Al-Lamee R, et al. - A double-blind, randomised controlled trial was undertaken to assess the efficacy of percutaneous coronary intervention (PCI) in stable angina. Compared to the effect of a placebo procedure, PCI did not increase exercise time in patients with medically treated angina and severe coronary stenosis. As is standard for pharmacotherapy, the efficacy of invasive procedures can be assessed with a placebo control.

Methods

• ORBITA is a blinded, multicentre randomised trial of PCI versus a placebo procedure for angina relief.
• This trial was performed at five study sites in the UK.
• Patients with severe (≥70%) single-vessel stenoses were included.
• Patients received 6 weeks of medication optimisation after enrolment.
• Then, patients underwent pre-randomisation assessments with cardiopulmonary exercise testing, symptom questionnaires, and dobutamine stress echocardiography.
• By using an automated online randomisation tool, researchers randomized patients 1:1 to undergo PCI or a placebo procedure.
• The assessments done before randomisation were repeated at the final assessment after 6 weeks of follow-up.
• For this study, the primary endpoint was difference in exercise time increment between groups.
• Based on the intention-to-treat principle, they performed all analyses.
• The study population contained all participants who underwent randomisation.

Results

• Two hundred and thirty patients with ischaemic symptoms were included in ORBITA.
• After the medication optimisation phase and between Jan 6, 2014, and Aug 11, 2017, they performed randomization of 200 patients; 105 patients were assigned PCI and 95 were assigned the placebo procedure.
• In this study, lesions had mean area stenosis of 84·4% (SD 10·2), fractional flow reserve of 0·69 (0·16), and instantaneous wave-free ratio of 0·76 (0·22).
• Findings revealed no marked difference in the primary endpoint of exercise time increment between groups (PCI minus placebo 16·6 s, 95% CI -8·9 to 42·0, p=0·200). No deaths were observed.
• Serious adverse events observed were four pressure-wire related complications in the placebo group, which required PCI, and five major bleeding events, including two in the PCI group and three in the placebo group.