Abstract 14076: Acute Stent Thrombosis Resulting in St Elevation Myocardial Infarction (STEMI) is Associated With Worse Clinical Outcomes Than STEMI Due to Native Coronary Thrombosis
Background: Stent thrombosis (ST) is a recognized cause of STEMI in patients with previous PCI. The incidence is increasing and outcomes are not well characterized. We compared STEMI due to ST versus de novo coronary thrombosis to evaluate clinical outcome.
Methods: Information was analysed from a prospective database on 2,421 patients who underwent Primary PCI for STEMI between 2003-2010 at a London centre. Information was entered at presentation & outcome assessed by all-cause mortality via the BCIS/CCAD national audit.
Results: ST caused 7.4% (180/2421) of all STEMIs with increasing frequency over time (5.4% in 2005 to 9.8% 2009). ST occurred early (0-30d) in 36% (65/180), late (30d-1 yr) in 22% (40/180) and very late (> 1yr) in 42% (75/180) of pts. Drug-eluting stents accounted for 48% of ST overall. Causes included early discontinuation of anti-platelets (11%), under-deployment of previous stents (22%) and underlying prothrombotic conditions (6%). Pts with ST compared to native artery occlusion had higher rates of prior MI (53.9% vs 11%, p<0.0001) and multi-vessel disease (59.8% vs 51.7%, p=0.04). There was no difference in age, diabetes or cardiogenic shock. Infarct size based on peak enzyme markers was similar. Angiographic success (postprocedural TIMI grade III flow) was worse in ST than in patients with de novo STEMI (87.2 vs 93.7%, P = 0.02). Pts with ST had higher in-hospital MACE (11% vs 3%, p= 0.0001), MACE at 30 days (19% vs 6%, P<0.0001), this persisted up to 3 years (41% vs 12%, p <0.0001). MACE was driven by higher rates of MI (7% vs 2%, P<0.0001), TVR (14% vs 3%, p<0.0001) and death (18% vs 6%, p=0.0001). After adjusting for co-morbidities, stent thrombosis was an independent predictor of long -term adverse outcome (OR=2.1, 95% CI=1.3 -2.8, p<0.001).
Conclusion: Primary PCI for treatment of ST is less effective, and these patients are at increased risk for in-hospital and long-term mortality compared with patients undergoing primary PCI due to de novo STEMI.
- © 2011 by American Heart Association, Inc.