Experimental myocardial infarction in dogs. Description of a closed chest technique.

SUMMARY A closed chest technique for production of myocardial infarction in dogs is described. After isolation of the left carotid artery, selective coronary cineangiography is performed. A guide wire is then inserted into the catheter and advanced into the circumflex or anterior descending branch of the left coronary artery. The catheter is temporarily removed. A specially designed, siliconized, stainless steel cylinder is then inserted over the guide wire. The catheter is reinserted and is used to push, direct, and lodge the stainless steel cylinder into the anterior descending or the circumflex artery. The dogs are heparinized before, and for 3 days subsequent to, constriction. Ventricular arrhyth-mias are treated with procainamide. Coronary cineangiograms and serial electrocardio-grams are obtained after coronary artery constriction. This technique provides an accurate nmodel for research in the field of myocardial infarction. Additional Indexing Words: Myocardial ischemia Animal model for myocardial infarction THE PRODUCTION of acute myocardial infarction or ischemia in animals is of particular importance in research related to coronary artery disease. In this regard a reliable and accurate experimental model should closely simulate the clinical situation. Ideally, an animal model should provide the following conditions: (1) The technique of producing myocardial infarction or ischemia should not need thoracotomy. (2) The technique should have the versatility of producing the lesion in various sites of coronary arteries. (3) Physiological studies, such as determination of coronary blood flow, especially distal to the narrowing (by injection of isotope indicators into the narrowed vessel Chronic ischemic heart Coronary blood flow and precordial counting or serial coronary sinus sampling), and cardiac metabolic studies should be feasible. It is the purpose of this preliminary communication to describe a closed-chest technique for producing myocardial infarction in dogs. Narrowing of the coronary artery and subsequent occlusion were produced by insertion of a stainless steel cylinder into a branch of the left coronary artery. Methods Stainless steel cylinders were polished and siliconized. They measured 4 mm in length, 3.25 mm in external diameter, and 2.0 mm in internal diameter. They were smoothly tapered for ease of insertion into the coronary artery.