WHY THIS STUDY?

Calcified lesions are associated with an increase of periprocedural complications and adverse clinical events following PCI. The use of intravascular imaging to analyze plaque characteristics and to guide its preparation according to pre-defined algorithms during PCI has been previously proposed. However, OCT guided management of complex calcified lesion has never been evaluated versus conventional angio-guided PCI methods. The CALIPSO trial (NCT05301218) aimed to assess OCT-guided algorithm's superiority over angio-guidance for calcified lesions PCI strategy. We hypothesized that the strict guidance of PCI strategy by OCT criteria to appropriately choose the most adapted preparation strategy, stent sizing, and procedure optimization could provide a final larger minimal stent area than classical angiography-based strategy, without impacting the security of the patient. 

HOW WAS IT EXECUTED?

The CALIPSO trial is a prospective, multicenter, randomized, superiority trial that compared OCT-guided and angiography-based PCI strategy in patients with stable moderately to severely calcified coronary lesions (Mintz classification).   Patients included in the study were randomized between the OCT-guidance group and the control group in a 1:1 fashion. Patients from the OCT group were treated according to a predefined algorithm based on the pre-PCI OCT analysis of the target lesion  whereas patients from the angio group were treated at the discretion of the operator. FInal OCT analysis was acquired in both arms after stent implantation and optimization. The OCT and angiography data were reviewed in a centralized corelab. The clinical and procedural characteristics were entered into a predefined on-line standardized case report form. Clinical follow-up were obtained by clinic visits and/or by telephone contact. The primary endpoint of the CALIPSO study is the minimal stent area (MSA) on the final OCT run. Secondary endpoints include: Geometrical stent expansion; residual post PCI stenosis (assessed by QCA methods); residual major struts malapposition; Target vessel failure at 30 days and 1 year (composite of death from cardiac causes, target-vessel myocardial infarction, or ischemia-driven target-vessel revascularization.);  peri-procedural MI, coronary artery perforation incidence; radiation dose & contrast medium volume; procedure duration

WHAT WERE THE ESSENTIAL RESULTS?

A total of n=143 patients were included in the study (n=72 OCT group vs. n=71 Angio group). The baseline clinical and angiographic characteristics of the patients were comparable but the lesion preparation strategies differed between groups. Hence, patients from the OCT group were more frequently treated with Iitravascular lithotripsy (38% vs 7%) and less frequently with non-compliant balloon predilation (43% vs. 63%) than the others (p<0.05 for both). We aim to present the results of the primary endpoint and secondary imaging endpoint analyses at the next EuroPCR 2024 meeting (60% of the data were analyzed on December the 31st 2023). We will also be able to present the 30 days clinical endpoint.

WHY IT IS IMPORTANT?

The CALIPSO trial is the first attempt to prospectively evaluate the use of OCT guidance for complex calcified lesions PCI. The results of the trial will indicate if OCT guidance is safe and superior to angiography guidance for achieving better stent implantation results.

PLEASE LIST THE DEVICE(S)/TECHNOLOGY(IES) INVOLVED IN THIS TRIAL

OCT catheters and analysis softwares (Abbott) Rotablator (Boston Scientific) Shockwave C2 catheter (Shockwave Medical)