Purpose: Screening programs and greater public awareness have increased the recognition of early abdominal aortic aneurysm (AAA) disease. No medical therapy has proven effective in limiting AAA progression, and little is known regarding the safety and efficacy of exercise training in these patients. We evaluated the safety and efficacy of up to 3 yr of training in patients with early (≤5.5 cm) AAA disease.
Methods: One hundred and forty patients with small AAAs (72 ± 8 yr) were randomized to exercise training (n = 72) or usual care (n = 68). Exercise subjects participated in a combination of in-house and home training for up to 3 yr. Cardiopulmonary exercise testing (CPX) was performed at baseline and 3, 12, 24, and 36 months. Comparisons were made for AAA expansion, safety, CPX responses, and weekly energy expenditure.
Results: The average duration of participation was 23.4 ± 9.6 months; 81% of subjects completed ≥1 year. No adverse clinical events or excessive AAA growth rates related to training occurred. Exercise subjects expended a mean 1999 ± 1030 kcal·wk−1. Increases in peak exercise time and estimated METs occurred at the 3-month and 1-, 2-, and 3-yr evaluations (P < 0.01 between groups). A significant between-group interaction occurred for V˙O2 at the ventilatory threshold (P = 0.02), and submaximal heart rate was significantly reduced among exercise subjects. Neither exercise status nor level of fitness significantly influenced rate of AAA enlargement.
Conclusions: These results support the safety and efficacy of training in patients with small AAA, a population for which few previous data are available. Despite advanced age and comorbidities, training up to 3 yr was well tolerated and sustainable in AAA patients. Training did not influence rate of AAA enlargement.
1Division of Cardiology, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA; 2Department of Vascular Surgery, Kaiser Permanente, Santa Clara, CA; and 3Department of Surgery, Stanford University, Stanford, CA
Address for correspondence: Jonathan Myers, Ph.D., VA Palo Alto Health Care System, Cardiology 111C, 3801 Miranda Ave., Palo Alto, CA 94304; E-mail: email@example.com.
Submitted for publication March 2013.
Accepted for publication June 2013.