OCT vs Angiography for Guidance of Percutaneous Coronary Intervention of Calcified Lesions

Importance: The use of intravascular imaging for calcified plaque characterization and preparation has been advocated over conventional methods to improve percutaneous coronary intervention (PCI) outcomes, but this approach has never been evaluated. Objective: To determine if optical coherence tomography (OCT) is superior to angiography for calcified lesions PCI guidance. Design, Setting, and Participants: The CALIPSO (Calcified Lesion Intervention Planning Steered by OCT) trial was a prospective, multicenter, open-label, randomized clinical trial that included patients with stable moderate to severe calcified coronary lesions on coronary angiography scheduled for PCI. The trial was conducted at 12 sites in France between December 2021 and June 2023, and data were analyzed from December 2023 to April 2024. Intervention: After diagnostic coronary angiography, eligible patients were randomly assigned in a 1:1 ratio to receive OCT-guided PCI or angiography-guided PCI. In the OCT group, the procedures were guided by OCT analysis and predefined standardized management algorithms. Patients from both arms had control post-PCI OCT analysis after procedure completion for primary end point measurement. Main Outcomes and Measures: The primary end point was the minimal stent area (MSA) measured by OCT in both groups. Secondary key safety end points included periprocedural myocardial infarction, radiation dose, contrast medium volume, and procedure duration. Results: A total of 143 patients were randomized, and 134 were included in the final analysis (65 in the OCT group and 69 in the angiography group). Median (IQR) patient age was 73.0 (66.0-78.0) years, and 25 patients (18.7%) were female. The baseline characteristics of the groups were comparable, but the use of intravascular lithotripsy was more frequent in the OCT arm (30 patients [46%] vs 8 patients [12%]; P < .001). The final median (IQR) MSA was larger in the OCT group than in the angiography group (6.5 [5.5-8.1] mm2 vs 5.0 [4.1-6.1] mm2; P < .001). There was no difference in periprocedural complications incidence, contrast medium volume, or procedure duration between groups. Conclusions and Relevance: The CALIPSO randomized clinical trial showed that OCT guidance associated with predefined algorithmic management achieved better stent implantation results than angiography guidance in patients with calcified lesions PCI, without any additional safety concern. Trial Registration: ClinicalTrials.gov Identifier: NCT05301218.