In this study, the coronary findings in 185 autopsy cases with a ruptured abdominal aortic aneurysm (AAA) from the Tokyo Medical Examiner's Office were examined and compared with those in 1,056 patients undergoing AAA repair at the University of Tokyo Hospital or Sakakibara Heart Institute (Tokyo, Japan). The number of cases with any significant coronary stenosis was significantly greater in the autopsy cases with a ruptured AAA than in the patients undergoing emergency repair of a ruptured AAA, suggesting that the low prevalence of CAD observed in patients undergoing emergency repair of a ruptured AAA was due to the survival bias before reaching hospital. In addition, we also found that significant coronary left main trunk stenosis was more frequent in CAD cases with a ruptured AAA than in those with an unruptured AAA, findings that suggest novel clinical implications. Large-scale prospective studies are warranted to confirm our findings and to clarify the pathophysiological relationship between coronary atherosclerosis and AAA status.