Mørk SR, Stengaard C, Linde L, et al. - Researchers undertook this retrospective, observational cohort study to report the gradual implementation, survival as well as adherence to the national consensus regarding use of mechanical circulatory support (MCS) for out-of-hospital cardiac arrest (OHCA) in Denmark, as well as to explore factors related to outcome. There were 259 patients who took part in this analysis. Thirty-day survival was noted to be 26%. A 30-day survival rate of 30% was obtained with strict adherence to the national consensus vs 22% in patients violating one or more criteria. Factors related to elevated risk of 30-day mortality, on logistic regression, included: asystole, pulseless electrical activity, initial pH < 6.8 and lactate levels > 15 mmol/L. Overall, this Danish population of patients managed with MCS for OHCA was found to have a high survival rate with a good neurological outcome. Higher survival rates may be obtained with stringent patient selection for MCS but it potentially withholds life-saving treatment in a significant proportion of survivors.