Nov. 2 (UPI) — For patients with stable angina, coronary artery stents may have more of a placebo effect than previously thought, researchers in England report in a new study.
Researchers from the Imperial College London analyzed findings from the ORBITA trial of 200 patients with stable angina, a common condition in adults involving patients experiencing chest pain as a result of over-exertion from restricted blood flow to the heart.
“The most important reason we give patients a stent is to unblock an artery when they are having a heart attack,” Dr. Rasha Al-Lamee, of the National Heart & Lung Institute at Imperial College London, said in a press release.
“However, we also place stents into patients who are getting pain only on exertion caused by narrowed, but not blocked arteries. It’s this second group that we studied. Surprisingly, even though the stents improved blood supply, they didn’t provide more relief of symptoms compared to drug treatments, at least in this patient group.”
Researchers compared artery-widening stenting with a simulated procedure where a stent was not implanted.
The study, published today in The Lancet, found that treatment with coronary artery stents for stable angina had no real benefit on patient symptoms or quality of life.
“Surprisingly, even though the stents improved blood supply, they didn’t provide more relief of symptoms compared to drug treatments, at least in this patient group,” Al-Lamee said.
“While these findings are interesting and deserve more attention, they do not mean that patients should never undergo the procedure for stable angina. It may be that some patients opt to have an invasive procedure over taking long-term medication to control their symptoms.”
Stable angina is often managed with beta-blocker or nitro-glycerine drugs, but can also be treated with angioplasty with stent, which is referred to as Percutaneous Coronary Intervention. Half the study participants received a stent, while the other half underwent the placebo angiogram procedure.
Participants underwent exercise tests to measure heart and lung function before and after the procedures. Researchers found the average increase in overall exercise time was 28.4 seconds for patients who had PCI and 11.8 seconds for the placebo group.
Stenting was found to significantly relieve the narrowing of the coronary artery and improved the blood supply to the heart, though researchers note the participants received levels of medication before surgery unlikely to occur in the real world and had a single-vessel form of the condition.
“It seems that the link between opening a narrowing coronary artery and improving symptoms is not as simple as everyone had hoped,” Al-Lamee said. “This is the first trial of its kind and will help us to develop a greater understanding of stable angina, a disease which affects so many of our patients every day.”