RESUMO
The development of heart failure is the most powerful predictor of long-term mortality in patients surviving acute myocardial infarction (MI). There is an unmet clinical need for prevention and therapy of post-myocardial infarction heart failure (post-MI HF). Clinically relevant pig models of post-MI HF are prerequisites for final proof-of-concept studies before entering into clinical trials in drug and medical device development. Here we aimed to characterize a closed-chest porcine model of post-MI HF in adult Göttingen minipigs with long-term follow-up including serial cardiac magnetic resonance imaging (CMRI) and to compare it with the commonly used Landrace pig model. MI was induced by intraluminal balloon occlusion of the left anterior descending coronary artery for 120 min in Göttingen minipigs and for 90 min in Landrace pigs, followed by reperfusion. CMRI was performed to assess cardiac morphology and function at baseline in both breeds and at 3 and 6 months in Göttingen minipigs and at 2 months in Landrace pigs, respectively. Scar sizes were comparable in the two breeds, but MI resulted in a significant decrease of left ventricular ejection fraction (LVEF) only in Göttingen minipigs, while Landrace pigs did not show a reduction of LVEF. Right ventricular (RV) ejection fraction increased in both breeds despite the negligible RV scar sizes. In contrast to the significant increase of left ventricular end-diastolic (LVED) mass in Landrace pigs at 2 months, Göttingen minipigs showed a slight increase in LVED mass only at 6 months. In summary, this is the first characterization of post-MI HF in Göttingen minipigs in comparison to Landrace pigs, showing that the Göttingen minipig model reflects post-MI HF parameters comparable to the human pathology. We conclude that the Göttingen minipig model is superior to the Landrace pig model to study the development of post-MI HF.
