Safety and Feasibility of Intravascular Lithotripsy for Treatment of Below-the-Knee Arterial Stenoses

Abstract

Purpose: To evaluate the safety and feasibility of treating calcified infrapopliteal stenoses using an intravascular lithotripsy (IVL) system.

Methods: The Disrupt BTK study was a prospective, nonrandomized, multicenter, feasibility, and safety trial that enrolled 20 patients (mean age 79.0±9.6 years; 14 men) at 3 participating sites ( ClinicalTrials.gov identifier NCT02911623). Fifteen patients had Rutherford category 5 ischemia, and all patients had moderate to severe below-the-knee arterial calcification. Patients were treated with the Shockwave Medical Peripheral IVL System and followed for 30 days. The primary safety endpoint was a composite of major adverse events through 30 days defined as death, myocardial infarction, need for emergency surgical revascularization of the target limb, or amputation of the target limb. The primary effectiveness outcome was acute reduction in the percent diameter stenosis.

Results: IVL catheter delivery was successful in 19 patients. The composite of major adverse events at 30 days was 0%. The acute reduction in percent diameter stenosis of target lesions was 46.5%. All patients achieved residual diameter stenosis ≤50%. Vascular complications were minimal with only 1 type B dissection reported and 2 stents placed. None of the subjects experienced thrombus formation, abrupt closure, distal embolization, or perforation. There were no device-related complications.

Conclusion: The early results of this pilot study demonstrated that calcified, stenotic infrapopliteal arteries can be safely and successfully treated with intravascular lithotripsy.

Keywords: arterial stenosis; below the knee; calcification; critical limb ischemia; lithoplasty; lithotripsy.

Conflict of interest statement

Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Marianne Brodmann, Andrew Holden, and Thomas Zeller received institutional grants for the Disrupt BTK study and have participated in physician advisory meetings for Shockwave Medical.

Figures

Figure 1.

Peripheral intravascular lithotripsy system.

Figure 2.

In this illustrative case (A) angiography documented a reference vessel diameter of 2.5 mm, a diameter stenosis of 95.9%, and a lesion length of 144 mm in the posterior tibial artery. (B) A 2.75-mm intravascular lithotripsy (IVL) catheter delivered 120 pulses with no pre- or postdilation. (C) Final angiography recorded a 23.6% residual stenosis and no vascular complications.