Trends and clinical outcomes of patients with established coronary artery disease presenting with acute coronary syndromes.

Abstract

Background: Patients with known coronary artery disease are at high risk for future cardiovascular events. In patients presenting with acute coronary syndromes (ACS), the prognostic significance of having established CAD is unknown.

Methods: Consecutive patients from the Melbourne Interventional Group registry who presented with ACS and underwent PCI between 2005 and 2015 were included. Patients with a history of myocardial infarction, PCI or bypass surgery were included in the established CAD cohort. The primary endpoint was 12-month mortality, myocardial infarction and major adverse cardiovascular events.

Results: Of the 12,878 patients included, 3,542 had established CAD on presentation with ACS. Over a 10-year period, there has been a decrease in patients with ACS with established CAD (30.7% to 25.2%; p-for-trend < 0.01). These patients were older (67.5 ± 12.0 vs. 63.1 ± 12.5 years; p < 0.001) and had higher rates of diabetes, stroke, renal impairment, left ventricular dysfunction and peripheral vascular disease (all p < 0.001). At 12-months, those with established CAD had higher mortality (7.9% vs. 5.4%; p < 0.001), recurrent MI (8.4% vs. 3.3%; p < 0.001), target vessel revascularisation (8.7% vs. 5.5%; p < 0.001), stroke (1.5% vs. 0.8%; p = 0.001) and MACE (20.2% vs. 12.8%; p < 0.001). On multivariate analysis, established CAD was an independent risk factor for MACE (OR 1.4, 95% CI 1.23-1.58; p = < 0.001) but not for mortality (OR 1.08; 95% CI 0.77-1.52; p = 0.66).

Conclusion: Although patients with established CAD have more co-morbidities, known CAD remains an independent predictor of MACE after adjustment for these factors. Close monitoring and intense optimisation of medical therapy is warranted in this patient group.