A 45-year-old man receives a cardiac allograft for dilated cardiomyopathy. He has no problems with rejection, but 5 years later he has worsening exercise tolerance with increasing dyspnea and peripheral edema. Echocardiography shows a reduced ejection fraction of 35%. Which of the following pathologic abnormalities has he most likely developed in the allograft?
Amyloidosis Constrictive pericarditis Coronary arteriopathy Non-Hodgkin lymphoma