Five years after the procedures, 90.7% of the bypass patients and 89.7% of the angioplasty patients were still alive, says Mark A. Hlatky, MD, senior author of the analysis and a professor of health research and policy and professor of medicine at Stanford University School of Medicine in Palo Alto.
"Although only a few of the studies followed patients more than five years, there was no appreciable difference [in survival] at 10 years," he says.
Complications do differ between the two procedures, however.
Hlatky and colleagues stress that their analysis only applies to a select group of heart patients: those for whom either procedure would be considered a reasonable choice.
For patients who are eligible for either heart intervention, "either is feasible," Hlatky tells WebMD.
The report is released early online and will be published in the Nov. 20 issue of the Annals of Internal Medicine.
CABG vs. Angioplasty
The researchers evaluated the results of 23 clinical trials in which 5,019 patients were randomly assigned to get angioplasty with or without stents, also called catheter-based percutaneous coronary intervention or PCI, and 4,944 were assigned to get coronary artery bypass graft surgery, also called CABG.
The average age of patients was 61; 73% were men.
Heart Intervention Procedures
In angioplasty, interventional cardiologists push a balloon-like device into the coronary arteries and inflate the balloon to widen the vessel. An expandable wire mesh tube called a stent may be inserted to keep the vessel open. Some stents are coated with drugs meant to help prevent the artery from clogging up. In 2005, about 645,000 angioplasty procedures were done in the U.S.
In bypass surgery, cardiac surgeons harvest a segment of a healthy blood vessel from another part of the body and use it to bypass the clogged artery or arteries, rerouting the blood to improve blood flow to the heart. About 261,000 bypass procedures were done in the U.S. in 2005.
CABG vs. Angioplasty: Findings
Besides similar survival rates overall, the researchers found no significant survival differences between the two procedures for patients with diabetes, although earlier research had seemed to favor bypass surgery. But Hlatky says ongoing studies looking more closely at diabetic patients will yield a more definitive answer.
Similar numbers of patients suffered heart attacks within five years of the procedures. While 11.9 of those who got angioplasty had a heart attack within five years, 10.9% of those who got bypass did.
Repeat procedures were more common in angioplasty patients. While 46.1% of angioplasty patients who didn't get a stent needed repeat procedures, 40.1% of those who got a stent did. But just 9.8% of surgery patients needed another procedure.
The study didn't include information on drug-coated stents, which have been found in some studies to increase risk of blood clots and other problems.
Bypass Surgery, Angioplasty: Pros and Cons
Each procedure has downsides and benefits, the researchers found. Bypass surgery, Hlatky says, "is longer lasting, more durable, and gives more angina relief."
The downsides? "There is a higher risk of stroke during the procedure, and a longer recovery time."
Angioplasty is a ''simpler procedure and the recovery is faster," he says. Downsides: "It is very likely you will need a second procedure within six months. And there is not as much chest pain [angina] relief."
Strokes during the interventions occurred in 1.2% of bypass surgery patients and 0.6% of angioplasty patients. While 79% of angioplasty patients got angina relief at five years, 84% of surgery patients did.
The new analysis is "very complete," says Kim A. Eagle, MD, director of the Cardiovascular Center and Albion Walter Hewlett Professor of Internal Medicine at the University of Michigan, Ann Arbor.
The study shows, he says, that if either procedure is considered appropriate for an individual patient, the decision can rest on patient attitudes and preferences.
While he finds some patients prefer to undergo bypass surgery, especially with its lower need to repeat, others want to avoid surgery and prefer angioplasty.
"If you are uncertain, get a second opinion," he says. "Ask hard questions." Such as: "What would be the downside of angioplasty in my situation? Any factors I have that might make you want to think about bypass instead of angioplasty? Is there a compelling reason to do anything? Is medical therapy equal to intervention [for me] in terms of preventing heart attack or death?"
Another expert, Curtis Hunter, MD, director of cardiothoracic surgery at Santa Monica-UCLA Medical Center & Orthopaedic Hospital in Santa Monica, Calif., says it is important for patients to realize the studies cover the least sick of heart disease patients, those for whom either procedure is considered appropriate.
"The two procedures are only shown to be equal in a very small subset and the healthiest portion of the population [with heart disease]," he says.