Intravascular Lithotripsy for Treatment of Calcified Infrapopliteal Lesions: Results from the Disrupt PAD III Observational Study

Abstract

Purpose: To evaluate the safety and effectiveness of the Shockwave S4 intravascular lithotripsy (IVL) catheter in an “all-comers” cohort of patients with calcified infrapopliteal lesions. Materials and Methods: The Disrupt PAD III Observational Study (NCT02923193) is a prospective, nonrandomized, multicenter single-arm study designed to assess the “real-world” acute safety and effectiveness of the Shockwave Peripheral IVL System for the treatment of de novo calcified, stenotic peripheral arteries. Patients were eligible for enrollment if they had claudication or critical limb ischemia (CLI) and at least moderate calcification as assessed by angiography. This subanalysis includes consecutive patients enrolled with angiographic core lab-assessed treatment of infrapopliteal arteries using the Shockwave S4 IVL catheter. Results From July 2018 to August 2020, 101 patients with 114 calcified infrapopliteal arteries treated with the S4 IVL catheter were enrolled at 15 sites in 3 countries. CLI was present in 69.3% of patients. The anterior tibial and tiboperoneal trunk were the most commonly treated vessels with an overall mean reference vessel diameter (RVD) of 3.1±0.8 mm, minimum lumen diameter (MLD) of 0.5±0.6 mm, and a corresponding diameter stenosis of 83.4%±15.8% by core lab assessment. Mean lesion length was 64.7±54.7 mm with moderate to severe calcification in 69.3% of lesions by the Peripheral Academic Research Consortium (PARC) criteria. Adjunctive calcium-modifying technology, defined as scoring or cutting balloon and/or atherectomy, was used in 22.7% of procedures. The average acute gain at the end of the procedure was 2.0±0.7 mm with a residual stenosis <50% achieved in 99.0% of lesions and a mean residual stenosis of 23.3±12.5%. There were no flow-limiting dissection, embolization, slow flow/no-reflow, or abrupt closure events at the end of the procedure. Conclusion This subanalysis of the PAD III Observational Study represents the largest report to-date of IVL treatment of heavily calcified below-the-knee (BTK) lesions in a “real-world” patient cohort. The use of S4 IVL demonstrated consistent acute safety and effectiveness outcomes consistent with prior IVL peripheral studies. These consistent outcomes were achieved with the initial use of the S4 IVL catheter for treatment of complex BTK lesions.