[Pulsed Doppler echocardiographic assessment of diastolic left ventricular hemodynamics in hypertrophic cardiomyopathy: relationship between the mode of left ventricular filling and the distribution of left ventricular hypertrophy].
In order to clarify left ventricular relaxation and filling in different types of hypertrophic cardiomyopathy (HCM), velocity patterns of blood flow at the inflow tract of the left ventricle (LV) were recorded by pulsed Doppler echocardiography and compared with those of normal subjects (26 cases). Forty-one patients with HCM were classified into the following 4 groups according to the distribution of LV hypertrophy and the evidence of cavity obstruction of the LV; with asymmetric septal hypertrophy (ASH: 15 patients), apical hypertrophy (APH: 10), diffuse hypertrophy ( DIH : five) and obstruction of the LV cavity (HOCM: 11). The HOCM group consisted of five cases of ASH type and six of APH or DIH type. Acceleration time (AT), deceleration time (DT) and the A/D ratio were measured on the pulsed Doppler echocardiogram. The M-mode echogram of the LV was recorded and subsequently digitized to obtain peak LV filling rate. The results were as follows: AT was significantly prolonged in 4 groups of HCM compared with that of the normal subjects. But there was no significant difference in AT among various HCM groups. DT was markedly prolonged in 4 groups of HCM compared with that of the normal subjects, but DT was significantly shortened in the ASH group compared with that of the APH or HOCM group. DT of the HOCM group was divided into the following 2 types according to the duration; normal or slightly prolonged DT (three cases) and markedly prolonged DT (eight). The former group belonged to the ASH type of LV hypertrophy in all cases, and two of them showed a third heart sound. An apical diastolic murmur was recorded in four patients of the ASH group, and six of the HOCM (five cases with ASH type and one with APH type). The A/D ratio was significantly increased in 4 groups of HCM compared with that of the normal subjects. But there was no significant difference among HCM groups. Diastolic descent rate (DDR) of the mitral valve echogram was significantly reduced in 4 groups of HCM compared with that of the normal subjects, particularly in the ASH and HOCM groups. DDR was roughly correlated with DT in the HCM group (r = -0.40, p less than 0.02). Peak LV filling rate was markedly decreased in the ASH, APH and HOCM groups compared with that of the normal subjects. There was a significant negative correlation between peak LV filling rate and DT (r = -0.49, p less than 0.01). In conclusion, the mode of LV filling in HCM showed various patterns according to the location of ventricular hypertrophy and the presence of cavity obstruction of the LV.(ABSTRACT TRUNCATED AT 400 WORDS)
D000328:Adult; D001783:Blood Flow Velocity; D002312:Cardiomyopathy, Hypertrophic / Q000503:physiopathology*; D003971:Diastole; D004452:Echocardiography / Q000379:methods*; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008875:Middle Aged; D008943:Mitral Valve / Q000503:physiopathology; D009200:Myocardial Contraction