[Doxorubicin-induced myocardial damage in elderly patients with hematologic malignancies]

Cardiac function was evaluated in 53 elderly patients with hematologic malignancies who were being treated with doxorubicin (DXR). The left ventricular ejection fraction was measured by radionuclide angiocardiography, the washout rate by 123I-MIBG myocardial SPECT, the extent and severity scores by 123I-BMIPP myocardial SPECT, and the frequency of premature ventricular contractions by Holter electrocardiography. 1) In some patients, both the washout rate and the extent and severity scores were abnormally high before treatment. 2) Because the washout rate correlated with the total dose of DXR, it may be an early indicator of cardiac sympathetic nervous dysfunction. 3) The left ventricular ejection fraction correlated with the extent and severity scores, but not with the washout rate or with the frequency of premature ventricular contractions. 4) The washout rate correlated with the frequency of premature ventricular contractions. These data show that elderly patients had abnormal cardiac function even before treatment with DXR; that cardiac sympathetic dysfunction and cardiac mitochondrial dysfunction developed at total DXR doses of 250 to 300 mg/m2 or higher; and that the left ventricular ejection fraction was less than or equal to 50% in many patients. Consequently, when DXR is used to treat elderly patients, multimodal evaluation of cardiac function is necessary to detect cardiotoxicity and to determine the optimal total dose and the optimal dosage.