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DISSCUSION
I. Adriamvcin CardiomvoPathv
Adriamycin is a drug of choice widely used in the treatment of a number of
human malignancies. Its therapeutic potential is limited by the development of a dosedependent
drug-induced cardiomyopathy. The latter has the potential of progressing into
therapy-resistant congestive heart failure (Lefrak et aI. 1,973; Minow and Gottlieb 1975;
Singal and Iliskovic 1998). These characteristics have led to limiting the drug-dose to the
cumulative levels below 550 mg/m2 body surface atea (Lefrak et al. 1973) (Von Hoff et
al. 1979). However, a strict adherence to this empirical dose can exclude those patients
who can profit from a higher dose without the risk of heart disease. Conversely, some
other patients, because of the presence of risk factors, may develop adriamycin-induced
cardiomyopathy despite the usage of the dose that was significantly lower than the
limitation dose. Thus, there is a great need for a better understanding of the
pathophysiolo gy of this drug-induced condition.
II. Animal model
In this study, we used the rat model of adriamycin induced cardiomyopathy which
is reliably reproducible and mimics many features of cardiomyopathy seen in patients. ln
the ADR treated animals in the present study, the development of cardiomyopathy was
confirmed by clinical, hemodynamic and echocardiography data. Presence of significant
amount of ascites and labored breathing indicated the development of congestive heart
failure. The cardiac cathetenzation study showed that adriamycin administration caused a
significant decrease in the left ventricular systolic pressure and a significant increase in
the left ventricular end diastolic pressure. Development of congestive heart failure in the
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