Comparison of Immediate vs Early Invasive Strategy in Patients With First Acute Non–ST‐Elevation Myocardial Infarction

Abstract

The best timing for coronary angiography (immediate vs early) in patients with acute non-ST-elevation myocardial infarction (NSTEMI) is controversial. Evaluate in NSTEMI patients the effects of an immediate compared to an early invasive strategy on microvascular damage, myocardial perfusion, and infarct size. We randomized 54 consecutive patients with first episode of NSTEMI: 27 patients (22 males, age 58.8 ± 9.4 years, group A) underwent immediate (≤6 hours) percutaneous coronary intervention (PCI) with a double bolus of eptifibatide, and 27 patients (24 males, age 59.7 ± 9.8 years, P = 0.72, group B) underwent early (7-72 hours) PCI with upstream eptifibatide. Microvascular damage was evaluated at predischarge by myocardial contrast echocardiography, and the contrast defect length was calculated. There were no significant differences in pre-PCI myocardial blush grade (MBG) (41% MBG 0 or 1 in group A vs 37% MBG 0 or 1 in group B, P = 0.78), in post-PCI MBG (7.4% MBG 0 or 1 in both groups, P = 1.00), and in contrast defect length (4.5% in group A vs 2.8% in group B, P = 0.56). However, group A showed a significant reduction in creatine kinase myocardial band isoenzyme peak (26 ± 26 ng/mL in group A vs 69 ± 79 ng/mL in group B, P = 0.01) and in troponin T peak (0.84 ± 1.2 ng/mL in group A vs 1.8 ± 2.1 ng/mL in group B, P = 0.048). In patients with NSTEMI treated with eptifibatide, immediate PCI is associated with less increase in myonecrosis markers compared with PCI within 72 hours. There were no significant differences in myocardial perfusion between the 2 strategies.