Hypertrophic cardiomyopathy with mild left ventricular remodeling: echocardiographic assessment using left ventricular wall motion score

OBJECTIVES: The present study sought to investigate the echocardiographic features of hypertrophic cardiomyopathy (HCM) with mild left ventricular (LV) remodeling, particularly in relation to wall motion abnormalities. METHODS: Among the 137 consecutive patients with HCM, 13 patients (mean age 52 +/- 13 years) who progressed to mild LV systolic dysfunction (LV ejection fraction (LVEF) of 35-50%) were studied. By reviewing the echocardiograms of these patients, wall motion score index (WMSI) was scored using 16 segments model. RESULTS: HCM patients with mild LV systolic dysfunction exhibited mild LV dilatation, mild left atrial dilatation, septal hypertrophy, and LV wall motion impairment localized in the septal and apical regions (septal WMSI 1.94 +/- 0.33 vs. total WMSI 1.51 +/- 0.25 and posterior WMSI 1.02 +/- 0.07; p < 0.001). During follow-up, further deterioration of LV systolic function (LVEF< 35%) was noted in five patients, who had less severe hypertrophy at the initial echocardiograms. These patients developed progressive LV cavity enlargement and more severe and extensive wall motion abnormalities, accompanied by septal akinesis and wall thinning, although posterolateral wall motion impairment was relatively mild (posterior WMSI 1.80 +/- 0.27 vs. septal WMSI 2.95 +/- 0.11; p < 0.001). CONCLUSIONS: Septal and apical wall motions are reduced in HCM with mild LV remodeling. As LV dysfunction progresses, septal akinesis and wall thinning develop and LV cavity enlargement becomes more prominent, though posterolateral wall motion impairment is relatively mild.