Background: There are few data verifying the utility of the CHADS-P2A2RC score in comparison with the CHADS2 score for estimating net adverse clinical events (NACE) in real-world settings. Methods: We performed analysis for a total of 3,985 chronic coronary syndrome (CCS) patients without atrial fibrillation (AF) who underwent percutaneous coronary intervention (PCI) between April 2013 and March 2019 for whom information was obtained from the CLIDAS (Clinical Deep Data Accumulation System)-PCI database. The primary endpoint was NACE defined as the composite of 3-point major adverse cardiovascular events (3P-MACE) (cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke) and GUSTO moderate/severe bleeding events. Results: Kaplan-Meier analysis showed that both the CHADS-P2A2RC and CHADS2 scores stratified the risks. The incidences of NACE were stratified well by the very-high-risk category, which was uniquely defined as a CHADS-P2A2RC score of ≥6 (hazard ratio: 2.38, 95% CI=1.91-2.97, p-value <0.001). The area under the curve (AUC) in estimating NACE within 3 years was higher when the CHADS-P2A2RC score was used than when the CHADS2 score was used (0.67 vs. 0.62, p=0.003). This was mainly due to the accuracy in estimating bleeding events (0.66 vs. 0.60, p=0.006). Conclusions: The accuracy in estimating NACE after PCI for CCS patients without AF was higher when the CHADS-P2A2RC score was used than when the CHADS2 score was used, mainly due to the accuracy in predicting bleeding risk. Higher incidences of endpoints were well-stratified by a very-high-risk category defined as a CHADS-P2A2RC score of ≥6.

DF has received research funding from BIOTRONIK Japan; honoraria from Novartis Pharma, Otsuka Pharmaceutical, and Kowa. TM has received lecture fees from Abbott Medical, Bayer, and MSD; research funding from Amgen, Bayer, and Kowa. TKabutoya has received scholarship funding from Abbott Medical. YI has received honoraria from Daiichi Sankyo, and Toa Eiyo. KK has received a research grant from Otsuka Pharmaceutical, Sanwa Kagaku Kenkyusho, Daiichi Sankyo, MSD, Astellas Pharma, Eisai, Taisho Pharmaceutical, Sumitomo Dainippon Pharma, Takeda Pharmaceutical, Mitsubishi Tanabe Pharma, Teijin Pharma, Boehringer Ingelheim Japan, Bristol-Myers Squibb, and Mochida Pharmaceutical; consulting fees from Kyowa Kirin, Sanwa Kagaku Kenkyusho, Mochida Pharmaceutical; honoraria from Otsuka Pharmaceutical, Daiichi Sankyo, Novartis Pharma, Mylan EPD; participation in Advisory Board of Daiichi Sankyo, and Novartis Pharma. AK has received honoraria from AstraZeneca, Eli Lilly, and Sumitomo Pharma. YMizuno has received research grants and consulting fees from Bayer. YMiyamoto has received research funds from Kowa, Tokyo Marine and Nichido Fire Insurance, Fujitsu, Softbank, Saraya, and Meiji Yasuda Life Insurance. KT received research grants from PPD-Shin Nippon Biomedical Laboratories and Alexion Pharmaceuticals; scholarship funds from Abbott Medical, Bayer, Boehringer Ingelheim, Daiichi Sankyo, ITI, Ono Pharmaceutical, Otsuka Pharmaceutical, and Takeda Pharmaceutical; affiliation with the endowed department from Abbott Medical, Boston Scientific, Cardinal Health, Fides-ONE, Fukuda Denshi, GM Medical, ITI, Japan Lifeline, Kaneka Medix, Medical Appliance, Medtronic, Nipro, and Terumo; honoraria from Abbott Medical, Amgen, AstraZeneca, Bayer, Daiichi Sankyo, Medtronic, Kowa, Novartis Pharma, Otsuka Pharmaceutical, Pfizer, and Janssen Pharmaceutical. HS reports stock or stock options in Precision. HF has received scholarship funds from Abbott Vascular, speaking honoraria from Novartis and Otsuka Pharmaceutical, and served as a consultant for Mehergen Group Holdings. RN has received honoraria from Kowa, Takeda Pharmaceutical, Tanabe-Mitsubishi Pharmaceutical, and Boehringer-Ingelheim. All other authors have no conflicts of interest to declare.

This work was supported by the Cross-ministerial Strategic Innovation Promotion Program (SIP) on ?Integrated Health Care System? Grant Number JPJ012425. In addition, the authors thank the Kowa Company for funding the development of CLIDAS-PCI.

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