Comparison of clinical and morphologic cardiac findings in patients having cardiac transplantation for ischemic cardiomyopathy, idiopathic dilated cardiomyopathy, and dilated hypertrophic cardiomyopathy.

This article compares intergroup and intragroup clinical and morphologic findings in patients with ischemic cardiomyopathy (IC), idiopathic dilated cardiomyopathy (IDC), and dilated hypertrophic cardiomyopathy (HC) undergoing cardiac transplantation (CT). Few previous publications have described findings in native hearts explanted at the time of CT. The explanted heart in 92 patients having CT was examined in uniform manner with particular attention to the sizes of the ventricular cavities and the presence of and extent of ventricular scarring. Of the 92 hearts examined, 47 had IC, 35 had IDC, and 10 had dilated HC. Although considerable degrees of intragroup variation occurred, the mean degree of left ventricular dilatation was similar among the patients with IC, IDC, and dilated HC. All patients with IC had left ventricular free wall scarring more extensive than that involving the ventricular septum, but the intragroup variation in the amounts of scarring was considerable. Nine of the 10 patients with dilated HC also had ventricular wall scarring, but it was more extensive in the ventricular septum than in the left ventricular free wall and involvement of the right ventricular wall also was present. Eight (23%) of the 35 IDC patients also had grossly visible ventricular scars but they were small and only 1 of the 8 had coronary narrowing and that was not in the distribution of the scarring. Narrowing of 1 or more epicardial coronary arteries >75% in cross-sectional area by plaque was present in all 47 IC patients, in 8 of the 35 IDC patients (7 had no ventricular scars), and in none of the 10 dilated HC patients. Coronary angiography was the major clinical tool allowing separation of the IC, IDC, and HC patients. Coronary angiography did not detect narrowing in any of the 8 patients with IDC who were found to have coronary narrowing on anatomic study. Thus, among patients with IC, IDC, and dilated HC having CT, distinctive anatomic features allow separation of patients with IC, IDC, and dilated HC, but within each group considerable variation in left ventricular cavity size and extent of ventricular scarring occurs.