Jefferson cardiologists have found that using stents instead of angioplasty in patients with recurrent blockage following coronary-artery bypass surgery lowers the risk of death, heart attack and the need for repeat bypass surgery or angioplasty.
Published in The New England Journal of Medicine in September, the study is "a major step by Jefferson clinical researchers to help find new ways of treating heart patients. It shows a less invasive technique of preventing patients from requiring repeat open heart surgery," according to Howard H. Weitz, MD, Professor of Medicine and Director, Division of Cardiology, Department of Medicine, Jefferson Medical College (JMC).
New Hope for Bypass Patients
"These findings represent new hope for the hundreds of thousands of patients who undergo bypass surgery each year," says Dr. Weitz. "Many of these patients later experience complications associated with the reclosure of the vein grafts used to construct the bypass." Dr. Weitz says 501,000 coronary-artery bypass surgery procedures were performed in the United States in 1994 alone.
Coronary-artery bypass surgery uses veins from the leg to channel blood from the aorta to branches of the coronary arteries, increasing blood flow beyond the obstruction.
"The physical nature of a vein graft makes it prone to reclosure. Within 10 years of surgery, nearly half of all bypass grafts are obstructed setting the stage for recurrent angina or heart attack," explains the study's principal investigator Michael P. Savage, MD, Associate Professor of Medicine, Division of Cardiology, JMC, and Director, Cardiac Catheterization Laboratory at Thomas Jefferson University Hospital.
Traditionally, balloon angioplasty had been used as an alternative to repeat surgery to reopen the vein grafts that clog with plaque.
"The poor long-term outcomes of angioplasty in these patients led us to investigate the use of coronary stents to reopen clogged vein grafts in our multicenter study," Dr. Savage explains.
David L. Fischman, MD, Associate Professor of Medicine, Division of Cardiology, JMC, and Associate Director, Cardiac Catheterization Laboratory at Jefferson, served as a co-investigator on the study and directed the core laboratory performing angiographic analysis.
Trial Studies 220 Patients with Restenosis
The trial consisted of 220 patients with obstructed bypass vein grafts randomized into two groups. One group received angioplasty to remove the obstruction, the other received Palmaz-Schatz stents (Johnson & Johnson). Six months after their procedure, patients underwent a follow-up angiogram.
"Our follow-up demonstrated that the patients who received stents had better long-term clinical results," says Dr. Savage.
"Most importantly, the stented group experienced a 36 percent reduction in complications, including death, heart attack and repeat bypass surgery and angioplasty."
Dr. Savage believes that the results of the study, which led to the December 1996 FDA approval of Palmaz-Schatz stents for the treatment of coronary artery bypass graft disease, points toward a new standard of care.
"It is exciting to know that stents can offer new hope for patients whose long-term outlook was previously poor."
In addition to Jefferson, 12 other centers around the nation collaborated on the study.
In a related effort, an editorial by Dr. Fischman published in The Journal of the American Medical Association (JAMA) in August expressed support for the preventive effects of an intravenous "super aspirin" given patients before angioplasty. Dr. Fischman's editorial accompanied a study by the Cleveland Clinic Foundation, Ohio, showing that abciximab (ReoPro™, Centocor, Inc., Malvern, PA) can prevent platelets from sticking to arterial walls and reclogging vessels after the angioplasty procedure.
In the editorial, of which Dr. Savage is co-author, the author notes that the benefits of ReoPro™ are greatest in highest risk patients with acute heart attack or medically unstable angina, They point out that patient profiles, drug costs and other interventional alternatives (including stents) are issues to consider when deciding who should receive this "super aspirin"