Surgical management of acute myocardial ischemia following percutaneous transluminal coronary angioplasty. Role of the intra-aortic balloon pump.

Acute myocardial ischemia is a serious complication of percutaneous transluminal coronary angioplasty, often requiring emergency myocardial revascularization. Since our initial report of 17 such patients, we have encountered an additional 32 patients requiring emergency myocardial revascularization since September, 1981. The indication for emergency myocardial revascularization was ischemic chest pain in all 32 patients. Percutaneous transluminal coronary angioplasty resulted in injury to the right coronary artery in 11 patients, the left anterior descending artery in 19 patients, and the left main artery in two patients. The onset of ischemia was immediate in 26 patients but delayed up to 22 hours in six patients. Chest pain was associated with ST-segment elevation in 21 patients, hypotension in 7 patients, and cardiac arrest in 6 patients. Immediate intra-aortic balloon pumping was instituted in the angioplasty suite in 16 patients. The mean time from onset of ischemia to completed revascularization was 156 minutes with a mean of 1.6 grafts performed per patient. Seventeen patients (53%) had enzyme evidence of myocardial infarction postoperatively, with a significantly higher (p less than 0.01) incidence of myocardial infarction in those patients with preoperative ST elevation (76% versus 9%). In the 21 patients with ST-segment elevation, the incidence of Q wave infarction was 20% (3/15) with balloon pumping and 50% (3/6) without balloon pumping. Complications associated with intra-aortic balloon pumping occurred in one patient (6%). There were no hospital or late deaths with follow-up extending 16 months. The spectrum of injury resulting from percutaneous transluminal coronary angioplasty extends from chest pain alone to severe transmural ischemia with hypotension or cardiac arrest. Presentation may be immediate or delayed. Urgent emergency myocardial revascularization remains the accepted therapy for this complication. Immediate preoperative intra-aortic balloon pumping is a useful adjunct to emergency myocardial revascularization in the group of patients with acute ischemia and ST-segment elevation.