Fatal cyclophosphamide cardiomyopathy: its clinical course and treatment.

Acute decompensating cardiomyopathy induced by cyclophosphamide is usually irreversible. To investigate the clinical course and the outcome of therapy, 13 patients (1.7%) with grade III acute cardiomyopathy and hypotension who were treated with ablative transplant regimens between January 1980 and September 1995 were analyzed. Eight of nine patients died of acute fatal restrictive cardiomyopathy with unresponsive hypotension (ARCH), whereas three of four patients who survived the initial episode died of subacute congestive heart failure (SCHF). Acute fatal restrictive cardiomyopathy was characterized with extreme sensitivity to volume overload, myocardial edema and a rapidly fatal course. It was associated with progressive, unresponsive hypotension, reduced left ventricular stroke work index (LVSWI: 29.29 +/- 9.74 g-m/beat/m2) and markedly reduced systemic and pulmonary vascular resistance indices (SVRI: 429.72 +/- 168.84, PVRI: 58.63 +/- 45.08 dyne.sec/cm5.m2). Subacute CHF was identified by myocardial edema, dilated chambers and biventricular pump failure represented by decreases in fractional shortening (FS: 19.5 +/- 4.9%). Of 10 patients who received conventional therapy, nine died and one sustained chronic CHF. One of three patients with ARCH on antioxidant therapy of ascorbic acid and theophylline survived the episode. The data suggests peripheral vascular collapse may also be responsible for fatal ARCH.