Extracorporeal shock wave therapy improves the walking ability of patients with peripheral artery disease and intermittent claudication

Background: Despite the recent advances in bypass surgery and catheter interventional therapy for peripheral artery disease (PAD), the long-term outcome of revascularization therapy for infrapopliteal lesions remains unsatisfactory. We have previously demonstrated that low-energy extracorporeal shock wave (SW) therapy effectively induces neovascularization through upregulation of angiogenic factors and improves myocardial ischemia in pigs and humans and in hindlimb ischemia in rabbits. In this study, we thus examined whether our SW therapy also improves the walking ability of patients with PAD and intermittent claudication. Methods and Results: We treated 12 patients (19 limbs) in Fontaine II stage (males/females, 10/2; 60-86 years old) with low-energy SW therapy to their ischemic calf muscle 3 times/week for 3 consecutive weeks. After 24 weeks, the pain and distance subscale scores of the walking impairment questionnaire were significantly improved (33±25 vs. 64±26, 27±16 vs. 64±23, respectively, both P<0.01). Maximum walking distance was also significantly improved at 4 weeks (151±37% from baseline, P<0.01) and was maintained at 24 weeks (180±74% from baseline, P<0.01). Moreover, the recovery time of the tissue oxygenation index in the calf muscle during a treadmill test, which reflects local O ₂ supply, was significantly shortened (295±222 s vs. 146±137 s, P<0.01). Importantly, no adverse effects were noted. Conclusions: Non-invasive SW therapy improves the walking ability of PAD patients.