Frequency and extent of contraction band necrosis in orthotopically transplanted human hearts. A morphometric study

Background: The aims of the present study are to quantify forms of myocardial and coronary changes found at postmortem and to discuss their significance in relation to causes of death and cardiac arrest in orthotopic transplanted human hearts. Methods: The examined material included (1) 46 orthotopic transplanted human hearts and, as "controls", hearts from (2) 25 sudden/unexpected coronary death cases, 38 patients with acquired immunodeficiency syndrome, 34 subjects with "silent" Chagas' disease who died suddenly, 27 non cardiac patients who died from intracranial hemorrhage due to a ruptured cerebral aneurysm and 45 healthy subjects dead from head trauma. Results: Contraction band necrosis was observed in 85% of transplanted hearts, 66% of AIDS cases and in 100% Chagas' disease, 89% intracranial hemorrhage, 71% sudden coronary death, and 18% normal head trauma cases. Foci of lymphocytic infiltrate were present in 89% of transplanted heart, 50% AIDS, 100% Chagas' disease, 37% intracranial hemorrage and 64% head trauma groups. An allograft coronary vasculopathy was observed in four transplanted hearts with a survival greater than 202 days. In another 12 cases, who survived more than one year, atherosclerosis was the only coronary lesion found. No relation was observed between coronary lesions of any degree of stenosis and myocardial injuries. Conclusions: In the group studied acute rejection was the least frequent cause (2%) of graft failure at any time following transplantation and coronary vasculopathy a questionable cause of it in four cases. Rather, contraction band necrosis as an expression of catecholamine myotoxicity seemed to play a role in graft failure related to increased myocardial catecholamine sensitivity after global denervation.