OBJECTIVETo investigate the morphological characteristics and types of ventricular wall with dysplastic development and their associations to primary cardiomyopathy.

METHODSNinety-two hearts from heart transplant patients were studied soon after explanation from 2004 to 2007. Gross examination/measurement, histopathology and photography were performed.

RESULTSDysplastic development of ventricular wall could be evidenced in patients with various heart diseases but more often in patients with primary cardiomyopathy, though the extension and distribution of dysplastic development of ventricular wall varied between patients with or without primary cardiomyopathy. Severe dysplastic development of ventricular wall is associated with clinical dysplastic cardiomyopathy. The range of extension and degree of dysplasia in the ventricular wall correlated positively to heart dilation/failure and time point of heart failure development. The incidence of severe ventricular wall dysplasia was 27.17% in all transplanted hearts and was 43.1% (25/58) in hearts diagnosed as primary cardiomyopathy (P < 0.05). The main pathological changes of dysplastic hearts were: (1) extensive proliferative hypertrophy of the heart wall, (2) fibrous/fat or fat/fibrous tissue replacement of normal myocardium, (3) disarrangement of myocardial fibers, (4) dysplastic change in the medium-sized intramural arteries. Dysplastic cardiomyopathy was presented mainly as a combination of several forms of dysplasia. The same clinical manifestations of dysplastic cardiomyopathy patients did not always show the same pathologic changes. Fibrous-fat tissue replacement was commonly found in dilated cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy. Disarrangement of myocardium was often accompanied by hypertrophic cardiomyopathy. Dysplasia of intramural arteries could result in heart dilatation due to myocardial ischemia.

CONCLUSIONDysplasia of ventricular wall is a common variation of heart structure. Only severe or diffuse types of dysplasia is associated with cardiomyopathy, especially primary cardiomyopathy.