Functional Benefits of Peripheral Vascular Bypass Surgery for Patients with Intermittent Claudication

Abstract

Many patients with peripheral arterial disease (PAD) undergo peripheral bypass surgery to relieve the symptom of intermittent claudication. However, measurement of graft patency alone, assessed by change in ankle blood pres sure, may not adequately reflect the improvement in functional status following the operation. Fourteen patients with moderately severe intermittent claudica tion were evaluated before and after bypass surgery to assess changes in hemo dynamics (by resting ankle-brachial indices-ABIs), exercise performance (by a graded treadmill protocol), and community-based walking ability (by a ques tionnaire that characterizes self-reported walking speed and distance). Six weeks after surgery, resting ABIs improved in surgical patients (from 0.56 ± 0.09 to 0.93 ± 0.16, P < 0.05). Peak treadmill walking time improved from 6.2 ± 5.9 to 11.8 ± 7.1 min (90%), peak oxygen consumption from 15.5 ± 6.5 to 19.1 ± 8.5 mL/kg/min (23%), and pain-free walking time from 1.5 ± 0.4 to 6.0 5.5 min (290%). Questionnaire scores for walking distance improved by 203% and for walking speed by 130% (all P < 0.05). After twelve weeks, improve ments other than pain-free walking time were maintained. Changes in peak treadmill performance or questionnaire scores were not correlated with the ini tial ABI, changes in ABI six or twelve weeks after surgery, or the type or extent of bypass surgery. The results demonstrate that surgical treatment of PAD, indi cated for the relief of intermittent claudication, improves exercise performance and self-reported community-based walking ability. The change in functional status of the patient is an important outcome of surgery that cannot be pre dicted from routine noninvasive testing alone and should be measured directly.