Abstract 20775: Optimal Timing of Invasive Strategy in Stable Non-ST-Segment Elevation Myocardial Infarction: Impact of Immediate Intervention
Background: The optimal timing of intervention in non-ST-elevation myocardial infarction (NSTEMI) remains controversial. We sought to assess impact of immediate percutaneous coronary intervention (PCI) for NSTEMI.
Methods: 6,134 NSTEMI patients undergoing PCI from the Korea Acute Myocardial Infarction Registry were divided into group 1 (immediate PCI within 4 h, n = 1,132) and group 2 (deferred PCI after 4 h, n = 5,002). Patients with recurrent or refractory ischemia, systolic blood pressure <90 mmHg, Killip class ≥3, ventricular arrhythmia, cardiac arrest, or mechanical complications were excluded. Propensity-matched 12-month clinical outcome was compared between the groups and according to time to PCI.
Results: In all patients and propensity-matched cohort (n = 1,131 in each group), group 1 had higher peak troponin level, higher rate of pre-PCI Thrombolysis In Myocardial Infarction (TIMI) grade 0 or 1, higher use of glycoprotein IIb/IIIa inhibitor, and lower use of unfractionated heparin and nitrates. In all patients, 12-month rates of MI and death/MI were higher in group 1. No differences were observed in 12-month death and major adverse cardiac events (MACE: composite of death, MI, target-vessel revascularization, and coronary artery bypass graft surgery). In the propensity-matched cohort, no significant differences were observed in 12-month rates of death, MI, death/MI or MACE. However, group 1 had less major bleeding (0.8% vs. 3.0%, p = 0.024) and shorter hospital stay. In the propensity-matched cohort, the effect of PCI on 12-month outcome showed a U-shaped relationship with time to PCI: rates of MI and death/MI (≤4 h, 4-12 h, 12-24 h, 24-72 h, >72 h after arrival) were 2.7%, 1.3%, 1.1%, 1.9%, 2.2% and 6.5%, 4.2%, 3.9%, 5.2%, 6.1%, respectively. PCI 4-12 h and 12-24 h after arrival was associated with lower risk of 12-month MI (hazard ratio [HR]: 0.49, 95% confidence interval [CI]: 0.25 to 0.93, p = 0.03 and HR: 0.40, 95% CI: 0.22 to 0.72, p = 0.002) and death/MI (HR: 0.64, 95% CI: 0.44 to 0.93, p = 0.02 and HR: 0.60, 95% CI: 0.43 to 0.84, p = 0.003), respectively.
Conclusions: Immediate PCI for stable NSTEMI did not confer an advantage with respect to hard clinical endpoints at 12 months. PCI within 4-24 h after arrival was associated with lower risk of adverse events.
Author Disclosures: D. Sim: None. M. Kim: None. M. Jeong: None. Y. Ahn: None. Y. Kim: None. S. Chae: None. T. Hong: None. I. Seong: None. J. Chae: None. C. Kim: None. C. Kim: None. M. Cho: None. S. Rha: None. J. Bae: None. K. Seung: None. S. Park: None.
- © 2016 by American Heart Association, Inc.