Abstract 1755: The Benefit and Optimal Timing of Early Invasive Therapy in Acute Coronary Syndromes: A Meta-Analysis of Contemporary Randomized Clinical Trials
Background: The benefit and optimal timing of early invasive therapy on adverse cardiovascular outcomes is unknown.
Hypothesis: Our aim was to determine if early invasive therapy improves survival and reduces adverse cardiovascular events in the management of acute coronary syndromes. We also tested the hypothesis that very early invasive therapy (within 24 hours) would result in greater benefit than later invasive therapy (after 24 hours).
Methods: Clinical trials that randomized acute coronary syndrome patients in the era of enhanced anti-platelet therapy and coronary stents to early invasive therapy versus a more conservative approach were included for analysis.
Results: In all there were 7 trials (FRISC-II, TRUCS, TIMI-18, VINO, RITA-3, ISAR-COOL, and ICTUS) with 8,375 patients available for analysis. At a weighted mean follow-up of 2 years, the incidence of all cause mortality was 4.9% in the early invasive group, compared to 6.5% in the conservative group (RR = 0.75, 95% CI 0.63– 0.90, p = 0.001). Similarly, the incidence of non-fatal myocardial infarction was 7.6% versus 9.1% (RR = 0.83, 95% CI 0.72– 0.96, p = 0.012) and the incidence of rehospitalization for unstable angina was 19.9% versus 28.7% (RR = 0.69, 95% CI 0.65– 0.74, p < 0.0001). There were 4 studies (3,961 patients) that performed early invasive therapy within 24 hours (median time to angiography of 9.3 hours) and 3 studies (4,414 patients) that performed later invasive therapy (median time to angiography of 39 hours). When early invasive therapy was performed more than 24 hours after randomization, there was a reduction in mortality (RR = 0.73, 95% CI 0.60 – 0.89, p = 0.002), however when angiography was performed within 24 hours there was no incremental improvement in benefit (RR = 0.82, 95% CI 0.57–1.16, p = 0.26).
Conclusions: Managing acute coronary syndromes by early invasive therapy improves long term survival and reduces myocardial infarction and rehospitalization for unstable angina. There is no incremental benefit in performing very early invasive therapy compared to later (although within 48 hours) invasive therapy.