Abstract Body: Backgrounds: Recent advances in treatment have improved outcomes in patients with cerebrovascular accidents (CVA). Out-of-hospital cardiac arrest (OHCA) secondary to CVA is relatively uncommon, and data in this clinical scenario are scarce. In this study, we aimed to evaluate temporal trends and outcomes of OHCA with and without CVA.

Methods: Using a nationwide registry database from 2005 to 2022 in Japan, a cohort of 2,070,743 patients with OHCA were included in the present study and divided into two groups according to the presence or absence of CVA as an etiology of OHCA. Major endpoints of interest included prehospital return of spontaneous circulation (ROSC) and overall and neurologically favorable (cerebral performance category score of 1 or 2) survival at 1 month. Temporal trends between the CVA and non-CVA groups were also evaluated.

Results: Of the 2,070,743 patients, 70,419 (3.4%) had CVA as an etiology of OHCA. In the non-CVA group, the major etiologies were cardiac causes (59.9%), trauma (11.8%), and malignancy (6.7%). As compared to the non-CVA group, patients in the CVA group were younger and had a significantly lower proportion of initial shockable rhythm. Although the probability of prehospital ROSC was higher, 1-month overall and neurologically favorable survival rates were significantly lower in the CVA group than in the non-CVA group (Table). The probability of ROSC has increased in both CVA and non-CVA groups from 2005 to 2022, while overall and neurologically favorable survival have stagnated in both groups during the study period (Figure). In multivariable analysis, a significant interaction between group (CVA vs. non-CVA) and year was observed for ROSC (interaction term: odds ratio [OR] 13.81, 95% confidence interval [CI] 1.02–1.03; P < 0.0001). This association was markedly attenuated for 1-month survival (OR 2.55, 95% CI 1.00–1.02; P = 0.011), and no significant difference was found in neurologically favorable survival trends between the groups (OR 1.85, 95% CI 0.99–1.02; P = 0.064).

Conclusions: In this nationwide registry study in Japan, CVA-related OHCA was uncommon, with a proportion of 3.4%. Although the probability of prehospital ROSC was twofold higher, overall and neurologically favorable survival rates were lower in the CVA group than in the non-CVA group. The substantial improvement in ROSC was observed in the CVA group during the study period, which was not translated into better clinical outcomes.