Background: To determine the factors influencing the prognosis of patients with abdominal aortic aneurysms (AAA), the clinical characteristics and long-term survival of 366 consecutive patients were examined and compared with those in previous Western studies.
Methods: During the period from January 1979 to December 1995, 376 patients with AAA were admitted to our hospital. Among these, 332 consecutive patients underwent elective reconstruction of infrarenal AAAs. The remaining 44 patients were not surgically treated. With use of the data from the patients who underwent AAA resection, the relationship of various risk factors, such as cardiac dysfunction, hypertension, renal dysfunction, pulmonary dysfunction, and age, to survival rate was investigated by univariate and multivariate analysis.
Results: The operative mortality rate was 0.6%. The survival of the patients who underwent the operation at 5 years was 71.0% and at 10 years 51.8%. The survival rate of the patients who were not surgically treated at 5 years was 26.0% and at 10 years 14.9%. There was a significant difference between the 2 groups. A univariate analysis was performed on each possible risk factor affecting survival rates. In relation to the survival rate of 5 and 10 years, there was no statistical significant difference between patients with or without heart disease or hypertension. By contrast, factors influencing long-term survival were associated with renal dysfunction, pulmonary dysfunction, and age at time of surgery. Multivariate analysis of risk factors affecting survival rates demonstrated that renal dysfunction, pulmonary dysfunction, and age at the time of operation were found to be significant, respectively. The main cause of the death for the long-term survival patients with AAA repair was malignancy, whereas that in the patients without repair was rupture.
Conclusions: Risk factors influencing survival after AAA repair were renal dysfunction, pulmonary dysfunction, and advanced age in Japanese patients. In addition, the main cause of death after aneurysmal resection was malignancy. These results were different from outcomes in Western patients. We need to carefully watch out for malignancy during the follow-up period after AAA resection.