Study clarifies benefits of coronary stents
Who should get stents to keep once-clogged coronary arteries open?
Someone who is having a heart attack certainly should, and the life-prolonging benefits have been demonstrated in several studies. But results have been more ambiguous for patients who have stable angina.
An Emory study by Kreton Mavromatis, director of cardiac catheterization at the Atlanta VA Medical Center, showed patients with stable angina who received stents along with medical therapy were less likely to be hospitalized than those receiving only medical therapy, 4% versus 13%, respectively.
In the study, researchers used a technique called fractional flow reserve (FFR) to decide if someone with stable angina should receive a stent or medical therapy with drugs such as aspirin and statins. Conventionally, X-ray coronary angiography is used to assess the need for a stent. FFR involves introducing a pressure sensor via guidewire into the coronary artery, to measure how much blood flow is being blocked.
Some cardiologists have criticized the results, noting that the benefits of stenting didn't reduce deaths and heart attacks.
“It is important to recognize that reducing symptoms of angina and the chance of hospitalization is a tremendous benefit to patients,” Mavromatis says. “I think FFR will play a bigger role in evaluating and treating coronary artery disease, as it can direct stenting much more precisely than angiography toward clinically important coronary artery disease, improving outcomes and saving money.”
The FFR procedure costs several hundred dollars but is significantly less expensive than a coronary stent. Habib Samady, director of interventional cardiology at Emory, also has been an advocate for the use of FFR to select who would benefit from a coronary stent.
“At Emory, we are sometimes asked to reevaluate patients who have been slated for coronary artery bypass surgery at another hospital where recommendations are made based on angiography alone,” says Samady. “When we evaluate these cases using FFR, we are sometimes able to recommend courses of treatment that involve fewer stents or even medical therapy. Occasionally, based on FFR data, we send our patients for an endoscopic or ‘minimally invasive' bypass and stent the remaining narrowings.”
A large, multi-center study called ISCHEMIA is starting that will address the coronary stent versus medical therapy issue in a more definitive way. Both Emory and the Atlanta VA Medical Center are participating.
