ROLE OF ST–SEGMENT ELEVATION AT POST–ROSC ECG IN PATIENTS RESUSCITATED FROM OUT–OF–HOSPITAL CARDIAC ARREST

A 12–lead electrocardiogram (ECG), performed after return of spontaneous circulation (ROSC) in out–of–hospital cardiac arrest (OHCA), is essential for the identification of ST–segment elevation). The aim of the study is to investigate whether the presence of ST elevation may be a prognostic determinant in post–OHCA patients.

A total of 878 post–ROSC ECGs were collected from patients enrolled from 01/01/2015 to 12/31/2022 from the Lombardy Region Cardiac Arrest Registry (LombardiaCARe). Univariable and multivariable Cox regression models were applied to test the association between the presence of and morphology of supraST and mortality at 30 days after the event.

Among the 878 post–ROSC ECGs, 406 (46.2%) had ST elevation [49 with tombstone morphology; 26 with lambda morphology; 45 with triangular morphology; and 8 with wave morphology]. Patients with ST elevation were more frequently males (73% vs 59%, p<0.001), younger [66 years old (57–75) vs 71 (61–80), p<0.01], and with a more frequently non–defibrillating rhythm of presentation (25%vs59%, p<0.01) and an event more frequently witnessed by 118 (30% vs 21%, p=0.008). Thirty–day survival was higher in patients with ST elevation (56% vs 41%, p<0.001). Correcting for variables associated with 30–day survival (age, sex, QRS amplitude, ECG acquisition time, first rhythm of presentation), the presence of ST elevation was not significantly associated with 30–day mortality [HR: 0.67 (95% CI: 0.27–1.64); p=0.05], while the number of segments was [1.1 (95%CI 0.85–0.15), p=0.004]. No morphology was independently associated with mortality when compared with standard morphology.

The presence of ST elevation on ECG post ROSC possesses, in addition to a known diagnostic role, a prognostic role in predicting 30–day survival especially if present in more than one segment.