Management patterns of non-ST segment elevation acute coronary syndromes in relation to prior coronary revascularization

Background Contemporary guidelines support an early invasive strategy for non-ST elevation acute coronary syndrome (NSTE-ACS) patients who had prior coronary revascularization. However, little is known about the management pattern of these patients in "real world." Methods We analyzed 3 consecutive Canadian registries (ACS I, ACS II, and Global Registry of Acute Coronary Events [GRACE]/expanded-GRACE) that recruited 12,483 NSTE-ACS patients from June 1999 to December 2007. We stratified the study population according to prior coronary revascularization status into 4 groups and compared their clinical characteristics, in-hospital use of medications, and cardiac procedures. Results Of the 12,483 NSTE-ACS patients, 71.2% had no prior revascularization, 14.2% had percutaneous coronary intervention (PCI) only, 9.5% had coronary artery bypass graft surgery (CABG) only, and 5% had both PCI and CABG. Compared to their counterparts without prior revascularization, patients with previous PCI and/or CABG were more likely to be male, to have diabetes, myocardial infarction, and heart failure but less likely to have ST-segment deviation or positive cardiac biomarker on presentation. Early use of evidence-based medications was higher among patients with previous PCI only and lower among patients with previous CABG only. After adjusting for possible confounders including GRACE risk score, prior PCI was independently associated with in-hospital use of cardiac catheterization (adjusted odds ratio [OR] 1.18, 95% CI 1.04-1.34, P = .008). In contrast, previous CABG was an independent negative predictor (adjusted OR .77, 95% CI 0.68-0.87, P < .001). There was no significant interaction (P = .93) between previous PCI and CABG. Conclusions The NSTE-ACS patients with previous PCI were more likely to be treated invasively. Conversely, patients with prior CABG less frequently received invasive therapy. Future studies should determine the appropriateness of this treatment discrepancy. (Am Heart J 2010; 159: 40-6.)