Post-ROsc ecG pREdictS Survival after out-of hospital cardiac arrest: validation of the PROGRESS score

Abstract Background Prognostication is crucial for patients with an out-of-hospital cardiac arrest (OHCA) both during resuscitation and after return of spontaneous circulation (ROSC) and early prognostication is still a challenge. At this regard, we proposed the PROGRESS score: a post-ROSC 12-lead ECG features’-based score to predict 30-day survival. Purpose The aim of the present study is to validate the PROGRESS score on a larger population of post-OHCA patients and to test its performance even after correction for patients’ and events’ characteristics, contained in the UB-ROSC score, could increase its discrimination ability. Methods Cardiac arrest cases were retrieved from the Lombardy Cardiac Arrest Registry (LombardiaCARe) from January 2015 to December 2022. We considered only patients with a post-ROSC 12-lead ECG and all the variables for UB-ROSC calculation available. The PROGRESS score considers age, sex, number of segments with ST elevation, QRS width, and Brugada pattern and from 0 to 26 identifies three categories of risk of death at 30 days (low: 0-4; intermediate: 5-7; high: 8-26). The UB-ROSC score considers age, aetiology, location, witnessed OHCA, bystander cardiopulmonary resuscitation (CPR), emergency medical service (EMS) arrival time and type of presenting rhythm. The performance of the PROGRESS score, in terms of discriminatory power of calibration, was tested both alone and after correction for UB-ROSC score. Results We considered 940 OHCAs of whom 63.9% were males with a median age of 70 [59.5-79]. 30-day survival was 37.9%, 63.1% and 64.5% in high, intermediate, and low risk groups respectively. PROGRESS score was shown to discriminate high-risk patients from low-risk ones [HR 1.97 (95% CI 1.42-2.73), p-value <0.001], (Harrel-C= 0.58). After correction for UB-ROSC score both calibration and discrimination improved (Harrel-C = 0.70). Conclusions The PROGRESS score was confirmed to predict the risk of death at 30 days in patients resuscitated from an OHCA and its discriminatory power was increased by correction for the UB-ROSC score. The use of this two scores in the field allows risk stratification during resuscitation manoeuvres and in post-ROSC care, which is essential to guide resource allocation.