Progression of hypertrophic cardiomyopathy to dilated cardiomyopathy: a case reports and review of the literatures

Left ventricular systolic function in hypertrophic cardiomyopathy (HCMP) does not usually deteriorate even in the end stage of the disease. However, occasionally cases of HCMP progress to a similar form of dilated cardiomyopathy (DCMP) with a decreased systolic function and dilated left ventricle. We report two cases of HCMP which progressed to DCMP during follow-up. Our cases have been documented by serial M-mode echocardiography which shows a prominent decrease in the left ventricular systolic function and a chamber enlargement of the left ventricle. There are various explanations of the pathogenesis of the functional and morphological myocardial deterioration of HCMP progressing to DCMP, and more cases should be studied to determine the pathogenesis and prevention of this end-stage feature of HCMP.