Validation of the BCIS-CHIP score for predicting long-term outcomes in a Japanese population

Abstract Background The British Cardiovascular Intervention Society (BCIS) CHIP score was originally developed to assess short-term in-hospital outcomes in complex high-risk percutaneous coronary intervention (CHIP) patients. Recently, a North American study validated its predictive value for long-term major adverse cardiovascular and cerebrovascular events (MACCE). However, its performance in Japanese populations remains unclear. Given that Japanese patients have been reported to have a lower incidence of MACCE than Western populations, the applicability of the CHIP score to this lower-risk population remains uncertain. Purpose This study aimed to assess the predictive ability of the BCIS-CHIP score for long-term MACCE in a Japanese PCI cohort. Methods This retrospective study included consecutive patients who underwent PCI at our hospital between February 2021 and May 2024. Patients were stratified into four groups according to their BCIS-CHIP score (0, 1-2, 3-4, and ≥5). The primary outcome was MACCE, defined as a composite of all-cause death, myocardial infarction, and stroke. Cox proportional hazards regression models were used to estimate the hazard ratios (HRs) for the primary outcome. The predictive ability of the BCIS-CHIP score was assessed using the area under the receiver operating characteristic curve (AUC). Results Among 623 patients (median age 72 years IQR 65-80, 82% male), MACCE occurred in 1.4% of those with a CHIP score of 0 (reference), 4.6% with a score of 1-2 (HR: 2.98; 95% CI: 0.68-13.1, P=0.15), 11.5% with a score of 3-4 (HR: 7.13; 95% CI: 1.64-31.0, P=0.009), and 13.3% with a score of ≥5 (HR: 11.4; 95% CI: 2.07-62.4, P=0.005). The BCIS-CHIP score demonstrated moderate predictive ability for MACCE, with an AUC of 0.73 (95% CI: 0.66-0.81), showing a clear trend of increasing risk across categories. Conclusion Despite the lower incidence of MACCE, the BCIS-CHIP score effectively predicted long-term MACCE risk in this Japanese cohort.BCIS-CHIP Score Survival free from MACCE