SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Emilsson Kent) srt2:(2015-2016)"

Sökning: WFRF:(Emilsson Kent) > (2015-2016)

  • Resultat 1-5 av 5
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Jorstig, Stina, 1978-, et al. (författare)
  • Distance and area measurement of the right atrium and ventricle by echocardiography and cardiac magnetic resonance imaging : do we measure the same thing?
  • 2016
  • Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
    • Purpose: It has previously been shown that stroke volumes measured by transthoracic echocardiography (TTE) are underestimated, compared to cardiac magnetic resonance (CMR) imaging. The purpose of this study was to evaluate differences in distance and area measurements of the right atrium (RA) and the right ventricle (RV) by TTE and CMR.Methods: TTE examinations and CMR examinations were subsequently performed in 12 healthy volunteers. Three distances (RAL - right atrial length, RVIT3 - right ventricular inflow tract, RVLAX - right ventricular long axis) and one area (RVA - right ventricular area) were measured in TTE and CMR. Stroke volumes were also calculated using conventional methods available on each modality. Both intramodality and intermodality comparisons were performed based on measurements from three observers. One of the observers performed measurements in both TTE and CMR.Results: Intermodality comparisons showed that all distance and area measurements were significantly smaller using TTE (Table 1). Two of the measurements, RVIT3 and RVA, differed at about 50%. Calculated stroke volumes showed, consistent with previous results, that the TTE stroke volumes are substantially underestimated compared to CMR volumes. Intramodality variations of distance and area measurements were considerably smaller (Table 1).Conclusions: Our results show that RV distances and areas measured by TTE are smaller compared to CMR, probably due to differences in defining the endocardial borders. These differences subsequently result in smaller stroke volumes when using TTE. Caution should be taken when comparing distances, areas and volumes measured by TTE and CMR.
  •  
2.
  • Jorstig, Stina Hellstrand, 1978-, et al. (författare)
  • A study to determine the contribution to right ventricle stroke volume from pulmonary and tricuspid valve displacement volumes
  • 2015
  • Ingår i: Clinical Physiology and Functional Imaging. - : Wiley-Blackwell. - 1475-0961 .- 1475-097X. ; 35:4, s. 283-290
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Describing the systolic function of the right ventricle (RV) is a difficult task due to the complex shape and orientation of the RV. The purpose of this study was to investigate the extent to which the volumes encompassed by the pulmonary and tricuspid valve displacements contribute to the total right ventricle stroke volume (RVSV).METHODS: Twelve healthy volunteers were examined using cardiac magnetic resonance (CMR). Two series of time-resolved axially rotated MR images were acquired that encompassed the tricuspid valve and the pulmonary valve, respectively. The volume related to each valve movement, the tricuspid plane displacement (TPD) and the pulmonary plane displacement (PPD), was determined by delineation in diastole and systole. These volumes, RVSVTPD and RVSVPPD , were compared to the stroke volume to determine the contributions to the total stroke volume from the TPD and the PPD. The remaining volume of the total RVSV was referred to as RVSVOther . An initial in vitro study was carried out to validate the accuracy of volume measurements using axially rotated images.RESULTS: In vitro measurements indicated that the method for volumetric measurements using axially rotated images was a very accurate one, with a mean difference of 0·04 ± 0·10 ml. The in vivo measurements of RVSVTPD , RVSVPPD and RVSVOther were 45 ± 10%, 13 ± 2% and 42 ± 11%, respectively.CONCLUSIONS: Right ventricle stroke volume is determined by different individual volume changes as follows: RVSVTPD together with RVSVOther contributes to almost the entire RVSV in nearly equal proportions, while RVSVPPD contributes only a small amount and is approximately 30% of either RVSVTPD or RVSVOther.
  •  
3.
  • Jorstig, Stina, 1978- (författare)
  • On the assessment of right ventricular function using cardiac magnetic resonance imaging and echocardiography
  • 2016
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) imaging are two commonly used imaging modalities for evaluating the size and function of the heart. There are advantages and disadvantages associated with both modalities when examining the right ventricle (RV).The RV is positioned partly behind the sternum and lung, sometimes causing shadows in the TTE images. This along with the complex shape of the RV makes volume calculations challenging by 2D TTE. CMR is considered to be the reference method for volume calculations of the ventricles. The valve separating the RV from the right atrium is however often oblique compared to the valve separating the left ventricle from the left atrium. This complicates RV volume calculations using conventional CMR short-axis stack images. The aim of this thesis was to find ways to improve the RV stroke volume and ejection fraction calculations using TTE and CMR.A method, transferring the position of the tricuspid plane from RV long-axis images to short-axis images, was developed to improve the separation of the right atrium from the RV when calculating RV stroke volumes by CMR. The method provided calculations of RV stroke volumes with good agreement to reference volumes. Further, the movements contributing to the RV stroke volume was studied aiming to find new ways of calculating RV stroke volumes and ejection fraction by TTE. A model for RV stroke volume and ejection fraction calculations was evaluated showing underestimation of stroke volumes by TTE compared to CMR, which probably depend on differences in distance measurements using the two modalities. The model provided, however, promising results for ejection fraction calculations which was validated in a study of 37 participants that covered a wide range of EF.
  •  
4.
  • Kumar, Sanjay, et al. (författare)
  • Diastolic function improves after resolution of takotsubo cardiomyopathy
  • 2016
  • Ingår i: Clinical Physiology and Functional Imaging. - : Wiley-Blackwell. - 1475-0961 .- 1475-097X. ; 6:1, s. 17-24
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Takotsubo cardiomyopathy (TTC) is a condition of reversible left ventricular (LV) systolic dysfunction. However, the diastolic function (DF) manifestations of TTC have not been widely investigated. We performed a bicentric study with retrospective analysis of DF in patients with TTC, during onset and at follow-up.METHODS: Twenty-eight patients with TTC (64 ± 10 years, F 24) were included. All underwent echocardiograms acutely and at the recovery phase (average three months later). Diastolic and systolic function parameters were recorded, including E-wave velocity (E), A-wave velocity, E/A ratio, relaxation (e') and contractility (S') based on tissue Doppler velocities of the mitral annuli, ejection fraction (EF), left atrial (LA) size and DF stages.RESULTS: Recovery, including the mean difference with 95% confidence interval, was associated with tending improvement (i.e. uncorrected significance) in E [13 cm s(-1) (-24, -2·3), P = 0·02] and in E/A ratio [0·2 (-0·41, -0·02), P = 0·04], as well as significant improvement (after multiple comparison correction) in mean e' [2·0 cm s(-1) (-3·3, -1·2), P<0·001] and in A-wave duration [29 ms (-46·7, -12·7), P = 0·002]. LA area tended to decrease during recovery [-2 cm² (0·33, 2·4), P = 0·01]. Improvement in DF stages was significant between the phases (21% versus 58% defined as normal DF, P = 0·016). Improvement in LVEF correlated with improvement in mean e' (r = 0·52, P = 0·02).CONCLUSIONS: TTC is associated with an acute impairment of conventional DF variables, which improves during recovery. DF recovery seems to occur in parallel with systolic recovery in patients with TTC.
  •  
5.
  • Waldenborg, Micael, 1981-, et al. (författare)
  • Effect on left ventricular mass and geometry in patients with takotsubo cardiomyopathy
  • 2015
  • Ingår i: Scandinavian Cardiovascular Journal. - : Informa UK Limited. - 1401-7431 .- 1651-2006. ; 49:1, s. 27-38
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives: Takotsubo cardiomyopathy (TTC) is a condition of transient left ventricular (LV) dysfunction. The effects on LV mass (LVM) and geometry have not been studied enough in TTC. Retrospectively, we analyzed our TTC cohort both by transthoracic echocardiography (TTE) and magnetic resonance imaging (MRI), for comparative purposes.Design: Thirteen women undergoing TTE and MRI, at onset and three months later, were included. LVM was estimated by MRI, and two TTE-methods. Segmental wall thickness (SWT) was measured, whilst radial strain was assessed by TTE. Data analysis included Wilcoxon's test (between phases), Mann Whitney U- and McNemar's tests (between and within groups). Bland-Altman analyzes were used for intertechnique coherence, whilst interactions regarding TTE were tested using Spearman's coefficient.Results: LVM decreased during recovery (p<0.05), by MRI and one of the TTE-methods; truncated ellipsoid formula (TEF), which also showed relatively better coherence compared to MRI. SWT decreased in two of three sites, by both modalities, but with ambiguous coherence therebetween. The TEF-data interacted partially with a demonstrated increase in radial strain.Conclusions: TTC associates with acute increase in LVM, which appears to be an apical effect, tending to follow the changes in concentric wall motion. MRI and TTE show adequate coherence; primarily for the TEF-method regarding LVM.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-5 av 5

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy