What's new in bypass vs. stent
When cholesterol-filled plaque severely narrows a coronary artery and causes chest pain or other symptoms, there are two ways to immediately improve blood flow — angioplasty, usually with the placement of a wire-mesh stent, or bypass artery surgery (see illustration). If the blockage is simple and confined to a single artery, angioplasty is often a good choice. It is quick and effective, and since it doesn’t require opening the chest, the recovery time is short. For more severe or complicated problems, doctors have traditionally relied on bypass surgery. This has long been the approach taken for the left main coronary artery before it divides into two branches (see illustration). This is a serious problem because the left main coronary artery nourishes such a wide expanse of heart muscle. Bypass surgery has also traditionally been performed for three-vessel disease, which covers simultaneous blockages in the left anterior descending artery, the circumflex artery, and the right coronary artery.
Advances in angioplasty, especially in stent design, have prompted interventional cardiologists (the doctors who do angioplasty) to push the envelope in the types of coronary disease (CAD) they tackle. Some have been using angioplasty and stents for left main coronary artery disease and three-vessel disease. How well angioplasty works in these situations is controversial. Earlier trials suggested that bypass surgery was superior for these complex cases, but most of the trials were done before the advent of the latest generation of artery-opening stents. That gap has been temporarily plugged by the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) trial. (Percutaneous coronary intervention or PCI is medicalese for angioplasty, with percutaneous meaning through the skin.) Results of the SYNTAX trial were published in the March 5, 2009 issue of the New England Journal of Medicine (NEJM).
You Have A Choice
The study concluded that surgery was still the standard of care for patients with three blocked coronary arteries or left main coronary artery disease. The main lesson from SYNTAX, however, is not that surgery or stenting is better for left main or three-vessel coronary artery disease. Instead, it is that you have a choice, depending on the anatomy of your heart, the number and location of your blockages, and your other health issues.
“There are certain patients who would be better served by stents and others who do better with surgery,” says Joseph Sabik, MD, chairman of thoracic and cardiovascular surgery at the Cleveland Clinic. “What has to happen is patients have to be informed of the risks and benefits of each procedure so they can make an informed decision.”
Do You Need Revascularization?
In January 2009, a panel of experts unveiled the criteria for using revascularization (angioplasty or bypass). Among these are:
• Revascularization is appropriate if the expected improvement in survival, symptoms, function, and/or quality of life outweigh the potential risks.
• Revascularization would be inappropriate in a patient with plaque accumulation in one or two arteries and little muscle at risk, who experienced symptoms only during strenuous exercise, and was not taking medications.
• Conversely, revascularization would be appropriate if a similar patient had severe symptoms despite taking the best available heart medication.
If you’re considering revascularization, here are some questions to ask your cardiologist or surgeon:
• Which coronary artery is blocked, and is the location of the blockage more suitable for stenting or surgery?
• Will this procedure help me feel better? Live longer?
• Is medical therapy as effective in terms of helping me feel better and live longer?
• If I have a stent implanted, will I need bypass surgery three to five years from now?
• If I choose surgery, which bypass grafts are you going to use? (Arteries from the chest and the radial artery in the arm may last longer than the saphenous veins from the legs.)
• How much experience do you have in my procedure of choice?
Making The Right Choice
Angioplasty is less expensive and allows for a faster recovery, and advances in stent technology have reduced the rate of renarrowing (restenosis) of the blocked arteries. On the downside, angioplasty patients must take medications such as clopidogrel (Plavix), which prevents clots from forming in the stent but also increases the risk of bleeding.
Bypass surgery is painful and requires longer hospital stay and several months of recovery. “The benefit, though, is that it’s our best long-term solution to these problems,” Dr. Sabik says. Bypass surgery is becoming less invasive, he adds, and for many patients, the operation can now be performed through small incisions in the side of the chest rather than requiring the sternum (breastbone) to be split.
Although SYNTAX and other studies suggest that surgery may be best for patients with severe CAD, Dr. Sabik says that may not be the case for every patient, especially those with co-morbid conditions who aren’t healthy enough for surgery. Angioplasty also may be more appropriate for patients with single-vessel CAD, particularly involving the right coronary or circumflex arteries, he adds.
He recommends that patients meet with cardiologists and surgeons to weigh their options and decide on the best course of action. “You have to take each patient and look at them as an individual, look at what you’re trying to accomplish, and make sure the treatment is right for them, considering who they are and what problems they have,” Dr. Sabik elaborates.
Complementary, Not Competitve
The future of revascularization may lie in a combination approach. For instance, surgery might be done to bypass blocked left main coronary artery, while a stent might be used to open a blocked right coronary artery. These hybrid procedures allow people to reap the benefits of both approaches.
“We have to think about these two procedures not so much as competitive anymore but as complementary,” he says. “The best approach might be a combination of what the cardiologists do and what the surgeons do, taking the best of both and treating the patient as an individual.”
• Reference: The Syntax Trial, New England Journal of Medicine, March 5, 2009
• Sources: “Trial renews surgery vs. stent debate,” May 2009
Harvard Health Publications
“Which option is best to reopen blocked coronary arteries?”
Cleveland Clinic Health Advisor, July 2009
