Intravascular Lithotripsy for Patients with Chronic Limb-Threatening Ischemia: Study Protocol for CALCIO, a Prospective Multicenter Observational Investigation

Journal article

Purpose: The prevalence of severe vascular calcification in patients with Chronic Limb-Threatening Ischemia (CLTI) hinders the outcome of endovascular interventions and increases the risk of amputation and death. Intravascular lithotripsy (IVL) is a safe and effective treatment that promotes revascularization; however, large-scale data on its long-term effectiveness are lacking. The Chronic Limb-Threatening Ischemia treated with Intravascular Lithotripsy Observational Study (CALCIO) aims to address this shortcoming by assessing the real-world, long-term outcomes of IVL in a large cohort of patients with CLTI. Methods: CALCIO is a worldwide, multicenter, prospective cohort study designed to follow for 2 years 400 participants treated with the Shockwave Medical IVL System. Eligible patients, adults (≥ 18 years) with CLTI (Rutherford category ≥ 4) and calcified femoro-popliteal and/or crural lesions visible on fluoroscopy, are recruited upon providing informed consent. The primary outcome measure is a composite of wound healing and freedom from amputation at 12 months. Secondary outcome measures include technical success, amputation-free survival, changes in Rutherford category, limb perfusion and wound, ischemia, and foot infection (WIfI) score, patency, need for revascularization, safety, and patient-reported health-related quality of life (HRQoL). Results will be reported using mainly descriptive statistics. Patient enrollment opened in July 2024 and is planned to continue until July 2026, with the follow-up period expected to end in July 2028. Conclusion: CALCIO intends to provide valuable insights into the real-world long-term clinical outcomes of IVL to support decision making regarding the optimal endovascular treatment for CLTI patients. CALCIO is registered on ClinicalTrials.gov (NCT06149650). Graphical Abstract:

Authors: Uberoi, R; Reimer, P; Chun, J; Goyault, G; Kashef, E

• Alternative title: R. Uberoi et al.: Intravascular Lithotripsy for Patients with Chronic Limb-Threatening..
• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer
• Journal: CardioVascular and Interventional Radiology
• Volume: 49
• Issue: 6
• Pages: 1219-1226
• Publication date: 2026-02-17
• Acceptance date: 2025-12-19
• DOI: 10.1007/s00270-025-04335-w
• EISSN: 1432-086X
• ISSN: 0174-1551
• Language: English
• Keywords: Intravascular lithotripsy; Peripheral arterial disease; Chronic limb-threatening ischemia; Vascular calcification; Endovascular treatment