Increased left ventricular torsion in hypertrophic cardiomyopathy mutation carriers with normal wall thickness
© Rüssel et al; licensee BioMed Central Ltd. 2009
Published: 28 January 2009
To determine the amount of left ventricular (LV) torsion in hypertrophic cardiomyopathy (HCM) mutation carriers (carriers) with normal wall thickness.
Ten carriers with an LV wall thickness <10 mm, and ten age and gender matched controls underwent CMR cine imaging and tissue tagging. LV volumes were calculated from the cine images. Basal and apical rotations and LV torsion, defined as the circumferential-longitudinal shear angle , were determined from tissue tagging. Counterclockwise rotation as seen from the apex was considered positive. LV volumes, peak rotation and torsion were compared between both groups using Student's T-test. A p-value < 0.05 was considered significant.
LV end-diastolic and end-systolic volumes were not significantly different between both groups (p = 0.79 and p = 0.36, resp.), whereas EF was significantly larger in the carriers (63.2 ± 3.2% vs. 59.7 ± 2.8%, p = 0.02). Peak apical rotation and peak torsion were significantly larger in the carriers (14.6 ± 3.2° vs. 10.3 ± 3.3°, p = 0.01, and 10.2 ± 2.3° vs. 7.1 ± 1.0°, p = 0.001, resp.), while peak basal rotation was significantly smaller (-2.5 ± 2.2° vs. -4.6 ± 1.7°, p = 0.03).
HCM mutation carriers with normal wall thickness demonstrate increased LV torsion. Underlying altered myocardial architecture might be responsible for this finding.
This article is published under license to BioMed Central Ltd.