| 1. |
- 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.
|
|
| 2. |
- 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.
|
|
| 3. |
- Åström Aneq, Meriam
(författare)
-
Arrhythmogenic right ventricular cardiomyopathy : Is it right?
- 2011
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart disease, where sudden cardiac death in young seemingly healthy persons may be the first symptom. There is a need for more sensitive and accurate diagnostic methods to detect signs of disease, at an early stage and in relatives of affected individuals. The aim of this thesis is the evaluation of new non-invasive modalities in assessment of right ventricular (RV) volume and function with focus on patients with ARVC.Clinical and non-invasive follow-up of fifteen patients with ARVC during a mean period of 8 years permitted the evaluation of disease progression. RV volume analysis by magnetic resonance imaging relies on short axis (SA) views. A new axially rotated modality acquisition was tested and its feasibility in assessment of RV volume was evaluated. This acquisition seems to be able to improve the assessment of RV volume and function by reducing the uncertainty in defining the basal slice of the RV. A third study concentrated on analysis of RV regional and general function by echocardiography, using tissue Doppler imaging as well as two dimensional (2D) longitudinal strain based on speckle tracking in patients with ARVC, their first degree relatives and in healthy subjects. 2D strain showed a good feasibility in analysis of the RV function in relatives and controls but less in ARVC patients probably due to the progressive myocardial cell death with fibro-fatty replacement of the RV wall. In order to detect and follow up echocardiographic changes an index was developed combining dimensional and functional parameters for the left and for the right ventricle. Advances in the molecular genetics of ARVC have provided new insights into the understanding of the disease. Hitherto, 9 candidate genes have been identified. A new mutation in the plakophilin 2 gene was detected in a three generation family. The clinical phenotype related to this mutation was investigated.The studies have evaluated and developed methods for studying the right ventricle with special emphasis on ARVC. With the ultimate goal of preventing sudden death in ARVC, a combination of genetic testing and improved diagnostic methods may create an improved algorithm for risk stratification and selection to prophylactic treatment.
|
|
| 4. |
- Åström Aneq, Meriam, 1964-
(författare)
-
Right Ventricular Longitudinal Strain based on Magnetic Resonance Feature Tracking in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy
- 2014
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Introduction:Arrhythmogenic right ventricular cardiomyopathy (ARVC) causes fibro-fatty substitution of the myocardium in the right ventricle (RV). Cardiovascular magnetic resonance imaging (CMR) is the gold standard for visualization and volume quantification of the RV, but the assessment of wall motion, is still based on qualitative “eye-balling”. Previous studies have shown the successful application of feature tracking (CMR-FT) to the left ventricle. The aim of this study was to test the feasibility of CMR-FT to assess RV strain in patients (P) with ARVC and in healthy controls(C).Methods: Thirteen patients fulfilling Task Force Criteria for ARVC and twenty healthy subjects underwent cardiac MRI at 1,5 Tesla. Steady-state free precession cine of six long axis slices was acquired by rotating the cut planes around the long axis of the RV. The 3-, 4- and 2-chamber views of the RV were identified. Segmental longitudinal strain was measured and re-calculated in terms of regional strain for the base (B), mid (M) and apical (A) levels of the RV and for the anterior, inferior, septal and free walls. Results: RV end systolic volume was significantly higher and ejection fraction lower in patients (104-82 ml, 49- 56%). Longitudinal strain decreased from base to apex in both groups (P:-25%, -22%, -19%, C:-31%, -24%, -20%). In a wall based analysis, the absolute strain values were significantly lower in patient lateral (P-24%, C -32%) and anterior walls (P -22%, C-28 %) but not in inferior (P-26%, C -27%) and septal walls (P -15%, C -18%). Conclusion: Feature tracking was successfully applied to the RV in this cohort of ARVC patients. Longitudinal absolute strain was lower in the basal segments, the anterior and the free walls compared to controls. This supports previous reports on the uneven regional distribution of ARVC.
|
|
| 5. |
- Åström, Meriam Aneq, et al.
(författare)
-
Evaluation of right and left ventricular function using speckle tracking echocardiography in patients with arrhythmogenic right ventricular cardiomyopathy and their first degree relatives
- 2012
-
Ingår i: Cardiovascular Ultrasound. - : BioMed Central. - 1476-7120. ; 10:37
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction and aim: The identification of right ventricular abnormalities in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) in early stages is still difficult. The aim of this study was to investigate if longitudinal strain based on speckle tracking can detect subtle right (RV) or left ventricular (LV) dysfunction as an early sign of ARVC. Methods and results: Seventeen male patients, fulfilling Task force criteria for ARVC, 49 (32-70) years old, nineteen male first degree relatives 29 (19-73) y.o. and twenty-two healthy male volunteers 36 (24-66) y.o participated in the study. Twelve-lead and signal-averaged electrocardiograms were recorded. All subjects underwent echocardiography. LV and RV diameters, peak systolic velocity from tissue Doppler and longitudinal strain based on speckle tracking were measured from the basal and mid segments in both ventricles. RV longitudinal strain measurement was successful in first degree relatives and controls (95 resp. 86%) but less feasible in patients (59%). Results were not systematically different between first degree relatives and controls. Using discriminant analysis, we then developed an index based on echocardiographic parameters. All normal controls had an index less thanl while patients with abnormal ventricles had an index between 1-4. Some of the first degree relatives deviated from the normal pattern. Conclusion: Longitudinal strain of LV and RV segments was significantly lower in patients than in relatives and controls. An index was developed incorporating dimensional and functional echocardiographic parameters. In combination with genetic testing this index might help to detect early phenotype expression in mutation carriers.
|
|
