Surgical treatment of acute myocardial infarction

The role of surgical revascularization in the treatment of acute myocardial infarction (AMI) has changed considerably over the last 30 years along with improvement in intraoperative management and techniques of myocardial protection. The aim of this work was to analyze the long-term results of our experience of emergency myocardial surgical revascularization for AMI.

Between January 1986 and October 2003, 237 patients (85.3% males; mean age 59.6 +/- 9.6 years) underwent emergency coronary artery bypass graft for severe AMI. At admission 82 patients (34.6%) were in cardiogenic shock, while 124 patients (52.3%) presented major preoperative complications (acute pulmonary edema, mechanical ventilation, intra-aortic counterpulsation, cardiac arrest). Preoperative intra-aortic counterpulsation was performed in 125 patients (52.7%). The mean time interval between symptom onset and surgery was 9.4 hours. Three-vessel disease was detected in 107 patients (45%), with main left stenosis in 12.9%.

There were overall 50 hospital deaths (21.1%). Amongst patients with major preoperative complications, mortality was 36.2% (45 cases out of 124); mortality for cardiogenic shock was 40.2% (33 patients out of 82). Survival of the first 140 patients undergoing operation and then discharged was 97.8% at 1 year and 79.6% at 5 years. The survival rate of the first 60 patients in cardiogenic shock operated on and then discharged is 98.8% at 1 year and 81.2% at 5 years. The ejection fraction in 102 echocardiographically controlled patients was 37.2 +/- 8.5% preoperatively and 44.0 +/- 10.1% at pre-discharge (p = 0.0001).

Surgical revascularization for AMI, especially if complicated by cardiogenic shock, is a valid therapeutic option that carries a high periprocedural risk but that is balanced by a satisfactory late survival. A more precise patient's risk assessment at admission, improvement of surgical and myocardial protection techniques, extensive use of intra-aortic counterpulsation, and new circulatory support when needed, can improve outcomes and late survival.