Long-term outcome of coronary artery bypass grafting in patients with left ventricular dysfunction.

BACKGROUND: Coronary artery bypass grafting (CABG) is a well-accepted therapeutic strategy for patients with multivessel coronary artery disease and left ventricular dysfunction. The aim of the study was to evaluate long-term results after CABG in patients with preoperative left ventricular ejection fraction (LVEF) of 0.35 or less.

METHODS: Data from 302 consecutive patients (mean age, 62 +/- 8.7 years) with LVEF of 0.35 or less who had undergone CABG were analyzed. Epinephrine and enoximone with or without norepinephrine were used to increase cardiac index. Intra-aortic balloon pump or left ventricular assist devices, or both, were used in case of postoperative low output syndrome.

RESULTS: Complete revascularization was achieved in 298 of 302 patients (98.7%); internal thoracic artery was used in 294 (97.4%). Operative mortality was 5.3%; independent predictors of operative mortality were emergency CABG (p = 0.005), history of ventricular arrhythmias (p = 0.007), and previous anterior myocardial infarction (p = 0.05). At follow-up, all-cause mortality was 30.8%, and 10-year survival was 63% +/- 4%; independent predictors of late all-cause mortality were history of ventricular arrhythmias (p < 0.0001), chronic renal dysfunction (p = 0.0004), and diabetes mellitus (p = 0.04). Cardiac death was 20.4%, and 10-year freedom from cardiac death was 73% +/- 3.3%; independent predictors of cardiac death were history of ventricular arrhythmias (p = 0.004), chronic renal dysfunction (p = 0.03), and more than one previous anterior myocardial infarction (p = 0.004). At 80 +/- 44 months of follow-up, echocardiography showed significant LVEF improvement (0.43 +/- 0.09 versus 0.28 +/- 0.06, p < 0.0001). Ten-year freedom from myocardial infarction was 87% +/- 3%.

CONCLUSIONS: Excellent long-term results after CABG can be expected for patients with LVEF of 0.35 or less. Complete revascularization and internal thoracic artery grafting are associated with high freedom from myocardial infarction. Careful treatment of arrhythmias, diabetes, and renal dysfunction is necessary to improve long-term survival.