Treatment of acute right coronary artery occlusion during anesthesia

Purpose: Perioperative coronary artery occlusion is a potentially dangerous complication causing myocardial infarction and circulatory collapse. We re port a case showing severe ST segment depression in leads II and V5 during anesthesia. Diltiazem and nifedipine, but not nitroglycerine, partially imp roved the ST changes which were normalized by a percutaneous cardiopulmonar y system (PCPS). Clinical Features: A 71-yr-old man with cerebrovascular disease was schedul ed for coronary artery bypass grafting(CABG). Past medical history included myocardial infarction due to right coronary artery(RCA) occlusion. Both th e femoral artery and vein were cannulated percutaneously before operation a nd the PCPS was prepared as a back-up system. Depression of the ST segments in leads V5 and II was observed following heparinization. Although hemodyn amic stability was maintained with continuous infusion of catecholamines, t he ST changes were not improved by intravenous nitroglycerine. Intravenous diltiazem followed by nasal nifedipine partially improved the ST changes. T he changes were normalized after induction of PCPS. No neurological complic ations were observed. The postoperative coronary angiography confirmed the total occlusion of RCA. Conclusion: Calcium channel blockers were more effective than nitroglycerin e in treating perioperative ST depression. However, none of them produced c omplete reversal of the ischemic changes which were normalized with PCPS.