Myocardial Accumulation of ⁹⁹ Tc m -Pyrophosphate and ⁹⁹ Tc m -Gluconate Compared with Morphologic Findings in Daunorubicin Treated Rabbits

In long-term daunorubicin treated rabbits increased myocardial accumulation of 99Tcm-pyrophosphate and 99Tcm-gluconate of a varying degree were recorded, visible at gamma camera examination in more than half of the animals. Chronic cardiomyopathy morphologically and topographically different from the ischemic myocardial injury was demonstrated in most animals at light microscopic examination. The myocardial abnormalities were classified in qualitative and quantitative scores and compared with the degree of isotope accumulation. The rabbits receiving a large single dose of daunorubicin had slightly increased isotope accumulation in the myocardium but no histopathologic changes.