Comparison of cardiac function and coronary angiography between conventional pigs and micropigs as measured by multidetector row computed tomography.

Pigs are the most likely source animals for cardiac xenotransplantation. However, an appropriate method for estimating the cardiac function of micropigs had not been established. Computed tomography (CT) analysis aimed at estimating cardiac function and assessing the coronary arteries has not been carried out in micropigs. This study determined the feasibility of evaluating cardiac function in a micropig model using multidetector row computed tomography (MDCT) and compared the cardiac function values with those of conventional pigs. The mean age of the conventional pigs and micropigs was approximately 80 days and approximately 360 days, respectively. The mean body weight in the conventional pigs and micropigs was 29.70 +/- 0.73 and 34.10 +/- 0.98 kg, respectively. Cardiac MDCT detected ejection fractions of 52.93 +/- 3.10% and 59.00 +/- 5.56% and cardiac outputs of 1.46 +/- 0.64 l/min and 1.21 +/- 0.24 l/min in conventional pigs and micropigs, respectively. There were no significant differences in cardiac function between conventional pigs and micropigs in the reconstructed CT images. There were also no differences in the coronary angiographic images obtained by MDCT. It is expected that the results of this study will help improve understanding of cardiac function in micropigs. The data presented in this study suggest that MDCT is a feasible method for evaluating cardiac function in micropigs.