[Hypertrophic cardiomyopathy with dilatation of the left ventricle and congestive heart failure: comparison with postmyocarditis cardiomegaly and hypertensive heart failure].

In a total of 114 cases of hypertrophic cardiomyopathy (HCM), four cases were regarded to have dilated left ventricle and congestive heart failure. History of myocardial infarction was not present, and significant narrowing of coronary arteries was not detected in each case. The clinical manifestations were analyzed in the light of the differentiation from postmyocarditis cardiomyopathy (PMC: three cases) and hypertensive heart disease ( HHD : five cases). Representative case was a 47-year-old man with HCM, who showed congestive heart failure developed gradually over the last 20 years. The cardiothoracic ratio increased from 57% to 64% and high voltage of the precordial leads noted initially decreased gradually with normalization of ST-T changes. Meanwhile, a new abnormal Q wave appeared in aVL. The echocardiographic findings at the age of 47 were asymmetric septal hypertrophy and left ventricular enlargement. Myocardial biopsy of the right ventricle done at the same period revealed the marked progression of interstitial fibrosis as compared with that of 15 years ago. Clinical pictures demonstrated that PMC patients were younger than HCM or HHD patients. Abnormal Q waves were observed in three cases of HCM. In the remaining one, the Q wave was not discernible due to superimposed complete left bundle branch block. No abnormal Q waves were observed in cases of PMC and HHD . A high voltage of the left precordial leads with marked ST-T changes suggesting left ventricular hypertrophy was not seen in HCM with dilated left ventricle and HHD . Echocardiographically, the systolic anterior motion was absent in all cases. The left ventricular posterior wall in PMC and HHD was equally hypertrophied both at the apex and base, whereas in three of four cases of HCM, the apical region of the posterior wall was disproportionately hypertrophied. All cases of HCM and PMC showed asymmetric septal hypertrophy, while all the HHD cases except one showed concentric hypertrophy. In HCM, left ventricular end-diastolic dimension and left atrial dimension were increased to 60.0 +/- 6.1 mm and 45.3 +/- 9.4 mm, respectively, which were not different from those of PMC and HHD . Isometric relaxation time was prolonged to 100 msec or more in all cases of HCM, while in only one case of PMC it was prolonged and no prolongation was observed in HHD . Left ventricular wall motion revealed asynergy mainly at the hypertrophic apical area in HCM and PMC, whereas asynergy was found at the hypertrophic area, which was mostly apical, and also in the area without hypertrophy in HHD .(ABSTRACT TRUNCATED AT 400 WORDS)