Abstract 19038: Insights of Optical Coherence Tomography Into the Safety and Efficacy of Coronary Intravascular Lithotripsy for Calcified Nodule Modification During Percutaneous Coronary Intervention

Background: Among calcified lesions, nodular calcium is the most challenging subset to deal with during percutaneous coronary intervention (PCI), as there are limited options available for its modification. This study was done to assess the safety, efficacy and impact of coronary intravascular lithotripsy (IVL) on calcified nodule (CN) using optical coherence tomography (OCT).

Methods: A total of 17 patients with 40 CN undergoing PCI using coronary intravascular lithotripsy were prospectively enrolled in the study. OCT parameters studied were pre-IVL minimum lumen area (MLA), calcium (Ca) score, number of CN, proximal and distal reference diameter, post-IVL gain in MLA, calcium fracture, major dissection, post-PCI minimum stent area (MSA), stent expansion, apposition, edge dissection and spherical index at CN. Spherical index was calculated by dividing the shortest and longest diameter at CN after stent placement. The primary safety endpoint was freedom from major adverse cardiovascular events (death, MI and target vessel revascularization) during hospitalisation and at 30 days. Primary efficacy endpoints were gain in MLA after stent placement and stent expansion.

Results: Pre-IVL mean MLA at CN was 3.87±2.25mm ² , Ca score was 3.94±0.24, Ca arc 190.59±54.02 ^o , Ca depth 0.97±0.31mm, Ca length 22.73±9.87mm and CN height-1.04±0.30 mm. All 17 (100%) patients developed Ca fractures, post-IVL MLA at CN was 5.20±2.31mm ² , CN height 0.83±0.19mm and luminal gain at CN was 0.76 ± 1.71mm ² . 10 (58.8%) patients developed fractures at base of CN and rest developed fractures at apex. Patients with fractures at base showed decrease in luminal area after IVL due to luminal shift of nodule, but all these patients had good stent expansion, likely due to Ca softening. Post-IVL OCT showed minor dissections in 5 (29.4%) and major in 3 (17.6%) patients. There was no perforation, slow flow or abrupt vessel closure. Stent expansion and MSA at CN was 107.12 ± 18.98% and 8.57±2.54 mm ² respectively with spherical index of 0.83±0.12. All patients were free of MACE during hospitalization and at 30 days.

Conclusion: Coronary intravascular lithotripsy is safe and effective for modification of coronary calcified nodules during percutaneous coronary intervention.