PROGRESSION OF LEFT-VENTRICULAR ENLARGEMENT IN PATIENTS WITH HYPERTROPHIC CARDIOMYOPATHY - INCIDENCE AND PROGNOSTIC VALUE

A total of 51 patients with hypertrophic cardiomyopathy (HCM) were fol lowed for at least 3 years (mean follow-up period 6.5 years) by serial M-mode and two-dimensional echocardiography. An increase of the left ventricular diastolic dimension (LVDd) to greater-than-or-equal-to 55 mm with a decrease in the left ventricular ejection fraction (LVEF) to < 55% was observed in eight (15.7%) patients (progressive disease gro up). In five of these eight patients, the LVDd was greater-than-or-equ al-to 60 mm and the LVEF was < 40%. Ventricular enlargement was closel y related to mortality and death due to congestive heart failure occur red in three of these patients. No deaths occurred among the 37 patien ts without significant progression of ventricular enlargement (nonprog ressive group). The annual changes of LVEF and LVDd in the progressive disease group were larger than in the nonprogressive group (LVEF -0.1 8 +/- 1.45 vs. -2.46 +/- 1.47 %/year; LVDd 0.22 +/- 0.81 vs. 1.43 +/- 0.77 mm/year). An increment in LVDs occurred earlier than the enlargem ent of the LVDd. Therefore, close attention to the LVDs seems to be im portant to detect early left ventricular morphological changes in HCM. In summary, this study indicates that HCM patients include a subgroup with symptoms resembling dilated cardiomyopathy, in whom the left ven tricle enlarges with hypofunction and in whom there is high mortality due to congestive heart failure.