results (the increase and decrease of integrated TKE matched measurements almost perfectly while peak values differed by approximately 1 mJ), the CFD results confirmed the MRI measurements while at the same time providing high-resolution details about the flow. Thus, this preliminary study indicates that MR-based TKE measurements might be useful as a diagnostic tool when evaluating intervention outcome, while the detailed numerical results might be useful for further understanding of the flow for treatment planning.
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30.
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31.
  • Loiske, Karin, 1978- (författare)
  • Echocardiographic measurements of the heart : with focus on the right ventricle
  • 2011
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Echocardiography is a well established technique when evaluating the size and function of the heart. One of the most common ways to measure the size of the right ventricle (RV) is to measure the RV outflow tract 1(RVOT1). Several ways to measure RVOT1 are described in the literature.These ways were compared with echocardiography on 27 healthy subjects.The result showed significant differences in RVOT1, depending on the way it was measured, concluding that the same site, method and body positionshould be used when comparing RVOT1 in the same subject over time.One parameter to evaluate the RV diastolic function (RVDF) is to measure the RV isovolumetric relaxation time (RV-IVRT), a sensitive marker ofRV dysfunction. There are different ways to measure this. In this thesis two ways of measuring RV-IVRT and their time intervals were compared in 20 patients examined with echocardiography. There was a significant difference between the two methods indicating that they are not measuring the same interval.Another way to assess the RVDF is to measure the maximal early diastolicvelocity (MDV) in the long-axis direction. MDV can be measured bydifferent methods, hence 29 patients were examined and MDV was measured according to two methods. There was a good correlation but a poor agreement between the two methods meaning that reference values cannot be used interchangeably.Takotsubo cardiomyopathy is characterized by apical wall motion abnormalities without coronary stenosis. The pathology of this condition remains unclear. To evaluate biventricular changes in systolic long-axisfunction and diastolic parameters in the acute phase and after recovery, 13 patients were included and examined with echocardiography at admission and after recovery. The results showed significant biventricular improvementof systolic long-axis function while most diastolic parameters remainedunchanged.
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32.
  • Nilsson, Lennart, et al. (författare)
  • Neutrophil/Lymphocyte Ratio Is Associated with Non-Calcified Plaque Burden in Patients with Coronary Artery Disease
  • 2014
  • Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 9:9, s. e108183-
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Elevations in soluble markers of inflammation and changes in leukocyte subset distribution are frequently reported in patients with coronary artery disease (CAD). Lately, the neutrophil/lymphocyte ratio has emerged as a potenti al marker of both CAD severity and cardiovascular prognosis. Objectives: The aim of the study was to investigate whether neutrophil/lymphocyte ratio and other immune-inflammatory markers were related to plaque burden, as assessed by coronary computed tomography angiography (CCTA), in patients with CAD. Methods: Twenty patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) and 30 patients with stable angina (SA) underwent CCTA at two occasions, immediately prior to coronary angiography and after three months. Atherosclerotic plaques were classified as calcified, mixed and non-calcified. Blood samples were drawn at both occasions. Leukocyte subsets were analyzed by white blood cell differential counts and flow cytometry. Levels of C-reactive protein (CRP) and interleukin(IL)-6 were measured in plasma. Blood analyses were also performed in 37 healthy controls. Results: Plaque variables did not change over 3 months, total plaque burden being similar in NSTE-ACS and SA. However, non-calcified/total plaque ratio was higher in NSTE-ACS, 0.25(0.09-0.44) vs 0.11(0.00-0.25), pless than0.05. At admission, levels of monocytes, neutrophils, neutrophil/lymphocyte ratios, CD4+ T cells, CRP and IL-6 were significantly elevated, while levels of NK cells were reduced, in both patient groups as compared to controls. After 3 months, levels of monocytes, neutrophils, neutrophil/lymphocyte ratios and CD4+ T cells remained elevated in patients. Neutrophil/lymphocyte ratios and neutrophil counts correlated significantly with numbers of non-calcified plaques and also with non-calcified/total plaque ratio (r = 0.403, p = 0.010 and r = 0.382, p = 0.024, respectively), but not with total plaque burden. Conclusions: Among immune-inflammatory markers in NSTE-ACS and SA patients, neutrophil counts and neutrophil/lymphocyte ratios were significantly correlated with non-calcified plaques. Data suggest that these easily measured biomarkers reflect the burden of vulnerable plaques in CAD.
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33.
  • Rosendahl, Lene, et al. (författare)
  • Image quality and myocardial scar size determined with magnetic resonance imaging in patients with permanent atrial fibrillation : A comparison of two imaging protocols
  • 2010
  • Ingår i: Clinical Physiology and Functional Imaging. - : John Wiley & Sons. - 1475-0961 .- 1475-097X. ; 30:2, s. 122-129
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Magnetic resonance imaging (MRI) of the heart generally requires breath holding and a regular rhythm. Single shot 2D steady-state free precession (SS_SSFP) is a fast sequence insensitive to arrhythmia as well as breath holding. Our purpose was to determine image quality, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios and infarct size with a fast single shot and a standard segmented MRI sequence in patients with permanent atrial fibrillation and chronic myocardial infarction.Methods: Twenty patients with chronic myocardial infarction and ongoing atrial fibrillation were examined with inversion recovery SS_SSFP and segmented inversion recovery 2D fast gradient echo (IR_FGRE). Image quality was assessed in four categories: delineation of infarcted and non-infarcted myocardium, occurrence of artefacts and overall image quality. SNR and CNR were calculated. Myocardial volume (ml) and infarct size, expressed as volume (ml) and extent (%), were calculated, and the methodological error was assessed.Results: SS_SSFP had significantly better quality scores in all categories (P = 0·037, P = 0·014, P = 0·021, P = 0·03). SNRinfarct and SNRblood were significantly better for IR_FGRE than for SS_SSFP (P = 0·048, P = 0·018). No significant difference was found in SNRmyocardium and CNR. The myocardial volume was significantly larger with SS_SSFP (170·7 versus 159·2 ml, P<0·001), but no significant difference was found in infarct volume and infarct extent.Conclusion: SS_SSFP displayed significantly better image quality than IR_FGRE. The infarct size and the error in its determination were equal for both sequences, and the examination time was shorter with SS_SSFP.
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34.
  • Rosendahl, Lene, 1963- (författare)
  • Infarct size and myocardial function : A methodological study
  • 2010
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The size of a myocardial infarction (MI) and the concurrent effect on left ventricular (LV) function are essential for decisions regarding patient care and treatment. Images produced with the late gadolinium enhancement (LGE) technique visualize the scar with high spatial resolution. The general aim of this thesis was to study methods to assess scar size in chronic MI, primarily with the use of LGE, and to relate area‐at‐risk and LV function to scar size.Myocardial perfusion single photon emission computed tomography (MPS) is a well established technique for the assessment of MI size. Our study showed that there is a fairly good agreement between MPS and LGE in the determination of scar size. Wall motion score index (WMSI) correlated moderately with both infarct size and infarct extent determined with LGE.Manual delineation of myocardium and scar is time consuming and subjective and there is a need for help in objective assessment. We showed that the semi‐automatic computer software, Segment, reduced the evaluation time ≥50% with maintained clinical accuracy.The segmented scar sequence ‐ inversion recovery fast gradient echo, IR_FGRE, is a well documented sequence for scar determination, however, the sequence requires regular heart rhythm and breath holding for good imaging. We showed that a single shot scar sequence ‐ steady state free precession, SS_SSFP ‐ acquired under free breathing in patients with ongoing atrial fibrillation, had significantly better image quality than IR_FGRE. The scar size and the error of determination were equal for both sequences and the examination time was shorter with SS_SSFP.In an acute MI it is essential to know the myocardial area‐at‐risk. WMSI is clinically the most common way of assessing LV function, but is highly subjective. Tissue Doppler imaging with strain measurements is considered objective and quantitative in assessing both global and regional LV function compared to WMSI. Our results showed that WMSI is superior to strain for the detection of scar with transmurality ≥50% in patients with acute MI. Also WMSI correlated better than strain on all levels (global, regional, segmental) with final scar size determined with LGE.LGE images visualize myocardial scar much more distinctly than any other modality. This new technique needs clinical validation but promises intense competition with existing modalities such as myocardial scintigraphy and echocardiography.However, in individual patient care all modalities should be used according to their own advantages and limitation.
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35.
  • Rosendahl, Lene, 1963-, et al. (författare)
  • Longitudinal peak strain detects a smaller risk area than visual assessment of wall motion in acute myocardial infarction
  • 2010
  • Ingår i: Cardiovascular Ultrasound. - : BioMed Central (BMC). - 1476-7120. ; 8:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Background. Opening of an occluded infarct related artery reduces infarct size and improves survival in acute ST-elevation myocardial infarction (STEMI). In this study we performed tissue Doppler analysis (peak strain, displacement, mitral annular movement (MAM)) and compared with visual assessment for the study of the correlation of measurements of global, regional and segmental function with final infarct size and transmurality. In addition, myocardial risk area was determined and a prediction sought for the development of infarct transmurality 50%.Methods. Twenty six patients with STEMI submitted for primary percutaneous coronary intervention (PCI) were examined with echocardiography on the catheterization table. Four to eight weeks later repeat echocardiography was performed for reassessment of function and magnetic resonance imaging for the determination of final infarct size and transmurality.Results. On a global level, wall motion score index (WMSI), ejection fraction (EF), strain, and displacement all showed significant differences (p ≤ 0.001, p ≤ 0.001, p ≤ 0.001 and p = 0.03) between the two study visits, but MAM did not (p = 0.17). On all levels (global, regional and segmental) and both pre- and post PCI, WMSI showed a higher correlation with scar transmurality compared to strain. We found that both strain and WMSI predicted the development of scar transmurality 50%, but strain added no significant information to that obtained with WMSI in a logistic regression analysis.Conclusions. In patients with acute STEMI, WMSI, EF, strain, and displacement showed significant changes between the pre- and post PCI exam. In a ROC-analysis, strain had 64% sensitivity at 80% specificity and WMSI around 90% sensitivity at 80% specificity for the detection of scar with transmurality 50% at follow-up. 
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36.
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37.
  • Sjöblom, Peter, et al. (författare)
  • Microalbuminuria, but not reduced eGFR, is associated with cardiovascular subclinical organ damage in type 2 diabetes
  • 2014
  • Ingår i: Diabetes & Metabolism. - : Elsevier. - 1262-3636 .- 1878-1780. ; 40:1, s. 49-55
  • Tidskriftsartikel (refereegranskat)abstract
    • AIM: This study explored the association between reduced estimated glomerular filtration rate (eGFR) and microalbuminuria vs. subclinical organ damage in patients with type 2 diabetes.METHODS: Data from middle-aged patients with type 2 diabetes (n=706) treated in primary care were analyzed for microalbuminura, defined as a urinary albumin/creatinine ratio (uACR)≥3.0mmol/mol, and reduced eGFR, defined as<60mL/min/1.73m(2), in relation to blood pressure, pulse wave velocity (PWV), left ventricular mass index (LVMI), and carotid intima-media thickness (IMT) and lumen diameter (LD).RESULTS: Patients with microalbuminuria had significantly higher 24-h ambulatory systolic blood pressure (ASBP) compared with subjects with uACR<3mg/mmol: 137 vs. 128mmHg (P<0.001). There were no differences in ASBP in patients with eGFR<60mL/min/1.73m(2). However, patients with vs. without microalbuminuria had increased PWV (11.4 vs. 10.1m/s; P<0.001), LVMI (134.4 vs. 118.6g/m(2); P<0.001), LD (7.01±0.93 vs. 6.46±0.74mm; P<0.001) and IMT (0.78 vs. 0.74mm; P=0.047), respectively. The associations between uACR vs. PWV and LVMI were more robust after adjusting for age, diabetes duration, ASBP, HbA1c, LDL-cholesterol, and antihypertensive and lipid-lowering therapy compared with uACR vs. IMT. There were no statistically significant differences in PWV, LVMI or IMT between patients with reduced (<60mL/min/1.73m(2)) vs. normal eGFR.CONCLUSION: Levels of urinary albumin excretion, but not reduced eGFR, were associated with increased arterial stiffness, left ventricular mass and atherosclerosis in patients with type 2 diabetes.
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38.
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39.
  • Spångeus, Anna, et al. (författare)
  • Toe brachial index in middle aged patients with diabetes mellitus type 2 : Not just a peripheral issue
  • 2013
  • Ingår i: Diabetes Research and Clinical Practice. - : Elsevier. - 0168-8227 .- 1872-8227. ; 100:2, s. 195-202
  • Tidskriftsartikel (refereegranskat)abstract
    • AimTo explore risk factors for peripheral arterial disease (PAD) as well as the association between toe blood pressure and subclinical and clinical central vascular disease in patients with type 2 diabetes.MethodToe brachial index (TBI) was cross-sectionally analyzed in 742 middle-aged (54–66 years) patients with type 2 diabetes as well as non-diabetic controls and related to other vascular measures (e.g. carotid intima media thickness (IMT), presence of carotid plaque, central arterial stiffness and left ventricular mass index) and previous cardiovascular events.ResultsA TBI ≤ 0.7 was seen in 22% of the patients but only one patient had severe TBI reduction (TBI ≤ 0.3). The corresponding figures in the controls were 13% and 0%, respectively. Mean TBI was significantly lower in patients with type 2 diabetes than in controls (0.81 ± 0.14 vs. 0.87 ± 0.15, p < 0.001). In patients with diabetes, a lower TBI was associated with increased central arterial stiffness (p < 0.001), IMT (p < 0.001) and carotid plaque (p < 0.001) as well as with decreasing glomerular filtration rate (p < 0.001). Lower TBI was found in patients with previous macrovascular ischemic events. Furthermore, TBI was negatively correlated with age (p < 0.001), diabetes duration (p < 0.001) and HbA1c (p = 0.01).ConclusionPAD, assessed with TBI, is common in a Swedish middle-aged diabetes type 2 cohort, affecting about one-fifth. As ankle pressure may be confounded by falsely high values in patients with diabetes due to media calcification we conclude that information about TBI may improve the risk evaluation regarding arteriosclerotic disease in both small and large vessels in type 2 diabetes.
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40.
  • Tengblad, Anders, et al. (författare)
  • Sagittal abdominal diameter and waist circumference as markers of early organ damage in patients with Type 2 diabetes
  • 2011
  • Ingår i: Journal of Clinical Metabolism & Diabetes. - : San Lucas Medical. ; 2:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Aims: In a cohort of 465 patients with Type 2 diabetes aged 55-66 years the associationbetween the anthropometric measures: Waist circumference (WC) and Sagittal abdominaldiameter (SAD) versus subclinical cardiovascular organ damage by measuring Pulse wavevelocity (PWV) and Left ventricular mass index (LVMI) was studied.Methods: Blood pressure, weight, height and WC were measured within primary care. SADwas measured by using standardized calliper equipment. Blood samples were taken foranalysis of HbA1c and serum lipids. LVMI was measured by M-mode echocardiography.Aortic PWV was measured by applanation tonometry (Sphygmocor®) over the carotid andfemoral arteries.Results: There were significant correlations between aortic PWV and WC (r=0.23; p<0.01)and SAD (r=0.25; p<0.01). LVMI was also correlated to WC (r=0.26; p<0.01) and SAD(r=0.25; p<0.01). When analysed in a multiple regression model, SAD and WC were bothassociated with PWV and LVMI, independently of age, sex, systolic blood pressure, serumlipids and HbA1c.Conclusion: This study shows that abdominal obesity, measured either with WC or SAD, is afeasible risk assessment tool for early subclinical organ damage in patients who have alreadydeveloped Type 2 diabetes.
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41.
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42.
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43.
  • Tödt, Tim, et al. (författare)
  • Relationship between treatment delay and final infarct size in STEMI patients treated with abciximab and primary PCI
  • 2012
  • Ingår i: BMC Cardiovascular Disorders. - : Springer Science and Business Media LLC. - 1471-2261 .- 1471-2261. ; 12:9, s. 1-9
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundStudies on the impact of time to treatment on myocardial infarct size have yielded   conflicting results. In this study of ST-Elevation Myocardial Infarction (STEMI) treated   with primary percutaneous coronary intervention (PCI), we set out to investigate the   relationship between the time from First Medical Contact (FMC) to the demonstration   of an open infarct related artery (IRA) and final scar size.Between February 2006 and September 2007, 89 STEMI patients treated with primary PCI   were studied with contrast enhanced magnetic resonance imaging (ceMRI) 4 to 8 weeks   after the infarction. Spearman correlation was computed for health care delay time   (defined as time from FMC to PCI) and myocardial injury. Multiple linear regression   was used to determine covariates independently associated with infarct size.ResultsAn occluded artery (Thrombolysis In Myocardial Infarction, TIMI flow 0-1 at initial   angiogram) was seen in 56 patients (63%). The median FMC-to-patent artery was 89 minutes.   There was a weak correlation between time from FMC-to-patent IRA and infarct size,   r = 0.27, p = 0.01. In multiple regression analyses, LAD as the IRA, smoking and an occluded vessel   at the first angiogram, but not delay time, correlated with infarct size.ConclusionsIn patients with STEMI treated with primary PCI we found a weak correlation between   health care delay time and infarct size. Other factors like anterior infarction, a   patent artery pre-PCI and effects of reperfusion injury may have had greater influence   on infarct size than time-to-treatment per se.
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44.
  • Tödt, Tim, 1964- (författare)
  • Strategies to improve outcome in patients with ST elevation myocardial infarction treated with primary PCI
  • 2012
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Background: ST elevation myocardial infarction (STEMI) caused by a ruptured atherosclerotic plaque with overlying thrombosis leads to ischemia and progressively to the death of the myocardial cells supplied by the affected coronary artery. Rapid reperfusion with primary Percutaneous Coronary Intervention (PCI) in an experienced centre is the preferred therapy for these patients. The aim of the research program on which this thesis is based was to study the effect of antiplatelet therapy with abciximab on coronary patency  when administered early to an unselected cohort of patients with STEMI intended for primary PCI, to study the impact of health care delay time on infarct size measured with contrast enhanced Magnetic Resonance Imaging (ceMRI), and to evaluate if time delays could be reduced through reorganisation of logistics and personal feedback to staff involved in the care of STEMI patients. Finally measures of wall motion on cine MRI were evaluated to elucidate if functional measurements of the left ventricular wall could detect scar tissue visualised on ceMRI in a post-acute phase of primary PCI.Material and results: In paper I we report on a study of all consecutive patients who sustained a STEMI in 2005 in the county of Östergötland and who were to be treated with primary PCI. Abciximab given as pretreatment before (n=133) or at the cath-lab after a diagnostic angiography (n=109) was associated with a patent Infarct Related Artery (IRA), i.e. Thrombolysis in Myocardial Infarction (TIMI) flow 2-3, in 45.9% of patients in the early group versus 20.2% in the cath-lab group, p=0.0001. There were no statistically significant differences in bleeding or mortality rate during the initial hospital stay, nor were there any significant differences between the groups during one-year follow up regarding a Major Adverse Cardiac Event (MACE).Paper II is based on an examination of 30 patients in a stable clinical condition with ceMRI 4-8 weeks after they had been treated with primary PCI because of STEMI. Patients were selected on the presence of extensive myocardial scar in the anteroseptal segments (n=17) or no scar visible at all in this area or in any other part of the myocardium (n=13). The purpose of the study was to evaluate the ability of a new feature tracking software to measure functional parameters of the heart. The left ventricular wall was divided into 18 segments and myocardial contraction was measured with velocity, displacement and strain in the longitudinal and radial direction. The software calculated a mean value for the 18 segments for each parameter. Receiver-operatorcharacteristics curves (ROC) were constructed. The best area-under-curve (AUC) was for radial strain where a cut-off value of 38.8% had 80% sensitivity and 86% specificity to detect segments with scar>50%.The impact of health care delay was examined in paper III based on a study in which 89 STEMI patients treated with primary PCI had their infarct size measured with ceMRI in the post-acute phase. Time from First Medical Contact (FMC) to a patent artery correlated weakly with infarct size, r=0.27, p=0.01. However, multivariable analysis showed the LAD as the Infarct Related Artery (IRA), active smoking and occlusion of the IRA at the time of the diagnostic angiogram were correlated with infarct size and that time from FMC to patent artery was not so correlated.Finally, in the study leading to paper IV, extensive measurements on time delays were performed on 67 consecutive patients with STEMI treated with primary PCI. Through collaboration with different stakeholders in the treatment of STEMI in the catchment area the following types of targeted refining of logistics were done; 1. Ambulance staff prioritise ECG recording, 2. Central evaluation of ECG in all patients with suspected STEMI, and 3. PCI team is ready to accept the patient when two out of three members are on site. Moreover, personal feedback on time delays for each STEMI patient was given to all staff involved in the treatment of the patient. Thereafter, all the time delays for a similar group of consecutive STEMI patients (n=89) were analysed and compared with the delays for the former group. Improvements seen in the post-intervention group were a reduction in time from ECG to cath-lab arrival by 11 minutes, p=0.02 and a non-significant decrease of FMC to a patent artery by six minutes. The main part of this improvement could probably be ascribed to the decision to see to it that an attending cardiologist was present 24/7 and to central evaluation of ECG.Conclusion: Abciximab given as pre-treatment to patients with STEMI intended for primary PCI was associated with a patent artery in 46% of patients. Moreover, we demonstrated a relationship between health care delay time and infarct size. This delay time could be reduced by a reorganisation of logistics and personal feedback on time delays. Finally, feature tracking analysis of cine MR images could detect segments with extensive myocardial scar in anterior infarction with 80% sensitivity and 86% specificity.
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45.
  • Waldreus, Nana, et al. (författare)
  • Thirst response to acute hypovolaemia in healthy women and women prone to vasovagal syncope
  • 2013
  • Ingår i: Physiology and Behavior. - : Elsevier. - 0031-9384 .- 1873-507X. ; 120, s. 34-39
  • Tidskriftsartikel (refereegranskat)abstract
    • The present study measured self-perceived thirst and plasma angiotensin II (ATII) concentrations during graded hypovolaemic stress, induced by lower body negative pressure (LBNP), to elucidate the dependence of thirst on haemodynamics. A total of 24 women aged between 20 and 36 (mean age, 23) years rated their thirst on a visual analogue scale, graded from 0 to 100, when LBNP of 20,30 and 40 mm Hg was applied. Half of the women had a history of vasovagal syncope (VVS). The results showed that the thirst score increased three-fold when LBNP was applied, from 11 (median; 25th-75th percentiles, 9-25) to 34 (27-53; P andlt; 0.001). The women in the VVS group had twice as great an increase as those without a history of VVS (P andlt; 0.02). The plasma ATII concentration increased significantly in response to LBNP, both in the VVS group and in the control group, but the changes did not correlate with thirst. Application of LBNP decreased systolic and mean arterial pressures, cardiac output and pulse pressure (P andlt; 0.001 for all), but thirst correlated only with increase in heart rate and, independently, with reduction of mean arterial pressure. In conclusion, thirst and ATII increase in response to hypovolaemic stress, but are not statistically related. The haemodynamic parameter that was most strongly related to thirst was tachycardia.
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46.
  • Wang, Chunliang, 1980-, et al. (författare)
  • Can segmented 3D images be used for stenosis evaluation in coronary CT angiography?
  • 2012
  • Ingår i: Acta Radiologica. - : Sage Publications. - 0284-1851 .- 1600-0455. ; 53:8, s. 845-851
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Thanks to the development of computed tomography (CT) scanners and computer software, accurate coronary artery segmentation can be achieved with minimum user interaction. However, the question remains whether we can use these segmented images for reliable diagnosis. Purpose: To retrospectively evaluate the diagnostic accuracy of coronary CT angiography (CCTA) using segmented 3D data for the detection of significant stenosis. Material and Methods: CCTA data-sets from 30 patients were acquired with a 64-slice CT scanner and segmented using the region growing (RG) method and the "virtual contrast injection" (VC) method. Three types of images of each patient were reviewed by different reviewers for the presence of stenosis with diameter reduction of 50% or more. The evaluation was performed on four main arteries of each patient (120 arteries in total). For the original series, the reviewer was allowed to use all the 2D and 3D visualization tools available (conventional method). For the segmented results from RG and VC, only maximum intensity projection was used. Evaluation results were compared with catheter angiography (CA) for each artery in a blinded fashion. Results: Overall, 34 arteries with significant stenosis were identified by CA. The percentage of evaluable arteries, accuracy and negative predictive value for detecting stenosis were, respectively, 86%, 74%, and 93% for the conventional method, 83%, 71%, and 92% for VC, and 64%, 56%, and 93% for RG. Accuracy was significantly lower for the RG method than for the other two methods (P < 0.01), whereas there was no significant difference in accuracy between the VC method and the conventional method (P = 0.22). Conclusion: The diagnostic accuracy for the RG-segmented 3D data is lower than those with access to 2D images, whereas the VC method shows diagnostic accuracy similar to the conventional method.
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47.
  • Warntjes, Marcel JB, 1964-, et al. (författare)
  • Rapid T1 quantification based on 3D phase sensitive inversion recovery
  • 2010
  • Ingår i: BMC Medical Imaging. - : Springer Science and Business Media LLC. - 1471-2342. ; 10:19
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: In Contrast Enhanced Magnetic Resonance Imaging fibrotic myocardium can be distinguished from healthy tissue using the difference in the longitudinal T1 relaxation after administration of Gadolinium, the so-called Late Gd Enhancement. The purpose of this work was to measure the myocardial absolute T1 post-Gd from a single breath-hold 3D Phase Sensitivity Inversion Recovery sequence (PSIR). Equations were derived to take the acquisition and saturation effects on the magnetization into account.METHODS: The accuracy of the method was investigated on phantoms and using simulations. The method was applied to a group of patients with suspected myocardial infarction where the absolute difference in relaxation of healthy and fibrotic myocardium was measured at about 15 minutes post-contrast. The evolution of the absolute R1 relaxation rate (1/T1) over time after contrast injection was followed for one patient and compared to T1 mapping using Look-Locker. Based on the T1 maps synthetic LGE images were reconstructed and compared to the conventional LGE images.RESULTS: The fitting algorithm is robust against variation in acquisition flip angle, the inversion delay time and cardiac arrhythmia. The observed relaxation rate of the myocardium is 1.2 s-1, increasing to 6 - 7 s-1 after contrast injection and decreasing to 2 - 2.5 s-1 for healthy myocardium and to 3.5 - 4 s-1 for fibrotic myocardium. Synthesized images based on the T1 maps correspond very well to actual LGE images.CONCLUSIONS: The method provides a robust quantification of post-Gd T1 relaxation for a complete cardiac volume within a single breath-hold.
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48.
  • Wijkman, Magnus, et al. (författare)
  • Ambulatory systolic blood pressure predicts left ventricular mass in type 2 diabetes, independently of central systolic blood pressure
  • 2012
  • Ingår i: Blood Pressure Monitoring. - : Lippincott Williams & Wilkins. - 1359-5237 .- 1473-5725. ; 17:4, s. 139-144
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives: Both ambulatory and central blood pressures have been reported to correlate more closely than office blood pressure with left ventricular mass index (LVMI). The aim of this study was to test whether ambulatory systolic blood pressure (SBP) predicts LVMI independently of central SBP in patients with type 2 diabetes.Methods: We determined office, ambulatory and central blood pressures and performed echocardiography in 460 patients with type 2 diabetes, who participated in the CARDIPP (Cardiovascular Risk factors in Patients with Diabetes – a Prospective study in Primary care) study (ClinicalTrials.gov number NCT 01049737).Results: In separate multivariable regression models, both 24-hour ambulatory SBP, ambulatory day-time SBP, and ambulatory night-time SBP were significantly associated with LVMI, independently of central SBP, age, sex, BMI, ambulatory 24-hour heart rate, duration of known diabetes and presence or absence of any antihypertensive medications (r = 0.19, 0.17 and 0.18, respectively, P <0.01). All ambulatory SBP parameters, but not central SBP, were significantly associated with LVMI independently of office SBP.Conclusions: Ambulatory SBP predicted LVMI independently of central SBP in patients with type 2 diabetes. The use of ambulatory blood pressure measurements may be encouraged as a tool for refined risk stratification of patients with type 2 diabetes.
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49.
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50.
  • Wijkman, Magnus, et al. (författare)
  • ß-blocker Treatment is Associated with High Augmentation Index and with High Aortic, but not Brachial, Pulse Pressure in Type 2 Diabetes
  • 2010
  • Ingår i: The journal of clinical metabolism and diabetes. ; 1:1, s. 55-62
  • Tidskriftsartikel (refereegranskat)abstract
    • Aims: To explore the associations between ß-blocker treatment and clinic, ambulatory, and central pulse pressure (PP) and central augmentation index (AIx), and left ventricular mass index (LVMI), respectively, in patients with type 2 diabetes.Methods: In 124 middle-aged patients with type 2 diabetes who were treated in primary care and used at least one antihypertensive drug, we measured clinic PP (mean value of three nurse-recorded measurements in the sitting position) and ambulatory PP (24-hour ambulatory measurements with the Spacelab 90217 measurement device). Central PP was measured non-invasively, using applanation tonometry (SphygmoCor), which also yielded values of AIx. LVMI was determined echocardiographically in all patients.Results: Patients whose antihypertensive drug regimen included a ß-blocker (n=67) had significantly higher central PP compared with patients whose antihypertensive drug regimen did not include a ß-blocker (ß-blocker: 49.6±12.2 mmHg, no ß-blocker: 45.1±10.2 mmHg; p=0.03) despite having similar clinic PP (ß-blocker: 60.4±16.3 mmHg, no ß-blocker: 58.9±13.1 mmHg; p=0.59) and similar ambulatory PP (ß-blocker: 55.2±9.1 mmHg, no ß-blocker: 54.8±10.6 mmHg; p=0.40). Patients treated with ß-blockers also had significantly higher AIx (ß-blocker: 30.7±8.4%, no ß-blocker: 25.8±8.8%; p<0.01) and higher LVMI (ß-blocker: 129.5±29.7 g/m2, no ß-blocker: 117.4±27.4 g/m2; p=0.02) compared with patients who were not treated with ß-blockers.Conclusions: In our cohort, ß-blocker use was associated with high central but not brachial PP and with high central AIx and high LVMI. Non-invasive measurement of central hemodynamic parameters may improve the evaluation of antihypertensive treatment efficacy in patients with type 2 diabetes.
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