Abstract 20775: Optimal Timing of Invasive Strategy in Stable Non-ST-Segment Elevation Myocardial Infarction: Impact of Immediate Intervention

• Published in: Circulation (New York, N.Y.) Vol. 134; no. Suppl_1 Suppl 1; p. A20775
• Main Authors: Sim, Doo Sun, Kim, Min Chul, Jeong, Myung Ho, Ahn, Youngkeun, Kim, Young Jo, Chae, Shung Chull, Hong, Taek Jong, Seong, In Whan, Chae, Jei Keon, Kim, Chong Jin, Cho, Myeong Chan, Rha, Seung-Woon, Bae, Jang Ho, Seung, Ki Bae, Park, Seung Jung
• Format: Journal Article
• Language: English
• Published: by the American College of Cardiology Foundation and the American Heart Association, Inc 11.11.2016
• ISSN: 0009-7322; 1524-4539

BackgroundThe 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.Methods6,134 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.ResultsIn 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 (MACEcomposite 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 PCIrates 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 HR0.40, 95% CI0.22 to 0.72, p = 0.002) and death/MI (HR0.64, 95% CI0.44 to 0.93, p = 0.02 and HR0.60, 95% CI0.43 to 0.84, p = 0.003), respectively.ConclusionsImmediate 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.