Abstract 4137267: A novel reproducible low-cost model of acute myocardial infarction in swine

Background: Traditional open- and closed-chest methods for inducing acute myocardial infarction (AMI) in pigs typically require extensive and expensive instrumentation, including ventilators and inhalation anesthesia. This study aims to evaluate a reproducible and low-cost model for AMI in pigs using lower hemisternotomy. Methods: Twenty Yorkshire swine (15-20 kg, 45-50 days of age) underwent permanent ligation of the roots of the first and second diagonal branches of the left anterior descending coronary artery. The procedure was performed under intramuscular anesthesia (1ml 0.5mg/kg Zoletil™ and 2ml 10mg/kg xylazine hydrochloride) with spontaneous respiration. Cardiac function was assessed via echocardiography and cardiac PET/MRI scans at 1 and 4 weeks post-MI. Heart tissue was collected for pathological analysis to evaluate the establishment of the AMI model. Results: All animals exhibited ECG changes, including premature ventricular complexes and ST-segment elevation immediately after ligation. No ventricular tachycardia and fibrillation was observed during the operation. No animals (0%) died during infarct creation. The "Skin-to-Skin" procedure time was 18±3.3 minutes. this procedure produced an infarction that occupies ~10% of the left ventricular mass accompanied with the decrease of LV heart function and LV anterior wall thickness 4 weeks post-MI. Conclusions: This novel low-cost technique provides reproducible acute coronary artery occlusion at a selected location with subsequent AMI. It avoids ventilation, inhalation anesthesia, major surgery and does not require expensive instrumentation for intracoronary intervention.