Healthcare Utilization and Costs After Appropriate or Inappropriate Implantable Defibrillator Shocks: A Retrospective Real-World Data Study in Japan.

Background: Implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy with defibrillators (CRT-Ds) effectively prevent sudden cardiac death. However, there is a lack of detailed data on healthcare utilization and healthcare cost following ICD/CRT-D shock events in Japan. This study aimed to examine real-world data (RWD) stored in an emergency department system to clarify healthcare utilization and healthcare costs associated with ICD/CRT-D shocks in Japan. Methods and Results: This retrospective study analyzed RWD from four tertiary hospitals between January 2022 to June 2024. Among 1,807 ICD/CRT-D implanted adult patients, 84 patients (4.6%) who visited the hospital at least once following an ICD/CRT-D shock event were identified. Of these, a total of 146 ICD/CRT-D shock events were observed, with 33 patients (39.3%) experiencing multiple episodes. Of these, 122 (83.6%) were appropriate and 24 (16.4%) were inappropriate. Hospitalization was required in 55 (37.7%) cases. Appropriate shocks were associated with longer hospital stays (24.6 ± 29.3 vs. 12.5 ± 4.2 days) and higher costs (1,123,531 ± 2,195,483 JPY vs. 67,091 ± 131,282 JPY) than inappropriate shocks. Conclusion: In this multicenter retrospective study using real-world data in Japan, we investigated the healthcare utilization and costs associated with ICD/CRT-D shock events. Our findings provide valuable insight into post-shock care in daily practice and highlight the need for optimized management strategies to improve care delivery and resource use in the Japanese clinical setting.