Intravascular Lithotripsy for Peripheral Artery Calcification: 30-Day and 6-Month Outcomes from the RESTORE ATK Study

To evaluate the safety and effectiveness of intravascular lithotripsy (SEISMIQ intravascular lithotripsy [IVL] system; Boston Scientific Corporation, Marlborough, Massachusetts) for treating calcified above-the-knee (ATK) lesions in patients with peripheral artery disease.

RESTORE ATK was a prospective, single-arm study that enrolled from 10 sites between January 20, 2023, and December 13, 2023. Ninety-five patients with de novo, moderate to severe calcifications of the femoropopliteal segments were treated using the tested device to modify calcium. Adjunctive drug-eluting technology was not permitted. Primary endpoints were <50% residual diameter stenosis after IVL treatment (by independent core laboratory-adjudicated angiography) and 30-day incidence of major adverse events (MAEs): death, clinically driven target lesion revascularization (CD-TLR), or major amputation. Secondary endpoints included patency, ankle-brachial index, and Rutherford classification (RC) through 6 months.

Baseline RC included RC2 (23.2%), RC3 (70.5%), or RC4 (6.3%). Lesions averaged 96.0 mm in length, with 93.7% severely calcified and a mean baseline diameter stenosis of 93.7%. Postprocedural residual stenosis of <50% was achieved in all patients, meeting the predefined performance goal. Three patients (3.2%) received provisional stent placement. Patients had a mean residual stenosis of 21.2% and acute luminal gain of 3.2 mm. No MAEs occurred through 30-day follow-up. At 6 months, target lesion patency was 66.3%, and freedom from CD-TLR was 97.9%. A high proportion of patients demonstrated ≥1 RC improvement at 30-day (93.5%) and 6-month (91.2%) follow-up.

This IVL system demonstrated effective treatment of calcified ATK lesions by successfully reducing calcific stenoses with minimal complications and sustained clinical improvement through 6 months.