Toward better understanding of coronary anatomy in refractory out-of-hospital cardiac arrest

Coronary features across the spectrum of out-of-hospital cardiac arrest with ST-elevation myocardial infarction (CAD-OHCA study)

AIM

We hypothesized that adult patients with out-of-hospital cardiac arrest (OHCA) and ST-elevation myocardial infarction (STEMI) requiring prolonged resuscitation have more severe coronary artery disease (CAD) than those responding rapidly, and more severe CAD than patients with STEMI without OHCA.

METHODS

Consecutive conscious and comatose OHCA patients with STEMI after reestablishment of spontaneous circulation (ROSC), and patients with refractory OHCA undergoing veno-arterial extracorporeal membrane oxygenation (E-CPR OHCA) were compared to STEMI without OHCA (STEMI no OHCA). CAD severity was assessed by a single physician blinded to the resuscitation method, time to ROSC and level of consciousness.

RESULTS

Between 2016 and 2022, 71 conscious OHCA, 157 comatose OHCA, 50 E-CPR OHCA and 101 STEMI no OHCA underwent immediate coronary angiography. Acute culprit lesion was documented less often in OHCA (88.1% vs 97%; p = 0.009) but complete occlusion was more frequent (68.8% vs 58.4%; p = 0.038) than in STEMI no OHCA. SYNTAX score was 5.6 in STEMI no OHCA, 10.2 in conscious OHCA, 13.4 in comatose OHCA and 26.8 in E-CPR OHCA (p < 0.001). There was a linear correlation between SYNTAX score and delay to ROSC/ECMO initiation (r2 = 0.61; p < 0.001). Post PCI culprit TIMI 3 flow was comparable between the groups (≥86%). SYNTAX score was among independent predictors of 5-year survival which was significantly decreased in comatose OHCA (56.1%) and E-CPR OHCA (36.0%) compared to conscious OHCA (83.1%) and STEMI no OHCA (88.1%).

CONCLUSION

Compared to STEMI no OHCA, OHCA was associated with increased incidence of acute coronary occlusion and more complex non culprit CAD which progressively increased from conscious OHCA to E-CPR OHCA. Severity of CAD was associated with increased delays to ROSC/ECMO initiation and decreased long term survival.

Coronary angiography findings in resuscitated and refractory out-of-hospital cardiac arrest: A systematic review and meta-analysis

INTRODUCTION

Coronary angiography (CAG) frequently reveals coronary artery disease (CAD) after out-of-hospital cardiac arrest (OHCA), but its use is not standardized and often reported in different subpopulations. This systematic review and meta-analysis accurately describes angiographic features in resuscitated and refractory OHCA.

METHODS

PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched up to October 31, 2022. Studies reporting coronary angiography findings after OHCA were considered eligible. The primary outcome was location and rate of coronary lesions. Coronary angiography findings with 95% confidence intervals were pooled with a meta-analysis of proportion.

RESULTS

128 studies (62,845 patients) were included. CAG, performed in 69% (63-75%) of patients, found a significant CAD in 75% (70-79%), a culprit lesion in 63% (59-66%), and a multivessel disease in 46% (41-51%). Compared to patients with return of spontaneous circulation, refractory OHCA was associated with more severe CAD due to a higher rate of left main involvement (17% [12-24%] vs 5.7% [3.1-10%]; p = 0.002) and acute occlusion of left anterior descending artery (27% [17-39%] vs 15% [13-18%]; p = 0.02). Nonshockable patients without ST-elevation were those receiving CAG less frequently, despite significant disease in 54% (31-76%). Left anterior descending artery was the most frequently involved (34% [30-39%]).

CONCLUSIONS

Patients with OHCA have a high prevalence of significant CAD caused by acute and treatable coronary lesions. Refractory OHCA was associated with more severe coronary lesions. CAD was also present in patients with nonshockable rhythm and without ST elevation. However, heterogeneity of studies and selection of patients undergoing CAG limit the certainty of findings.