Shockwave therapy in patients with peripheral artery disease.

Introduction: Previous studies support the fact that extracorporeal shockwave (SW) induces angiogenesis and improves symptoms in patients affected by limb ischemia. The aim of this study was to evaluate the effects of SW therapy in patients with peripheral artery disease (PAD).
Methods: Twenty-two patients were enrolled in this study and were randomly assigned into two groups: SW treatment (12 patients, 67 ± 9 years) and control (10 patients, 68 ± 12 years). The inclusion criteria were the following: age over 40 years, PAD diagnosis, optimal medical therapy, and ankle-brachial index less than 0.9. SW therapy was administered using the Minilith® SL1 litotriptor with an ultrasound guide able to detect the target area using a B-mode technique and a 7.5 MHz convex probe emitting 2,000 impulses with an energy flux density of 0.03 mJ/mm(2).
Results: The variation in the degree of stenosis before and after treatment was statistically significant between the groups (-9% ± -10% vs. 0% ± 0%; P = 0.001). In addition, a significantly higher number of treated patients than controls showed a reduction in the Fontaine stage (12 [63%] vs. 0 [0%]; P < 0.001). This result was confirmed by analyzing the difference in patients' pain-free walking distance before and after SW therapy (76 ± 46 m vs. 0 ± 0 m for treated patients vs. controls; P < 0.001) and the difference in pain severity (measured on a pain scale; -1.4 ± 0.5 in the treated patients vs. -0.2 ± 0.4 in the controls; P < 0.001).
Conclusion: On the basis of these results the authors hypothesized a direct effect of SW on the ultrastructural composition of the vessel walls, inducing a reduction in artery stenosis. These data support the application of SW therapy as a new medical tool to improve the natural clinical course of PAD.