Progressive cardiac dysfunction in adriamycin-induced cardiomyopathy rats

Cardiotoxicity is a limiting factor in the treatment of cancer with adriamy cin. We administered adriamycin by a method which minimizes the risk of per itonitis in an adriamycin-induced cardiomyopathy rat model. Sixty male Wist ar rats were given 1 mg/kg of adriamycin intraperitoneally 1.5 times over a 3-week period (total dose, 15 mg/kg) to induce the cardiomyopathy model. F ifteen control rats received 10 ml/kg body wt. saline 15 times over 3 weeks . The animals were observed for 12 weeks and assessed for mortality, and ca rdiac volume and function was analyzed by echocardiography at 4, 8, and 12 weeks. In rats treated with adriamycin, the cumulative :mortality was 35.8% while in the controls, none of the rats died. Left ventricular diameter of the systole (LVDs) was significantly increased at 4 weeks (4.5 vs. 3.3 mm; P < 0.001). Left ventricular diameter of the diastole (LVDd) was significa ntly increased at 12 weeks (7.9 vs. 7.0 mm; P < 0.01) and the % fractional shortening (FS) was significantly decreased at 8 weeks (33.4% vs. 50.0%; P < 0.01) in the adriamycin-treated rats. This administration method appears to be useful for investigating the cardiac effect of adriamycin while avoid ing the influence of peritonitis typically caused by an intraperitoneal inj ection of higher single doses of adriamycin. (C) 2000 European Society of C ardiology. All rights reserved.