ORBITA: PCI no better than meds for stable angina

DENVER – The first-ever blinded, sham-controlled randomized trial of percutaneous coronary intervention for stable angina failed to show a significant improvement in exercise time for PCI, compared with placebo PCI, Rasha Al-Lamee, MD, reported at the Transcatheter Cardiovascular Therapeutics annual educational meeting.

The blockbuster results of the ORBITA trial, published online in the Lancet simultaneously with Dr. Al-Lamee’s presentation in Denver, quickly went viral, with a story splashed across the front page of the New York Times under the headline “‘Unbelievable’: Heart Stents Fail to Ease Chest Pain.” Interventional cardiology thought leaders at TCT said the newspaper piece, and a Lancet editorial commentary entitled “Last nail in the coffin for PCI in stable angina?” that accompanied publication of ORBITA, failed to convey the study’s major limitations, drawbacks that Dr. Al-Lamee readily acknowledged.

^{Bruce Jancin/Frontline Medical News}

Dr. Rasha Al-Lamee

^{Bruce Jancin/Frontline Medical News}

Dr. Martin B. Leon

What ORBITA did

ORBITA (Objective Randomized Blinded Investigation with Optimal Medical Therapy of Angioplasty in Stable Angina) included 200 patients referred to five U.K. cardiac catheterization labs for diagnostic angiography. Participants had to have stable angina, single-vessel disease, and at least one 70% or greater stenosis; in fact, their stenotic severity averaged 84.4% by quantitative coronary angiography.

The patients received 6 weeks of intensive medical therapy during which they were uptitrated to an average of three antianginal medications. They then underwent either real or sham PCI followed by 6 weeks of recovery, during which both the patients and care team remained blinded. Then the same assessments done before randomization were repeated, including exercise treadmill testing, the Seattle Angina Questionnaire, and dobutamine stress echocardiography, explained Dr. Al-Lamee of Imperial College London.

The primary outcome was achievement of at least a 30-second greater improvement in total exercise time following PCI, compared with sham PCI, an effect size chosen based on placebo-controlled studies of antianginal drugs. The PCI group improved by a mean of 28.4 seconds, the controls by 11.8 seconds, and the resultant 16.6-second difference made for a negative result (Lancet. 2017 Nov 2;doi: 10.1016/S0140-6736[17]32714-9).

PCI did, however, result in significant improvement in the secondary endpoint of ischemia reduction as assessed by blinded evaluation of dobutamine stress echocardiography results. The PCI group’s mean peak stress wall motion index score improved from 1.11 prerandomization to 1.03 – that is, normal – at follow-up 6 weeks post procedure while remaining unchanged in the sham PCI group, Dr. Al-Lamee noted at the meeting, sponsored by the Cardiovascular Research Foundation.

What the results mean

Dr. Al-Lamee said the ORBITA results should enable cardiologists to sit with patients similar to those in the trial and have a more informed, patient-centered discussion in which intensive medical management can be offered as an initial first-line option with an understanding that it will likely improve their symptoms to the same degree as angioplasty.

“There will be those patients who would rather avoid having to take high doses of antianginal medications with the side effects they involve, who may well prefer to have an upfront procedure with a small risk in order to reduce their pill count, and who also would rather have improved blood flow to the heart, which may have prognostic implications,” Dr. Al-Lamee said.

Carl L. Tommaso, MD, part of the panel of discussants at the late-breaking clinical trials session in which Dr. Al-Lamee presented the ORBITA findings, applauded the investigators for their ingenious study design, which included elaborate blinding techniques involving music played through headphones throughout the procedure, heavy sedation, separate angioplasty and clinical care teams, the same postprocedural instructions and discharge letter, and dual-antiplatelet therapy in both study arms.

“This is a great study. I don’t think any of us could get this study past an institutional review board in the United States,” commented Dr. Tommaso, director of the cardiac catheterization laboratory at Skokie (Ill.) Hospital.

He added, however, that he wouldn’t have performed PCI on the basis of angiographic findings alone in stable angina patients with a 9-minute treadmill exercise time.