When Bypass Beats Angioplasty

Jan 23, 2008 -- Patients with complex heart disease are less likely to die or have a heart attack if treated with bypass surgery rather than angioplasty and stenting.

The finding comes from a comparison of patient outcomes after the two major types of treatment for blocked heart arteries. Patients received bypass surgery -- coronary artery bypass grafting or CABG -- or angioplasty with stenting, a nonsurgical technique in which arteries widened with a balloon catheter are propped open with mesh devices called stents.

The study looked only at patients who had two or three blocked arteries. It included all 17,400 patients treated from October 2003 through December 2004 for two or three blocked arteries in New York State.

The bottom line: Long-term outcomes were better after bypass surgery.

Edward L. Hannan, PhD, professor and associate dean for research at the University at Albany School of Public Health, Rensselaer, N.Y., and colleagues reported the findings in the Jan. 24 issue of The New England Journal of Medicine:

• Bypass patients with two blocked arteries were 29% less likely to die or suffer heart attacks than were angioplasty patients.
• Bypass patients with three blocked arteries were 25% less likely to die or suffer heart attacks than were angioplasty patients.
• Bypass patients were less likely to need a repeat procedure to open blocked arteries than were angioplasty patients.

But stent expert William O'Neill, MD, professor of medicine and cardiology at the University of Miami Miller School of Medicine, remains doubtful that bypass offers such a large survival advantage over angioplasty.

"You really do have to ask yourself why the doctors in this study chose one method over the other for these patients," O'Neill tells WebMD. "This study is not a randomized trial, and even though it has a large number of patients, it is difficult to remove the possibility of selection bias. There is a very large, multicenter, randomized clinical trial, the SYNTAX trial, which will be reported in Europe next summer. I would urge everyone to wait for those results."

Hannan says randomized trials have biases as well, as patients may not choose to participate if they fear being assigned to a highly invasive surgery.

Angioplasty/Stents Still a Good Option

The current study results are similar to earlier studies in which Hannan and colleagues compared bypass surgery to angioplasty. But those studies looked only at bare-metal stents. The current study is the first to compare bypass to angioplasty using newer drug-eluting stents, which are less likely to clog.

However, drug-eluting stents are more likely than bare-metal stents to cause blood clots. Patients who get these stents now receive aggressive anticlot treatment -- treatment that was not routine during the time of the Hannan study.

This might have biased the results in favor of bypass surgery, notes Joseph P. Carrozza, MD, of Beth Israel Deaconess Medical Center, in an editorial accompanying the study.