Cardiac function in a long-term follow-up study of moderate and severe porcine model of chronic myocardial infarction

Background. Novel therapies need to be evaluated in a relevant large animal model that mimics the clinical course and treatment in a reasonable time frame. To reliably assess therapeutic efficacy, knowledge regarding the translational model and the course of disease is needed. Methods. Landrace pigs were subjected to a transient occlusion of the proximal left circumflex artery (LCx) (n=6) or mid-left anterior descending artery (LAD) (n=6) for 150 min. Cardiac function was evaluated before by 2D echocardiography or 3D echocardiography and pressure-volume loop analysis. At 12 weeks of follow-up the heart was excised for histological analysis and infarct size calculations. Results. Directly following AMI, LVEF was severely reduced compared to baseline in the LAD group -17.1±1.6%, P=0.009 compared to only a moderate reduction in the LCx group -5.9±1.5%, P=0.02 and this effect remained unchanged during 12 weeks of follow-up. Conclusion. Two models of chronic MI, representative for different patient groups, can reproducibly be created through clinically relevant ischemia-reperfusion of the mid-LAD and proximal LCx.