Association Of Timing Of Electrocardiogram Acquisition After Return Of Spontaneous Circulation With Coronary Angiography Findings In Patients With Out-Of-Hospital Cardiac Arrest

IMPORTANCE Electrocardiography (ECG) is an important tool to triage patients with out-of-hospital cardiac arrest (OHCA) after return of spontaneous circulation (ROSC). An immediate coronary angiography after ROSC is recommended only in patients with an ECG that is diagnostic of ST-segment elevation myocardial infarction (STEMI). To date, the benefit of this approach has not been demonstrated in patients with a post-ROSC ECG that is not diagnostic of STEMI.OBJECTIVE To assess whether the time from ROSC to ECG acquisition is associated with the diagnostic accuracy of ECG for STEMI.DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study (the Post-ROSC Electrocardiogram After Cardiac Arrest study) analyzed consecutive patients older than 18 years who were resuscitated from OHCA between January 1, 2015, and December 31, 2018, and were admitted to 1 of the 3 participating centers in Europe (Pavia, Italy; Lugano, Switzerland; and Vienna, Austria).EXPOSURE Only patients who underwent coronary angiography during hospitalization and who acquired a post-ROSC ECG before the angiography were enrolled. Patients with a nonmedical cause of OHCAs were excluded.MAIN OUTCOMES AND MEASURES The primary end point was false-positive ECG findings, defined as the percentage of patients with post-ROSC ECG findings that met STEMI criteria but who did not show obstructive coronary artery disease on angiography that was worthy of percutaneous coronary angioplasty.RESULTS Of 586 consecutive patients who were admitted to the 3 participating centers, 370 were included in the analysis (287 men [77.6%]; median age, 62 years [interquartile range, 53-70 years]); 121 (32.7%) were enrolled in the participating center in Pavia, Italy; 38 (10.3%) in Lugano, Switzerland; and 211 (57.0%) in Vienna, Austria. The percentage of false-positive ECG findings in the first tertile of ROSC to ECG time (<= 7 minutes) was significantly higher than that in the second (8-33 minutes) and third (>33 minutes) tertiles: 18.5% in the first tertile vs 7.2% in the second (odds ratio [OR], 0.34; 95% CI, 0.13-0.87; P = .02) and 5.8% in the third (OR, 0.27; 95% CI, 0.15-0.47; P < .001). These differences remained significant when adjusting for sex (<= 7 minutes: reference; 8-33 minutes: OR, 0.32; 95% CI, 0.12-0.85; P = .02; >33 minutes: OR, 0.26; 95% CI, 0.14-0.47; P < .001), age (<= 7 minutes: reference; 8-33 minutes: OR, 0.34; 95% CI, 0.13-0.89; P = .03; >33 minutes: OR, 0.27; 95% CI, 0.15-0.46; P < .001), number of segments with ST-elevation (<= 7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.15-0.81; P = .01; >33 minutes: OR, 0.28; 95% CI, 0.15-0.52; P < .001), QRS duration (<= 7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.14-0.87; P = .02; >33 minutes: OR, 0.27; 95% CI, 0.15-0.48; P < .001), heart rate (<= 7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.93; P = .04; >33 minutes: OR, 0.29; 95% CI, 0.15-0.55; P < .001), epinephrine administered (<= 7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.98; P = .045; >33 minutes: OR, 0.27; 95% CI, 0.16-0.48; P < .001), shockable initial rhythm (<= 7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.96; P = .04; >33 minutes: OR, 0.26; 95% CI, 0.15-0.46; P < .001), and 3 or more shocks administered (<= 7 minutes: reference; 8-33 minutes: OR, 0.36; 95% CI, 0.13-1.00; P = .05; >33 minutes: OR, 0.27; 95% CI, 0.16-0.48; P < .001) in bivariable analyses.CONCLUSIONS AND RELEVANCE This study suggests that early ECG acquisition after ROSC in patients with OHCA is associated with a higher percentage of false-positive ECG findings for STEMI. It may be reasonable to delay post-ROSC ECG by at least 8 minutes after ROSC or repeat the acquisition if the first ECG is diagnostic of STEMI and is acquired early after ROSC.