DALLAS, June 23 -- Surgeons have pioneered a new type of triple coronary artery bypass surgery that may offer advantages over current operations, according to a report in today's Circulation: Journal of the American Heart Association.
The procedure uses three artery grafts while a traditional bypass uses two artery grafts and a vein graft from the leg.
In a seven-year study, researchers found the new procedure extended lives, prevented new heart attacks and reduced the rate of recurrent chest pain compared to traditional bypass, says lead author, Jan G. Grandjean, M.D., Ph.D., of the Thoraxcenter at the University Hospital of Groningen, the Netherlands. Coronary artery bypass surgery improves blood supply to the heart in individuals whose blood vessels are narrowed from atherosclerosis. The procedure involves attaching a section or "graft" taken from one or more healthy blood vessels from one part of the body to reroute blood supply from the narrowed blood vessel. Each year surgeons perform about 500,000 such procedures.
In an accompanying editorial, Denton A. Cooley, M.D., one of the foremost heart surgeons in the United States, and a pioneer in bypass surgery, complimented the researchers on their "excellent" results.
"Considering that all of these people had triple-vessel disease, this rate is extremely satisfactory," says Cooley, surgeon-in-chief at the Texas Heart Institute in Houston. "No other investigation has published a longer follow-up study regarding the combined use of abdominal and bilateral mammary grafts." According to Cooley, the evidence clearly shows the advantages of using arteries rather than vein grafts in bypass procedures. Arteries provide sufficient blood flow to the heart, yet are far less susceptible to accelerated clogging and subsequent repeat bypass surgery.
However, he cautioned that the procedure may have risks and there may not be enough cardiac surgeons in the United States adequately trained in triple arterial grafting for the procedure to become widely used any time soon. "Because of a steep learning curve, only highly skilled surgeons should attempt triple arterial bypass described by Grandjean. As with any other operation, the surgeon must use sound judgment and must tailor the procedure to fit each individual case."
"Although the results favor the use of triple arterial bypass, further studies are needed to draw meaningful conclusions about this approach," Cooley comments. Grandjean, who began using abdominal grafts in 1989, noted that while it is difficult to compare data on patients who have undergone bypasses using vein grafts and/or single or double grafts, the study's findings successfully demonstrate the benefits of triple-artery grafts.
"In most patients with three-vessel disease, the two internal mammary arteries do not provide enough graft material to deliver enough blood supply to the heart," says Grandjean. Rather than using an inferior vein graft, the Dutch researchers tested a third option -- a portion of the graft located in the abdomen, the gastroepoploic artery, along with two mammary grafts.
In the longest follow-up study to date, Grandjean and co-investigator, T. Margot Bergsma, M.D., evaluated 256 people seven years after triple bypass surgery. Survival rate among triple-artery recipients was 91.1 percent. Survival rates in published studies for bypass patients receiving vein and/or artery grafts range from 88 to 92 percent. The rate of subsequent heart attacks in triple-artery recipients, about 3 percent, was better than the 5 percent average reported among vein and/or artery bypass patients, and repeat surgeries were unnecessary for 95.4 percent of the triple-artery grafts, which also is comparable to vein/artery bypass rates.
Fully 85.4 percent of individuals remained free of angina (chest pain) at seven years, compared to an average 60 percent reported among vein/artery recipients. Chest pain is caused by inadequate blood flow to the heart.
Because the triple-bypass procedure requires grafting an abdominal artery in addition to the mammary arteries, surgically harvesting it requires an abdominal extension of the sternal incision. This extension prolongs operating time, often increases postoperative pain and adds to the risk of hernia and/or adhesion formation, points out Cooley.
"Should abdominal surgery later become necessary, optimal management would be unclear," he says. "Although triple artery bypass may be ideal from a theoretical standpoint, caution is necessary in using this approach." Co-authors are Adriaan Voors, M.D., Ph.D.; Piet Boonstra, M.D., Ph.D.; Peter den Heyer, M.D., Ph.D.; Tjark Ebels, M.D., Ph.D.
Media advisory: Dr. Grandjean can be reached at (31) 50-361-3238 or fax (31) 50-361-1347, e-mail: J.G.Grandjean@thorax.azg.nl.
(Please do not publish numbers.)