Timing of Coronary Angiography in Patients Following Out-of-Hospital Cardiac Arrest Without ST-Segment Elevation: A Systematic Review and Meta-Analysis of Randomized Trials

Abstract

IntroductionOut-of-hospital cardiac arrest (OHCA) has a poor prognosis. The timing and role of early coronary angiography (CAG) in OHCA patients without ST elevation remains unclear. ObjectiveWe performed a meta-analysis of randomized controlled trials (RCTs) that compared early CAG to delayed CAG in OHCA patients without ST elevation. MethodsWe searched PubMed, Cochrane, and ClinicalTrials.gov databases (from inception to September 2021) for studies comparing early CAG to delayed CAG in OHCA patients without ST elevation. We used a random-effect model to calculate relative ratio (RR) with 95% confidence interval (CI). The primary outcome was all-cause mortality at 30 days. Secondary outcomes included neurological status with cerebral performance category ≤2 (CPC) and the rate of percutaneous coronary intervention (PCI) following CAG. ResultsA total of 6 RCTs including 1822 patients, of whom 895 underwent early CAG, and 927 underwent delayed CAG, were included in this meta-analysis. There was no statistically significant difference between the 2 groups in terms of 30-day all-cause mortality (Relative risk [RR] 1.06; 95%CI 0.94–1.20; P = 0.32; I2 = 13%), neurological status (CPC ≤2) (RR 1.01; 95%CI 0.90–1.13; P = 0.85, I2 = 37%), and rates of PCI following CAG (RR 1.08; 95%CI 0.84–1.39; P = 0.56; I2 = 49%). ConclusionIn patients suffering OHCA without ST-elevation, early CAG is not associated with reduced 30-day mortality when compared to patients who underwent delayed CAG. Given our meta-analysis results including multiple trials that have not shown a benefit, it is likely that updated guidelines will not support early angiography in patients suffering OHCA without ST-elevation.