Early Versus Delayed Coronary Angiography After Out-of-Hospital Cardiac Arrest Without ST-Segment Elevation—A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The optimal timing of coronary angiography remains unclear following out-of-hospital cardiac arrest (OHCA) without ST elevation on electrocardiogram. The objective of this systematic review and meta-analysis was to evaluate the efficacy and safety of early angiography versus delayed angiography following OHCA without ST elevation. DATA SOURCES: The databases MEDLINE, PubMed EMBASE, and CINHAL, as well as unpublished sources from inception to March 9, 2022. STUDY SELECTION: A systematic search was performed for randomized controlled trials of adult patients after OHCA without ST elevation who were randomized to early as compared to delayed angiography. DATA EXTRACTION: Reviewers screened and abstracted data independently and in duplicate. The certainty of evidence was assessed for each outcome using the Grading Recommendations Assessment, Development and Evaluation approach. The protocol was preregistered (CRD 42021292228). DATA SYNTHESIS: Six trials were included (n = 1,590 patients). Early angiography probably has no effect on mortality (relative risk [RR] 1.04; 95% CI 0.94-1.15; moderate certainty) and may have no effect on survival with good neurologic outcome (RR 0.97; 95% CI 0.87-1.07; low certainty) or ICU length of stay (LOS) (mean difference 0.41 days fewer; 95% CI -1.3 to 0.5 d; low certainty). Early angiography has an uncertain effect on adverse events. CONCLUSIONS: In OHCA patients without ST elevation, early angiography probably has no effect on mortality and may have no effect on survival with good neurologic outcome and ICU LOS. Early angiography has an uncertain effect on adverse events.