Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) is performed to improve angina and quality of life, although blinded randomized evidence has been limited. The ORBITA-CTO trial, published in the Journal of the American College of Cardiology, evaluated CTO PCI in a randomized, blinded, placebo-controlled trial.

This multicenter trial included patients with angina attributable to a single-vessel CTO and no additional obstructive coronary disease. Following coronary assessment with dual-injection angiography, patients were randomized to CTO PCI or a placebo procedure. Blinding was maintained using procedural masking methods, including sedation and sensory isolation. Anti-anginal therapy was discontinued at randomization and later resumed through a patient-initiated protocol. The primary endpoint was an angina symptom score integrating daily symptom burden, anti-anginal use, and override events.

Fifty patients were randomized (CTO PCI n=25; placebo n=25). One patient allocated to PCI did not complete the procedure due to a complication; all patients were included in the primary analysis. At 6 months, CTO PCI resulted in improvement in angina symptom score compared with placebo (odds ratio [OR] 4.38, 95% credible interval [CrI] 1.57 to 12.69; Pr[Benefit]=0.996).

A lower frequency of angina episodes was observed (OR 4.38, 95% CrI 1.55 to 11.78; Pr[Benefit]=0.997), corresponding to 30.6 additional days without angina (95% CrI 11.1 to 50.7; Pr[Benefit]>0.999). Improvements were also observed in Seattle Angina Questionnaire (SAQ) domains and the Canadian Cardiovascular Society class. Blinding was maintained among patients, staff, and researchers.

These findings indicate that CTO PCI improves angina outcomes compared with placebo in patients with symptomatic single-vessel CTO.