Impact of off-hours admissions in STEMI-related cardiogenic shock managed with microaxial flow pump - insights from J-PVAD.

ABSTRACT

BACKGROUND: ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock (STEMI-CS) is associated with high mortality rates. Patients admitted during off-hours, specifically on weekends and at night, show higher mortality rates, which is called the "off-hours effect". The off-hours effect in patients with STEMI-CS treated with mechanical circulatory support, especially Impella, has not been fully evaluated. AIMS: We aimed to investigate whether off-hours admissions were associated with higher mortality rates in this population. METHODS: We used large-scale Japanese registry data for consecutive patients treated with Impella between February 2020 and December 2021 and compared on- and off-hours admissions. On- and off-hours were defined as the time between 800 and 1959 on weekdays and the remaining time, respectively. The Cox proportional hazards model was used to calculate the adjusted hazard ratios (aHRs) for 30-day mortality. RESULTS: Of the 1,207 STEMI patients, 566 (46.9%) patients (mean age 69 years; 107 females) with STEMI-CS treated with Impella were included. Of these, 300 (53.0%) were admitted during on-hours. During the follow-up period (median 22 days [interquartile range 13-38 days]), 112 (42.1%) and 91 (30.3%) deaths were observed among patients admitted during off- and on-hours, respectively. Off-hours admissions were independently associated with a higher risk of 30-day mortality than on-hours admissions (aHR 1.60, 95% confidence interval 1.07-2.39; p=0.02). CONCLUSIONS: Our findings indicated the persistence of the "off-hours effect" in STEMI-CS patients treated with Impella. Healthcare professionals should continue to address the disparities in cardiovascular care by improving the timely provision of evidence-based treatments and enhancing off-hours medical services.