Impact of initial rhythm, rhythm at hospital admission and cause of arrest on the outcome of extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest.
The American journal of emergency medicine · 2025-09-18 · Observational study
Abstract
OBJECTIVES: The use of extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA) is increasing, although including patients with non-shockable rhythms remains controversial and data addressing the influence of rhythm remains scarce. This study aimed to assess the impact of initial rhythm, its conversion, and the underlying cause of arrest on ECPR outcomes in a real-life patient cohort. METHODS: A cohort of 281 consecutive patients undergoing ECPR for OHCA between 2016 and 2023 was retrospectively stratified based on initial and admission rhythm as well as cause of arrest. Outcomes were survival to discharge and favorable neurological function (cerebral performance category ≤2). RESULTS: An initial shockable rhythm was associated with higher survival (23.9 % vs. 7.4 %, p < 0.001) and better neurological outcome (17 % vs. 4.1 %, p < 0.001). In 45 % of cases, shockable rhythm persisted upon admission, while in 38 % converted to pulseless electrical activity, which did not impact outcomes (p = 0.32). Within the subgroup of patients with an initial non-shockable rhythm, those with initial PEA appeared to have a more favorable prognosis, as the presence of asystole at any point was associated with poorer outcomes. Notably, in cases where OHCA was caused by pulmonary embolism, survival with favorable neurological outcome was higher compared to other causes within the initial PEA subgroup. CONCLUSIONS: While routine ECPR in initial non-shockable rhythm cannot recommended, selected patients, such as those with pulmonary embolism, may benefit. Asystole at any time is associated with a poor prognosis. Detailed contemplation of pre-hospital rhythm and its dynamic changes might be reasonable.