Heart Bypass Surgery Rate Is Declining

May 3, 2011 -- There has been a dramatic drop in the rate of heart bypass procedures performed in the U.S. over the last decade, even though more hospitals are offering the open-heart surgery.

One-third fewer coronary artery bypass graft (CABG) surgeries were performed in 2008 compared to 2001, while the rate of less invasive angioplasty procedures remained largely unchanged, according to a study in the Journal of the American Medical Association.

More than a million coronary revascularizations, involving either CABG or angioplasty with or without stenting, are performed in the U.S. each year to fix blocked arteries that supply blood to the heart.

In 2008, three out of four revascularization patients had angioplasties instead of CABG, compared to two out of three patients a decade ago, Peter W. Groeneveld, MD, of the University of Pennsylvania School of Medicine tells WebMD.

“This is a problem, because it does actually matter which of these surgeries patients get,” he says, adding that many patients who would be expected to have better outcomes with CABG may not be offered the surgery.

CABG Trends

Using a nationally representative sample of heart patients treated at 1,000 hospitals across the U.S., Groeneveld and colleagues were able to analyze trends in revascularization practices from 2001 to 2008.

During this period, the annual rate of CABG surgeries declined steadily for all patient subgroups and across all regions of the country.

And at the same time CABG surgeries were dropping, the number of hospitals offering the procedure increased by 12%.

In 2008, about 25% of hospitals offering CABG performed fewer than 100 of the surgeries a year, compared to about 10% of hospitals in 2001.

Groeneveld says this trend is particularly disturbing.

“If fewer CABG surgeries are being done, but more hospitals are doing them it will be harder to maintain the volume that might be necessary to guarantee the best outcomes,” he says. “It isn’t clear what the best number is, but 100 surgeries a year as a minimum has been considered standard. Now we find that a quarter of hospitals offering CABG don’t even do 100 a year.”

CABG vs. Angioplasty

Current treatment guidelines from the American Heart Association and the American College of Cardiology favor CABG over angioplasty for patients with the most severe disease: those with severe narrowing of three major coronary arteries and those with narrowing of the left main artery if they are healthy enough for surgery.

Cardiologist and University of Michigan Health System professor of internal medicine Kim A. Eagle, MD, who led the ACC/AHA guidelines task force, says these patients now represent a small percentage of revascularization candidates.

“We have made quite a bit of progress in the secondary prevention arena, whether it be smoking cessation or more effective management of high cholesterol, hypertension, and diabetes,” he tells WebMD. “So the number of patients who show up with severe three-vessel disease is going down.”

Technological advances in cardiac stenting may also be a factor in the decline in CABG surgeries, he says.

“Multi-vessel angioplasty is now an appropriate alternative to bypass surgery for patients who don’t fit into these very high-risk groups,” he says. “And if it is a close call, patients are likely to opt for the less invasive procedure.”