Abstract
In order to differentiate hypertrophic cardiomyopathy (HCM) from myocardial hypertrophy due to essential hypertension (HT), echocardiogram, apexcardiogram and phonocardiogram were simultaneously recorded in patients with HCM (n =22), HT (n = 34) and normal subjects (N) (n=22). The following early diastolic time intervals were measured : 1) IIA-O time, 2) IIA-MVO time (IRT) and 3) MVO-O time. The IIA-O time was 119 ± 9 msec in N, 159 ± 31 in HT (p < 0.001, vs N) and 228 ± 57 in HCM (p < 0.001, vs N and HT, respectively). The IIA-MVO time was 66 ± 11 msec in N, 95 ± 18 in HT (p < 0.001, vs N) and 102 ± 24 in HCM and 126 ± 48 in HCM (p < 0.001, vs N and HT, respectively). These results showed that among the early diastolic time intervals HT was abnormal only in the IIA-MVO time. On the other hand, HCM had abnormalities not only in the IIA-MVO time but also in the MVO-O time. Both the IIA-MVO and the MVO-O times in hypertrophic non-obstructive cardiomyopathy were prolonged significantly as compared to those in obstructive one. Analysis of early diastolic time intervals may be very useful to differentiate HCM, especially of the non-obstructive type, from HT.
