Timing of Coronary Invasive Strategy in Non-ST-Segment Elevation Acute Coronary Syndromes and Clinical Outcomes: An Updated Meta-Analysis

Abstract

Objectives: The aim of this study was to compare an early versus a delayed invasive strategy in non-ST-segment elevation acute coronary syndromes by performing a meta-analysis of all available randomized controlled clinical trials.

Background: An invasive approach is recommended to prevent death and myocardial infarction in non-ST-segment elevation acute coronary syndromes. However, the timing of angiography and the subsequent intervention, when required, remains controversial.

Methods: A previous meta-analysis of 7 randomized clinical trials comparing early and delayed invasive strategies in non-ST-segment elevation acute coronary syndromes with 3 new randomized clinical trials identified in a search of the published research (n = 10 trials, n = 6,397 patients) was updated.

Results: The median time between randomization and angiography ranged from 0.5 to 14.0 h in the early group and from 18.3 to 86.0 h in the delayed group. There was no difference in the primary endpoint of mortality (4% vs. 4.7%; random-effects odds ratio [OR]: 0.85; 95% confidence interval [CI]: 0.67 to 1.09; p = 0.20; I² = 0%). The rate of myocardial infarction was also similar (6.7% vs. 7.7%; random-effects OR: 0.88; 95% CI: 0.53 to 1.45; p = 0.62; I² = 77.5%). An early strategy was associated with a reduction in recurrent ischemia or refractory angina (3.8% vs. 5.8%; random-effects OR: 0.54; 95% CI: 0.40 to 0.74; p < 0.01; I² = 28%) and a shorter in-hospital stay (median 112 h [interquartile range: 61 to 158 h] vs. 168 h [interquartile range: 90.3 to 192 h]; random-effects standardized mean difference -0.40; 95% CI: -0.59 to -0.21; p < 0.01; I² = 79%). Major bleeding was similar in the 2 groups (3.9% vs. 4.2%; random-effects OR: 0.94; 95% CI: 0.73 to 1.22; p = 0.64; I² = 0%).

Conclusions: An early invasive strategy does not reduce the risk for death or myocardial infarction compared with a delayed strategy. Recurrent ischemia and length of stay were significantly reduced with an early invasive strategy.

Keywords: NSTE-ACS; angiography; invasive; mortality; percutaneous coronary intervention; timing.