A Close-Chest Method for Creating Myocardial Ischemia and Reperfusion Injury in Swine

Objective To create a close-chest model of myocardial ischemia and reperfusion in pigs, using the technique of balloon catheter inflation and deflation, and to report experiences and pitfalls. Methods In 26 minipigs, a balloon catheter was advanced into the left descending coronary artery (LAD) via the femoral artery sheath and positioned at the midsection of LAD. LAD was occluded for 2 h and then reperfused. After 14 d, the animals were euthanized and the hearts were stained with triphenyltetrazolium chloride to identify infarct area. The causes for failure were analyzed. Results Seventeen pigs (65.38%) completed the experiment. The success rate increased from 52.94% in the initial 17 pigs to 88.89% in the last 9 pigs. The mean size of infarction was (16.4±4.1)% of the total left ventricular area. The direct cause for failure was lethal ventricular fibrillation (VF), with different underlying mechanisms according to different time of episode. Appropriate anticoagulation, well-controlled heart rate and proper size of balloon catheter were important factors for avoiding failure. Conclusion The technique of balloon inflation and deflation can be successfully used for creating the close-chest model of myocardial ischemia and reperfusion in pigs. This model is suitable for studies on myocardial infarction and early reperfusion, avoiding the disadvantages of open-chest models.