10775 Background: Cardiotoxicity is a well-known side effect of several cytotoxic drugs especially of the anthracyclines and can lead to long term morbidity. Endomyocardial biopsy is the only specific test for early diagnosis of anthracycline-induce toxicity. Efforts are continuing on finding a more sensitive and reliable predictor of eventual clinic cardiac dysfunction. Therefore, it is crucial that careful monitoring to identify those patients patients who are at risk of developing unpredectible and some times-irreversible dysfunction. Serial measurement of left ventricular ejection fraction by radionuclide angiography remains a useful and widely adopted modality in monitoring patients that are receiving doxorubicin. Objective: To investigate the value of 99mTc-MIBI myocardial perfusion tomography to detect myocardial damage in patients with breast cancer under chemotherapy. Methods: Thirty patients were examined from May to December 2000 by electrocardiogram (ECG), nuclear angiography for detecting left ventricular ejection fraction (LVEF) and 99mTc-MIBI myocardial perfusion was performed before chemotherapy and after chemotherapy. Results: Fifteen patients were treated by continuos infusion over 24 hr, nine patients over 48 hr and 6 patients were treated by bolus. The patients presented with a decrease of > or = 9% in absolute ejection fraction at 200–320 mg/m2 with 99mTc-MIBI and 5% with nuclear angiography. Gated myocardial perfusion scintigraphy results were abnormal in four patients (12.9%). All patients were treated by continuos infusion and the radiotherapy was absent. Other factors were investigated: hypertension, diabetes, smoker and obesity. Conclusions: 99 mTc-MIBI studies are helpful in the assessment of doxorubicin cardiotocixity. Anthracyclines induced myocite injury symptomatic or asymptomatic; uptake at intermediate cumulative doses identifies patients at risk of cardiotoxicity before ejection fraction deteriorates. The 99-mTc-MI BI imaging may be a sensitive method for non invasive visualization of myocardial cell damage and useful in the early diagnosis of specific heart muscle disease. Doxorubicin cause silent myocardial ischemia. No significant financial relationships to disclose.
13N-AMMONIA PET-DERIVED VENTRICULAR SYNCHRONY CORRELATES WITH MYOCARDIAL PERFUSION RESERVE BETTER THAN LEFT VENTRICULAR EJECTION FRACTION: A STUDY IN INFARCTED PATIENTS
