First Database Comparison Between the United States and Japan: Coronary Artery Bypass Grafting

Background: International collaboration has an interest in health care quality evaluation. We compared characteristics and surgical outcomes between Asian patients in the United States and Japanese patients who undergo adult cardiac surgery. Methods: Using the Japan Adult Cardiovascular Surgery Database (JCVSD) and The Society of Thoracic Surgeons (STS) National Database, we compared Asian patients undergoing isolated coronary artery bypass graft surgery between 2013 and 2016 in Japan and the United States. The STS had 16,903 Asian patients among 573,823 patients of all races undergoing isolated coronary artery bypass graft surgery (2.95%); the JCVSD had 55,570 patients, almost all of whom are Japanese. Descriptive statistics were analyzed independently, then the data were aggregated for comparison. Results: The JCVSD patients were older (69 vs 65 years) with a smaller body surface area (1.65 m² vs 1.81 m²) and body mass index (24 kg/m² vs 26 kg/m²). The proportion of males (79% vs 78%), prevalence of chronic lung disease (82% vs 86%), and diabetes mellitus (54% vs 60%) were similar. The JCVSD had higher prevalence of renal disease requiring dialysis (11% vs 6%). The numbers of anastomoses were similar (3.1 vs 3.3); off-pump procedures and the usage of right internal mammary artery were more prevalent (60% vs 15% and 38% vs 7%, respectively) in the JCVSD. The unadjusted operative mortality was 2.7% in the JCVSD and 2.1% in the STS database. Conclusions: Comparisons of coronary artery bypass graft surgery characteristics and outcomes were conducted between the STS National Database and the JCVSD to illustrate the value of international collaboration on adult cardiac surgery databases.