Potential return of spontaneous circulation in Japanese out-of-hospital cardiac arrest patients with pseudo-pulseless electrical activity: a post hoc analysis of a prospective multicentric study.

INTRODUCTION: As of yet, there are few studies of Asian patients with pseudo-pulseless electrical activity (PEA). Japanese patients with out-of-hospital cardiac arrest (OHCA) tend to be elderly, experience cardiac arrest while at home, and present with severe illness. The present study evaluated the prognostic implications of pseudo-PEA in a Japanese cohort with a high risk of OHCA.

METHODS: The present study is a post hoc analysis of SOS-KANTO 2017, a prospective, multicentric study which included OHCA patients with PEA on hospital arrival who underwent echocardiographic assessment during resuscitation. The patients were categorized into a pseudo-PEA and a true PEA group. The primary outcome was the return of spontaneous circulation (ROSC). The secondary outcomes included survival to hospital admission, 30-day survival, and a favorable neurological status at discharge. Logistic regression was performed with cardiac activity as the primary predictor after adjusting for covariates.

RESULTS: Of 894 eligible patients, 345 had pseudo-PEA, and 549 had true PEA. In total, 49.3% achieved ROSC. The pseudo-PEA group had a significantly higher rate of ROSC (87.2% vs. 25.5%; p < 0.01). On multivariable logistic regression, the pseudo-PEA group was independently associated with a high ROSC rate (odds ratio [OR]: 22.1; 95% confidence interval [CI]: 14.2-34.3), survival to hospital admission (OR: 17.8; 95% CI: 11.2-28.2), 30-day survival (OR: 51.9; 95% CI: 7.33-367), and favorable neurological outcome at discharge (OR: 14.3; 95% CI: 1.62-125).

CONCLUSION: Pseudo-PEA may be associated with a higher rate of ROSC and favorable, short and middle-term outcomes in Japanese patients with OHCA. Early echocardiographic assessment of cardiac activity may help prognostication and guide resuscitation even in high-risk populations.