THE DIAGNOSTIC ACCURACY OF RADIOGRAPHIC CARDIAC INDICES IN THE ASSESSMENT OF CARDIOMEGALY AND LEFT ATRIAL ENLARGEMENT IN RATS WITH DILATED CARDIOMYOPATHY: AN EXPERIMENTAL STUDY

The purpose of this study was to determine the diagnostic value of the ver-tebral heart score (VHS), radiographic left atrial dimension (RLAD), and vertebral left atrial size (VLAS) in the radiographic evaluation of doxorubicin-induced dilated cardio-myopathy (DCM) in rats. The animals were allocated into two experimental groups, a DCM group (n=100), which received weekly injections of doxorubicin (2 mg/kg per dose intraperitoneally [ip]) over nine weeks, and a control group (n=18) receiving an appropri-ate volume of 0.9% saline ip. Radiographic cardiac indices (VHS, RLAD, VLAS) were measured two weeks after the final injection, and cardiac morphological parameters (heart weight [HW], heart weight:body weight ratio [HBW], and heart weight:tibial length ratio [HTL]) were determined after sacrifice in all surviving rats (17 control and 54 DCM). Correlations were calculated between the indices and parameters, as well as their sen-sitivity and specificity in detecting cardiomegaly and left atrial enlargement (LAE) with the three classifiers (HW≤0.96 g, HBW≤235, and HTL≤201). A powerful negative correla-tion was observed between the indices and parameters (rs≥-0.711, P