Serial radionuclide assessment of doxorubicin cardiotoxicity in cancer patients with abnormal baseline resting left ventricular performance.

While previous studies have demonstrated that sequential radionuclide angiocardiography allows identification of patients at risk for development of congestive heart failure and prediction of the appropriate time for safe discontinuation of doxorubicin, these studies were based predominantly on patients with normal baseline left ventricular performance. This study addresses the use of doxorubicin in patients with abnormal left ventricular ejection fraction (less than 55%) prior to drug administration. Of 337 patients referred for evaluation of left ventricular performance prior to doxorubicin therapy during a 36-month period, 45 (13%) had abnormal baseline left ventricular performance determined by first-pass radionuclide angiocardiography. Sixteen patients had antecedent cardiovascular disease, and 16 patients had received thoracic radiation, while only four patients had both. Left ventricular ejection fraction in each of these subgroups was comparable. In 7 of 16 patients who only had a baseline determination of left ventricular function, doxorubicin was not administered because of a significant concern for the potential risk of doxorubicin cardiotoxicity. In the group of 29 patients followed sequentially over 3 to 15 months (mean, 6 months), there was no significant difference between baseline and final left ventricular ejection fraction (48 +/- 5 vs 47 +/- 9%, p = NS). Only in the 12 patients who received greater than or equal to 350 mg/m2 cumulative dose was there a small but significant fall in left ventricular ejection fraction (48 +/- 4 vs 43 +/- 8%, p less than 0.05). Only one patient developed congestive heart failure. This study demonstrates that doxorubicin can be administered safely to patients with abnormal baseline left ventricular performance using serial radionuclide studies as a means of monitoring therapy. Guidelines for doxorubicin therapy in these patients have been developed.