Re: 'Treatment Outcome Trends for Non-ruptured Abdominal Aortic Aneurysms: A Nationwide Prospective Cohort Study'

We thank Shirasu et al. for their comments on our recent study. Shirasu et al. describe impressive in hospital mortality results following open surgical repair (OSR) for an intact abdominal aortic aneurysm (AAA) in Japan (2.0% down to 1.2%), using data from the National Clinical Database. Although we found similar trends using data from our nationwide mandatory verified quality registry, the peri-operative mortality in the Netherlands is higher. However, our operative mortality is comparable with other vascular registries. The difference in mortality between Japan and the Netherlands could be due to selection bias, differences in input to the database, and differences in caseload per hospital. [...]