Background: Patients with previous coronary artery bypass graft surgery (CABG) have been classified as a high-risk subset of patients who experience non-ST elevation acute coronary syndrome (ACS). Recent studies suggest that an early invasive strategy is beneficial in moderate- and high-risk patients with non-ST elevation ACS. We hypothesized that an early invasive strategy is associated with improved outcomes in patients with non-ST elevation ACS with prior CABG.
Methods and results: In the Treat Angina with Aggrastat and determine Cost of Therapy with an Invasive or Conservative Strategy-Thrombolysis in Myocardial Infarction 18 trial (TACTICS-TIMI 18), 2220 patients with non-ST segment elevation ACS were randomized to an early invasive or conservative (selectively invasive) strategy. All patients were treated with aspirin, heparin, and tirofiban. Four hundred eighty-four (22%) of these patients had undergone CABG before enrollment. We analyzed whether patients with previous CABG had different 6-month outcomes and whether an early invasive strategy was associated with an improvement in long-term outcomes. Prior CABG was associated with a higher risk of adverse outcomes by 6 months, including a higher rate of readmission for ACS (17.4% vs 11.0%, P < 0.001) and a higher incidence of the composite end point of death, myocardial infarction, or rehospitalization for ACS (22.3% vs 16.4%, P = 0.002). There was a trend toward a higher incidence of myocardial infarction (7.1% vs 5.3%, P = 0.051). An early invasive strategy was associated with a reduction in the composite of death or myocardial infarction (odds ratio [OR], 0.58; 95% confidence interval [CI], 0.31-1.0; P = 0.089) and a significant reduction in the incidence of myocardial infarction at 6 months (OR, 0.44; 95% CI, 0.21-0.93; P=0.032).
Conclusions: Patients with non-ST segment elevation ACS who have had previous CABG are a high-risk subset. An early invasive strategy reduces risk of myocardial infarction in this high-risk group.