Background: Because direct application of low-energy shock waves induces angiogenesis, we investigated the safety and efficacy of this new therapy to develop a noninvasive method of repeatable therapeutic angiogenesis for treating peripheral arterial disease (PAD).
Subjects and methods: The subjects were 10 patients who had symptomatic PAD and limited ischemia in a below-the-knee artery. Low-energy shock waves were directly applied to the calf muscles 6 times every other day. Intracorporeal changes were evaluated with ultrasonography to determine adverse effects of therapy. To assess blood flow of the microcirculation, transcutaneous oxygen tension (TcPO2), skin perfusion pressure (SPP), and (99m)technetium-tetrofosmin ((99m)Tc-TF) scintigraphy were performed before and after therapy. The TcPO2 was measured while subjects inhaled pure oxygen (maximum TcPO2). The (99m)Tc-TF perfusion index was determined as a ratio of uptake in muscle to that in the brain (control) for quantitative analysis.
Results: No adverse effects were noted in any patient. Maximum TcPO2 values increased significantly on the calf (57.3±28.4 to 71.0±14.5 mm Hg, p=0.044) and the dorsum of the foot (52.2±21.8 to 76.1±17.9 mm Hg, p=0.012). The SPP tended to increase after therapy on the dorsum and plantar surfaces of the foot, but the differences were not significant. The (99m)Tc-TF perfusion index in the foot significantly increased (0.48±0.09 to 0.61±0.12, p=0.0013), but that in the leg did not change.
Conclusion: We have demonstrated that low-energy shock wave therapy is safe and can restore blood flow in the microcirculation in patients with symptomatic PAD.