Determinants of Undertaking Coronary Angiography and Adverse Prognostic Predictors Among Patients Presenting With Out-of-Hospital Cardiac Arrest and a Shockable Rhythm.

Characteristics of patients presenting with out-of-hospital cardiac arrest (OHCA) selected for coronary angiography (CA) and factors predicting in-hospital mortality remain unclear. We assessed clinical characteristics associated with undertaking CA in patients presenting with OHCA and shockable rhythm (CA group). Predictors of in-hospital mortality were evaluated with multivariable analysis. Of 1,552 patients presenting with cardiac arrest between 2014 and 2018 to 2 health services in Victoria, Australia, 213 patients with OHCA and shockable rhythm were stratified according to CA status. The CA group had shorter cardiopulmonary resuscitation duration (17 vs 25 minutes) and time to return of spontaneous circulation (17 vs 26 minutes) but higher proportion of ST-elevation on electrocardiogram (48% vs 24%) (all p <0.01). In-hospital mortality was 38% (n = 81) for the overall cohort, 32% (n = 54) in the CA group, and 61% (n = 27) in the no-CA group. Predictors of in-hospital mortality included non-selection for CA (odds ratio 4.5, 95% confidence interval 1.5 to 14), adrenaline support (3.9, 1.3 to 12), arrest at home (2.7, 1.1 to 6.6), longer time to defibrillation (2.5, 1.5 to 4.2 per 5-minute increase), lower blood pH (2.1, 1.4 to 3.2 per 0.1 decrease), lower albumin (2.0, 1.2 to 3.3 per 5 g/L decrease), higher Acute Physiology and Chronic Health Evaluation II score (1.7, 1.0 to 3.0 per 5-point increase), and advanced age (1.4, 1.0 to 2.0 per 10-year increase) (all p ≤0.05). In conclusion, non-selection for CA, concomitant cardiogenic shock requiring inotropic support, poor initial resuscitation (arrest at home, longer time to defibrillation and lower pH), greater burden of co-morbidities (higher Acute Physiology and Chronic Health Evaluation II score and lower albumin), and advanced age were key adverse prognostic indicators among patients with OHCA and shockable rhythm.