Background: Patients admitted to the hospital after successful resuscitation from sudden cardiac death (SCD) are treated with therapeutic hypothermia (TH) to facilitate brain preservation. The prognostic significance of J (Osborn) waves (JOW) in the 12 leads electrocardiogram in this setting has not been elucidated as yet.

Objectives: To ascertain retrospectively the prognostic significance of JOW recorded during TH in SCD survivors.

Methods: The study comprised 55 consecutive patients who underwent TH. All patients achieved a core temperature of 33°C at the time of electrocardiogram analysis. We compared 33 patients with JOW to 22 patients without JOW. The endpoints were in-hospital, long-term all-cause mortality, and irreversible anoxic brain injury (IABI).

Results: Patients with JOW compared to patients without JOW were younger (55.1 ± 11.6 vs. 64.5 ± 11.7 years, respectively, P < 0.006), with a lower incidence of hypertension (52% vs. 86%, P < 0.007), diabetes mellitus (15% vs. 50%, P < 0.005), and congestive heart failure (15% vs. 45%, P < 0.013). In-hospital and long-term mortality were significantly higher in patients without JOW (86% vs. 21%, 91% vs. 24%, respectively, P < 0.000001). Among patients without JOW who survived hospitalization, 66.7% presented with IABI versus 7.7% of the patients with JOW (P < 0.0001). In multivariate analysis, the absence of JOW was a significant predictor for poor prognosis.

Conclusions: The absence of J (Osborn) waves on electrocardiograms obtained during TH is associated with poor prognosis among SCD survivors