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

Abstract

Background:The best timing for coronary angiography (immediate vs early) in patients with acute non-STelevation myocardial infarction (NSTEMI) is controversial. Hypothesis: Evaluate in NSTEMI patients the effects of an immediate compared to an early invasive strategy on microvascular damage, myocardial perfusion, and infarct size. Methods: 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.Results: 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). Conclusions: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. IntroductionIn patients with acute non-ST-elevation myocardial infarction (NSTEMI), an early invasive strategy with coronary angiography (CA) and subsequent revascularization through percutaneous coronary intervention (PCI) is associated with reduced rates of death and myocardial infarction (MI) in comparison with a conservative strategy. 1 Guidelines for the treatment of patients with acute coronary syndromes (ACS) recommend an early (≤72 hours) invasive strategy for patients admitted with diagnosis of NSTEMI. 2 Excluding conditions requiring emergency interventions (refractory angina, shock, and life-threatening arrhythmias), controversy remains regarding the optimal timing between hospital admission and the invasive procedure, with 2 different alternatives for the invasive approach:

Meta‐analysis of optimal timing of coronary intervention in non‐ST‐elevation acute coronary syndrome

“…After reviewing 4,611 studies from databases, 4,597 studies were excluded. Fourteen RCTs were included in the final analysis totaling 9,637 patients, 4,830 of whom underwent an early invasive strategy and 4,807 underwent a delayed invasive strategy . Our search strategy is illustrated in Figure S1.…”

“…Nevertheless, further randomized controlled trials (RCTs) have been published recently . Therefore, we performed a meta‐analysis to compare the efficacy and safety of early versus delayed invasive strategies in NSTE‐ACS …”

Role and timing of coronary intervention in non-ST-elevation myocardial infarction

“…Finally, two small singlecenter trials randomized NSTEMI patients to an early invasive versus a delayed invasive strategy. Both of the trials found better outcomes in patients treated with an early invasive strategy, although neither had defined a primary end point [81,82].…”

“…Early vs delayed ELISA (2003) [81] ISAR-COOL (2003) [82] TIMACS (2009) [80] ELISA-3 (2013) [83] Subtotal (95% CI)…”

“…In the last decade, several trials have assessed the optimal timing of coronary intervention in NSTE-ACS patients. It is useful to subdivide these into trials comparing early versus delayed intervention [77][78][79][80][81][82] and trials comparing urgent versus early intervention (Box 1) [83][84][85].…”