Intravascular Lithotripsy in Left Main Stem Percutaneous Coronary Intervention

ABSTRACT Background IVL is increasingly used for coronary calcium modification; however, prospective data for its use in LMS lesions are lacking. Aims To evaluate the feasibility, safety, and mechanical efficacy of intravascular lithotripsy (IVL) for calcium modification in calcified distal left main stem (LMS) percutaneous coronary intervention. Methods In this prospective, multicentre, open‐label study across five United Kingdom centers (NCT04319666), 50 patients with obstructive distal LMS disease and IVUS‐confirmed circumferential calcification (maximum calcium arc ≥ 270° in at least one segment) underwent IVL‐assisted PCI. IVUS was mandated at pre‐treatment, post‐IVL, and post‐stent timepoints with independent core laboratory analysis. Co‐primary endpoints were IVUS‐assessed minimum stent area (MSA) and 30‐day major adverse cardiac events (MACE). Results Fifty patients underwent IVUS‐guided LMS PCI with IVL for calcium modification. Device crossing was successful in all 50 cases. Mean LMS MSA was 13.36 ± 3.20 mm 2 (95% CI 12.44–14.28 mm 2 ); 84% of patients (41/49) achieved an LMS MSA exceeding 11 mm 2 . Significant luminal gain was observed across all territories (LMS 7.19 ± 3.52 mm 2 , p < 0.001). IVUS‐visible calcium fracture was not associated with stent expansion. There were no periprocedural deaths or myocardial infarctions and no MACE at 30 days. At 12 months, MACE occurred in 4 patients (8.0%) with no stent thrombosis. Conclusions IVL is safe and mechanically efficacious for calcium modification in severely calcified distal LMS disease, achieving stent expansion exceeding prognostically validated thresholds with favorable clinical outcomes at 12 months. Clinical trial registration clinicaltrials.gov NCT04319666.