Coronary angiography findings in patients with shock-resistant ventricular fibrillation cardiac arrest

Introduction: Shock-resistant ventricular fibrillation (VF) poses a therapeutic challenge during out-of-hospital cardiac arrest (OHCA). For these patients, new treatment strategies are under active investigation, yet underlying trigger(s) and substrate(s) have been poorly characterised, and evidence on coronary angiography (CAG) data is often limited to studies without a control group.

Methods: In our OHCA-registry, we studied CAG-findings in OHCA-patients with VF who underwent CAG after hospital arrival. We compared baseline demographics, arrest characteristics, CAG-findings and outcomes between patients with VF that was shock-resistant (defined as >3 shocks) or not shock-resistant (≤3 shocks).

Results: Baseline demographics, arrest location, bystander resuscitation and AED-use did not differ between 105 patients with and 196 patients without shock-resistant VF. Shock-resistant VF-patients required more shocks, with higher proportions endotracheal intubation, mechanical CPR, amiodaron and epinephrine. In both groups, significant coronary artery disease (≥1 stenosis >70%) was highly prevalent (78% vs. 77%, p = 0.76). Acute coronary occlusions (ACOs) were more prevalent in shock-resistant VF-patients (41% vs. 26%, p = 0.006). Chronic total occlusions did not differ between groups (29% vs. 33%, p = 0.47). There was an association between increasing numbers of shocks and a higher likelihood of ACO. Shock-resistant VF-patients had lower proportions 24-h survival (75% vs. 93%, p < 0.001) and survival to discharge (61% vs. 78%, p = 0.002).

Conclusion: In this cohort of OHCA-patients with VF and CAG after transport, acute coronary occlusions were more prevalent in patients with shock-resistant VF compared to VF that was not shock-resistant, and their clinical outcome was worse. Confirmative studies are warranted for this potentially reversible therapeutic target.