Bypass Surgery Compared To Stent Procedure
A major long-term study of patients treated for coronary artery disease finds that those who undergo bypass surgeries do much better than those who have an artery-widening procedure involving a stent, according to the New England Journal of Medicine.
A stent is a wire-mesh tube used to prop open blocked vessels.
The study of more than 37,000 people treated for coronary artery disease in New York state between 1997 and 2000 found the death rate for patients with blockages in three coronary arteries to be a third lower for those who underwent bypass surgery than those receiving stents.
The death rate for people with two blocked arteries was 24 percent lower with bypass surgery, the researchers added. And they noted that 7.8 percent of arteries receiving stents closed again within three years, compared to just 0.3 percent of arteries operated on in bypass patients.
The findings challenge the results of the carefully controlled, randomized trials that have long been regarded as the gold standard in this area of research, says lead investigator Edward L. Hannan, Ph.D., chairman of the department of health policy management and behavior at the University of Albany, N.Y.
"The results are essentially different from those of the controlled trials," Dr. Hannan says. "For the most part, the randomized trials have not found significant differences in outcome between the two procedures."
Several reasons might explain the difference between the results shown in the new study and those of the previous trials, Dr. Hannan says.
"First, the [original] trials are based on a very small number of patients, so it takes huge differences to come up with a statistically significant difference," he says.
On the other hand, Dr. Hannan notes, his team's study involved "very large numbers. Second, randomized trials are very restrictive, excluding a lot of patients for a variety of reasons, so what is reported in the trials is not reflective of what goes on in the real world.
"Also, patients in the trials are followed very carefully. If the cardiologist finds chest pains, the patient is immediately given treatment to avert problems. In the real world, you don't have people who are following you like that," he adds.
According to Dr. Hannan, these fundamental differences reveal a "downside of clinical trials that a lot of people don't admit to."
But Dr. Bernard J. Gersh, author of an accompanying editorial in the journal and a professor of medicine at the Mayo Clinic College of Medicine, says what happens in the real world is cardiologists use their clinical judgment to select the best treatment, based on a patient's condition.
"What we find in this real-world study is that sicker patients appear to benefit more from surgery, while the less-sick group does as well with PCI [artery-widening stents] as with surgery," Dr. Gersh says.
The current study shows that evidence from controlled trials "goes hand in hand with clinical judgment," he says. In other words, "[Each] physician needs to take this evidence and apply it to the individual patient."
Always consult your physician for more information.
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Behavior modification techniques such as exercise and stress management can not only reduce the levels of depression and distress in heart patients, but can also improve physiological markers of cardiovascular health, according to a study reported in the Journal of the American Medical Association.
According to a Duke Medical Center research team, this may be the first randomized trial to demonstrate that a non-pharmaceutical approach can have positive effects on physiological determinants of cardiovascular health. This includes blood flow to the heart, the responsiveness of the lining of blood vessels, and the ability of the cardiovascular system to regulate surges in blood pressure.
"While studies have shown that psychosocial factors such as depression, stress, and anxiety place heart patients at a much greater risk of suffering future cardiac events or dying, few have looked at the effects of modifying psychosocial factors," says Duke medical psychologist James Blumenthal, Ph.D., lead author of the Duke study.
"Our results suggest that exercise and stress management training offer considerable promise for patients with heart disease by not only improving psychosocial functioning and reactions to mental and physical stressors, but also by modifying important bio-markers of risk that may translate into improved clinical outcomes," he says.
The Duke trial enrolled 134 patients with stable heart disease and randomized them to one of three groups - exercise, stress management, or standard medical therapy.
Patients randomized to the exercise group participated in 35 minutes of supervised aerobic exercise training three times a week for 16 weeks. Those in the stress management arm received 16 weekly 1.5-hour classes designed to help patients recognize the sources of stress in their everyday lives and to teach them strategies to respond more adaptively to those stresses.
Patients enrolled had stable heart disease, meaning they did not experience chest pain while at rest, and exhibited evidence of myocardial ischemia, or reduced blood flow to the heart, during exercise. All participants underwent a battery of psychological and physiological testing before randomization, which was repeated four months later.
One of the physiological markers studied was the endothelium, which forms the inner lining of the blood vessels and controls how the vessels reacted to changes in blood flow and pressure.
The researchers took ultrasound images of the brachial artery of the arm before and after a tourniquet was applied and released to determine how the vessels responded. Healthy arteries will dilate to accommodate the increased blood flow, while diseased arteries are less responsive, the researchers says.
The researchers also found that patients who received exercise training or stress management had improved baroreflex sensitivity, a phenomenon by which receptors located along the walls of blood vessels respond to changes in blood pressure. These receptors are connected to the heart by nerves, which carry the message to pump faster or slower in response to pressure changes.
Additionally, the researchers measured changes in the left ventricle - one of the two pumping chambers of the heart - during periods of both mental and physical stress.
Always consult your physician for more information.
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