Intravascular Lithotripsy for the Management of In-Stent Restenosis Due to Underexpanded Stents or Calcific Neo-Atherosclerosis: Outcomes From a Single-Center Study.

Background Treatment of calcific neo-atherosclerosis/stent underexpansion due to inadequate calcific plaque modification continues to pose significant challenges. Intravascular lithotripsy (IVL) can cause fractures in the calcific plaques, facilitating adequate stent expansion and lumen. Objective Our objective is to assess the effectiveness of IVL in achieving optimal minimal stented area (MSA) in patients with in-stent restenosis (ISR) and 30-day cardiovascular and bleeding outcomes. Methods This is a single-center retrospective observational study conducted at a tertiary hospital. Patients who were noted to have ISR with underexpanded stents and calcific neo-atherosclerosis who did not achieve optimal MSA with non-compliant/cutting/scoring balloons were included in the study. IVL was utilized for plaque modification. Subsequently, MSA was measured post-IVL. The primary outcome included achievement of optimal MSA (defined as at least 80% of native vessel or gain in MSA of 1-2 mm²); secondary outcomes were readmission for acute coronary syndrome, major bleeding, and target lesion revascularization. Results A total of 19 patients and 20 lesions were included in the study. Left main (LM), left anterior descending (LAD) artery, right coronary artery (RCA), and circumflex (Cx) were culprit vessels in 5%, 60%, 10%, and 25% of cases, respectively. MSA before IVL use was 4.7, 3.23±0.41, 3.5, and 3.3±0.15, respectively, in LM, LAD, Cx, and RCA. After IVL, optimal MSA was achieved in all three vessels. The average follow-up was 3.6 months; two patients were readmitted with anemia secondary to GI bleed, while one patient was readmitted with angina and required repeat revascularization. Conclusion IVL is an excellent tool for the management of ISR secondary to underexpanded stents and calcific neo-atherosclerosis.