HIGH-DOSE CYCLOPHOSPHAMIDE-INDUCED MYOCARDIAL DAMAGE DURING BMT - ASSESSMENT BY POSITRON EMISSION TOMOGRAPHY

Despite its potential to cause myocardial damage, high-dose CY in dose s up to 200 mg/kg is an integral part of preparative regimens for BMT. Conventional tests, such as an electrocardiogram or echocardiogram, h ave lacked sensitivity in prediction of cardiotoxicity in this patient population. We prospectively compared serial electrocardiograms and p ositron emission tomography scans before and after CY administration t o investigate the possible changes in N-13-ammonia perfusion and F-18- 2-deoxyglucose metabolism after CY administration in 12 consecutive pa tients undergoing BMT. Neither global nor regional changes in myocardi al N-13 ammonia and 18-fluorodeoxyglucose were significant when compar ed with baseline studies and control studies (p < 0.05). In a single p atient, however, a substantial increase in N-13-ammonia perfusion was seen in the inferior region simultaneously with electrocardiographic T wave inversions in the inferior leads. These changes may be due to al terations in myocardial blood flow or membrane permeability. PET scann ing may be a useful adjunct in evaluating CY cardiotoxicity, although further investigations are needed to elucidate its role in clinical pr actice.