Effect of Preoperative Exercise on Postoperative Outcome in AAA Patients: Pilot Study

Basic animal research has demonstrated that exercise training can protect the myocardium from ischemia-reperfusion injury through several biological mechanisms . This effect of exercise training may be beneficial in the perioperative period when cardiac complications may arise. However, exercise induced cardioprotection is lost completely within 18 days of stopping the training program. This finding from animal research will be used to test the hypothesis that 3 days of consecutive exercise with the last bout conducted within the last 24/48 hours prior to surgery, will have a cardioprotective effect . Specifically, exercise has been shown to protect cardiac myocytes against reperfusion induced oxidative stress and mitochondria against reperfusion induced damage. This exercise mediated cardioprotection is observed in short moderate duration ischemia (i.e. 5-20 min) and moderate to severe (i.e.20-60 min) ischemic insults. The effects of exercise induced cardioprotection have only been investigated at cell level and it has not been shown whether this will translate into a reduction in postsurgical reperfusion injury and associated complications. To study this potential cardioprotective effect the investigators will aim to recruit patients who have a high risk of receiving reperfusion injury during surgery. Specifically, the investigators will recruit abdominal aortic aneurysm patients where the risk of heart complications is high. There is also currently no evidence in the published literature with regard to the effect of preoperative supervised exercise.

Patients will perform 3 consecutive days of 60 min submaximal cycling exercise at a moderate exercise intensity. During the 60 min of exercise, patients will be provided with three equally spaced 3min rest periods.

Patients will perform 3 consecutive days of 60 min submaximal cycling exercise at a moderate exercise intensity. During the 60 min of exercise, patients will be provided with three equally spaced 3min rest periods

Inclusion Criteria: Patients aged >18 years of age. Patients able to give informed consent. Able to comply with the study protocol Patients undergoing open repair for an asymptomatic perirenal and infrarenal abdominal aortic aneurysm Exclusion Criteria: Patients with severe disabling disorders limiting mobility, e.g. severe osteoarthritis Patients undergoing thoracoabdominal aneurysm surgery Patients physically unable or unwilling to undertake maximal cardiopulmonary exercise testing and the other fitness tests Patients younger than 18 years of age.

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