Regional contractile dysfunction is a frequent finding in hypertrophic cardiomyopathy ( HCM) and fenocopies. Previous studies predominantly performed with echocardiography speckle tracking have shown that there is widespread variation in myocardial contractility throughout the ventricle in left ventricular hypertrophy related to the extent of hypertrophy and presence of replacement fibrosis. Alternative method to echocardiography for the assessment of regional strain is cardiovascular magnetic resonance (CMR) post processing feature tracking (FT).
We aimed to investigate the contribution of different tissue characteristics in left ventricular hypertrophy to regional contractile dysfunction.
We prospectively recruited 60 patients with left ventricular hypertrophy who underwent CMR studies at 1.5 T including cine imaging and late gadolinium enhancement (LGE) imaging. For each segment of the American Heart Association model segment thickness, presence of LGE and regional strain (by FT) were assessed. The relationship of segmental function, hypertrophy and tissue characteristics were determined using a mixed effects model, with random intercept for each patient.
Univariate analysis showed statistically significant association of individually segment thickness and the presence of LGE with regional strain parameters.
The multivariable model ( segment thickness and LGE) demonstrated that all strain parameters were associated with both segment thickness (P < 0.05 for all) and LGE (p < 0.05 for all). Table 1.
Impairment of contractile function in left ventricular hypertrophy is associated with the degree of hypertrophy and extracellular fibrosis ( LGE).