Percutaneous Coronary Intervention in Stable Angina (ORBITA)

ORBITA did something almost never attempted: it put a heart procedure up against a placebo procedure, with everyone — patient and assessor — kept blind to who got which. The result was one of the most provocative trials of the decade.

Patients with stable angina and a severe single-vessel blockage were medically optimized, then randomized to receive a stent or a sham catheterization in which no stent was placed. Six weeks later, the stented patients had gained essentially nothing in exercise time over the sham group — a difference of about 16 seconds that did not reach significance. The relief patients reliably reported after stenting appeared, under blinded conditions, to owe a great deal to expectation.

The finding does not touch the use of stents in heart attacks, where they save lives. But for stable angina, it forced an honest reckoning: opening a narrowed but stable artery may relieve symptoms far less than its reputation suggested, once the placebo effect is stripped away.

We rate the evidence very strong. Small in size but exceptional in rigor — a true blinded, sham-controlled design — ORBITA reset expectations for one of the most common procedures in cardiology.