Prognostic value of the pre-procedural six minute walk test in patients undergoing open abdominal aortic aneurysm repair – A prospective observational study

Abstract

Objective: Open surgery for aortic aneurysm is associated with significant morbidity and mortality. Preoperative functional status is one of the key predictors of adverse outcomes in the postoperative period. This study investigated the role of 6-min walk test (6MWT) in predicting the outcomes after open surgery in abdominal aortic aneurysm (AAA). Methods: A prospective cohort study was conducted in patients scheduled to undergo open repair of AAA. The preoperative 6-min walk distance (6MWD) was calculated for patients, followed by postoperative monitoring of all patients who underwent surgery. Walking performance was classified with 300 m as a cutoff, and patients were divided into two groups with 6MWD- <300 m and >300 m. The results of 6MWT were analyzed with respect to cardiopulmonary complications, intensive care unit (ICU) stay, ventilatory or inotropic support, length of hospital stay, and mortality. Results: A total of 52 patients were included in the study, and 49 patients were able to complete the 6MWT. The patients with <300 m 6MWD had a longer stay in the ICU and an increased duration of ventilatory and inotropic support (P < 0.001). The <300-m group had an increased incidence of cardiopulmonary complications (47%, P = 0.001). The <300-m group had a higher duration of hospital stay (10.6 vs. 8.4 days; P = 0.01). All the patients who died in the perioperative period had a 6MWD <300 m (n = 3, P = 0.03). The 6MWD was the only strong predictor of adverse outcomes in the cohort. Conclusion: 6MWT can be safely performed in patients with AAA. A low walking distance correlates directly with increased perioperative morbidity and length of hospital stay. A distance of <300 m in patients with aortic aneurysm is predictive of perioperative morbidity and mortality.