Safety, efficacy, and optical coherence tomography insights into intravascular lithotripsy for the modification of non‐eruptive calcified nodules: A prospective observational study

Abstract Background Non‐eruptive calcium nodules (CNs) are commonly seen in heavily calcified coronary artery disease. They are the most difficult subset for modification, and may result in stent damage, malapposition and under‐expansion. There are only limited options available for non‐eruptive CN modification. Intravascular lithotripsy (IVL) is being explored as a potentially safe and effective modality in these lesions. Aims This study aimed to investigate the safety and efficacy of the use of IVL for the modification of non‐eruptive CNs. The study also explored the OCT features of calcium nodule modification by IVL. Methods This is a single‐center, prospective, observational study in which patients with angiographic heavy calcification and non‐eruptive CN on OCT and undergoing PCI were enrolled. The primary safety endpoint was freedom from perforation, no‐reflow/slow flow, flow‐limiting dissection after IVL therapy, and major adverse cardiac events (MACE) during hospitalization and at 30 days. MACE was defined as a composite of cardiac death, myocardial infarction (MI), and ischemia‐driven target lesion revascularization (TLR). The primary efficacy endpoint was procedural success, defined as residual diameter stenosis of <30% on angiography and stent expansion of more than 80% as assessed by OCT. Results A total of 21 patients with 54 non‐eruptive CNs undergoing PCI were prospectively enrolled in the study. Before IVL, OCT revealed a mean calcium score of 3.7 ± 0.5 and a mean MLA at CN of 3.9 ± 2.1 mm 2 . Following IVL, OCT revealed calcium fractures in 40 out of 54 (74.1%) CNs with an average of 1.05 ± 0.72 fractures per CN. Fractures were predominantly observed at the base of the CN (80%). Post IVL, the mean MLA at CN increased to 4.9 ± 2.3 mm 2 . After PCI, the mean MSA at the CN was 7.9 ± 2.5 mm 2 . Optimal stent expansion (stent expansion >80%) at the CN was achieved in 85.71% of patients. All patients remained free from MACE during hospitalization and at the 30‐day follow‐up. At 1‐year follow‐up, all‐cause death had occurred in 3 (14.3%) patients. Conclusions This single‐arm study demonstrated the safety, efficacy, and utility of the IVL in a subset of patients with non‐eruptive calcified nodules. In this study, minimal procedural complications, excellent lesion modifications, and favorable 30‐day and 1‐year outcomes were observed.