[Acute coronary syndrome].

The first choice of interventional treatment for acute coronary syndrome is percutaneous coronary intervention (PCI), especially when the patient is in cardiogenic shock. In cases of acute myocardial infarction, emergency coronary artery bypass grafting (CABG) is indicated when left main trunk (LMT) lesion or severe triple-vessel disease is left after PCI combined with residual or recurrent ischemic angina and/or ST-T change in electrocardiogram (ECG). Similarly, in cases of unstable angina, emergency CABG is indicated when LMT or LMT equivalent (proximal left anterior descending branch and left circumflex branch) is the culprit lesion or when severe triple-vessel disease exists. Urgency of operation and existence of cardiogenic shock are major operative risk factors of CABG in patients with acute coronary syndrome. The surgical mortality of such cases is much higher than that of elective surgery for chronic angina. As employment of cardiopulmonary bypass (CPB) and achievement of cardioplegic arrest is one of the major causes of surgical mortality, off-pump CABG (OPCAB) using no CPB nor cardioplegic solution has recently become popular. OPCAB, however, is difficult to perform when the hemodynamic state is unstable. On-pump beating heart CABG is an alternative technique of choice because it not only stabilizes the hemodynamic state but also prevents myocardial ischemia/reperfusion injury. These beating heart CABG techniques will improve surgical outcome of acute coronary syndrome.