Cardiovascular diseases are killing more and more people around the world, striking rich and poor alike. Those who survive a heart attack or stroke often need to take long-term medical treatment. If you have ever had a heart attack or stroke, or had to care for someone who has, you will know that these diseases can seriously affect the life of both the patient and his or her family.
Heart attacks can also be caused by a blood clot that gets stuck in a narrow part of an artery to the heart. Clots are more likely to form where atherosclerosis has made an artery more narrow.It occurs when fat , cholesterol , and other substances build up in the walls of arteries and form hard substances called plaque.Disease develops when a combination of fatty material, calcium, and scar tissue (plaque) builds up in the arteries that supply the heart with blood. Through these arteries, called the coronary arteries, the heart muscle (myocardium) gets the oxygen and other nutrients it needs to pump blood.
Eventually, the plaque deposits can make the artery less flexible. This makes it harder for blood to flow. If blood flow in the arteries leading to the heart is reduced, chest pain can occur. Plaques can also break apart, causing pieces of material to move through the artery. This is a common cause of heart attack and stroke.Clots may further reduce blood flow, causing severe pain (angina), or even block it all together.
Treatment aims to balance blood supply to the heart with heart oxygen demand, and prevent worsening of coronary heart disease. Each year, more than 600,000 Americans have angioplasty procedures to open clogged arteries near their hearts, and treat or prevent a heart attack.In an increasing number of health systems, patients are offered expensive therapies such as coronary bypass surgery or angioplasty in an effort to open or bypass vessels that have become so narrow that they are unable to supply sufficient oxygen to the heart.
During the procedure, the catheter is inserted into a blood vessel either at the wrist, elbow or groin. The catheter is pushed through the blood vessel to the blockage in the artery. Inflating a balloon at the tip of the catheter stretches the narrowed artery. The stretching of the artery greatly improves blood flow through the artery. Often a metal device called a stent is left in the artery to improve chances that the blood vessel will stay open. Angioplasty can open up the artery that is blocked. This may relieve your symptoms because more oxygen will be able to go through the artery to your tissues.
Angioplasty and stent placement is a common treatment strategy for coronary artery disease and chronic stable angina. Chronic stable angina is a form of chest pain that happens when your heart is working harder and needs more oxygen, such as during exercise. The pain goes away when you rest. Your narrowed arteries can be the cause of this form of angina.
The COURAGE trial found that in people with chronic stable angina, having angioplasty and stent placement combined with medical therapy (drug treatment and lifestyle changes) did not prevent any additional deaths or heart attacks compared with medical therapy alone. Medical therapy is defined as diet and lifestyle changes along with medications including statins, anti-clotting drugs like aspirin and high blood pressure medications like angiotensin-converting enzyme (ACE) inhibitors and beta blockers.
This study suggests that if you have chronic stable angina, you may not need angioplasty and stenting immediately. It may be just as effective to try drug treatment and adopt a healthy lifestyle and diet.
Study finds that aggressive drug therapy appears to be just as good as angioplasty for patients with stable heart disease.
"This is really good news for patients," said study lead author Dr. William E. Boden, a professor of medicine and public health at the University at Buffalo School of Medicine and Biomedical Sciences. "We have more treatment options for patients than we thought we did."
There has been a belief that patients with chronic stable heart disease need to have either an angioplasty or heart bypass surgery, Boden said. "There has been an unproven assumption that patients must proceed to some type of revascularization procedure," he said.
Patients with stable heart disease make up about three-quarters of all the patients who undergo angioplasty and receive stents in the United States, Boden noted. Angioplasty is a medical procedure that uses a balloon to open narrowed or clogged blood vessels of the heart. Usually, during the procedure a stent -- a wire mesh tube -- is placed in the vessel to keep it open.
"What the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial tells us is that optimal medical [drug] therapy, when combined with lifestyle changes, appears to be the equal of angioplasty and optimal medical therapy combined," Boden said.
The study results were presented Monday at the American College of Cardiology's annual meeting, in New Orleans, and will also be published in the April 12 issue of the New England Journal of Medicine.
For the study, the COURAGE group randomly assigned almost 2,300 patients with stable but significant heart disease to one of two treatment regimens at 50 U.S. and Canadian treatment centers. The first group received drug therapy alone, while the second group received the drug therapy plus angioplasty. Among the latter group, 94 percent received at least one stent.
During a follow-up from two to seven years, the researchers looked for incidence of heart attack or death. They found that 211 people (19 percent) in the angioplasty group had died or had a heart attack, compared to 202 people (18.5 percent) in the group that only received drug treatment.
There were also no significant differences between patients who had angioplasty and those who had drug therapy alone in rates of death, heart attack, stroke or hospitalization for acute coronary syndrome (20.0 percent vs. 19.5 percent) or heart attack alone (13.2 percent vs. 12.3 percent).
The only benefit of angioplasty, according to Boden's team, was that it reduced chest pain over the long-term compared with drug therapy alone.
About 30 percent of the patients who received drug therapy alone did eventually undergo angioplasty because their symptoms couldn't be managed with drugs alone. In addition, about 21 percent of the patients who received stents needed to have another procedure, Boden said.
Based on these findings, Boden believes that drug therapy for patients with stable heart disease should be tried as first-line treatment. "I am hopeful that physicians will have the courage to consider medical therapy as a viable option," he said.
However, Boden doesn't think initial use of drug therapy alone will reduce the number of angioplasties being performed. "What it may do is delay the timing of when angioplasty gets done," he said.
"As an initial strategy, medical therapy is a defendable approach," Boden added. "We should no longer consider it to be putting patients in harm's way, or thinking of it as an inferior treatment strategy."
The COURAGE trial was sponsored by the U.S. Department of Veterans Affairs Office of Research and Development and the Canadian Institutes of Health Research, and research grants from a number of top pharmaceutical companies.
The makers of stents and physicians who support their use were critical of the study, saying its design left it "doomed to fail," according to published reports.
Addressing some of the critics' concerns, including the fact that the trial didn't include drug-coated stents, Boden told a press conference at the meeting Monday afternoon that these stents were not available at the start of the trial.
"We would have loved to use them," he said. "But there is not a shred of scientific evidence to support the fact that drug-eluting stents are superior to bare-metal stents, in terms of reducing death and heart attack. Using drug-eluting stents would have no difference in the primary endpoint. It might have resulted in fewer revascularizations."
One expert agrees that drug therapy is a viable initial option for most patients with stable heart disease.
"Intensive medical therapy to dramatically reduce risk factors, such as reducing bad cholesterol and raising the good cholesterol, was associated with outcomes that were similar when that same therapy was used and angioplasty was added," said Dr. Judith S. Hochman, a professor of cardiology at New York University School of Medicine, and author of an accompanying editorial in the journal.
"There was no additional benefit from angioplasty, beyond what has evolved to be excellent medical therapy," she added.
Hochman said it was striking that many patients had reductions in chest pain on drug therapy alone. "Many patients became angina-free," she said. "Although angioplasty was better at relieving symptoms, it wasn't better in preventing death or heart attack."
Hochman noted, however, that if a person is having a heart attack, angioplasty remains the appropriate treatment. "If you are having a high-risk unstable syndrome, angioplasty is very effective at reducing the chance of dying," she said.
But, for patients with stable heart disease, Hochman believes the first approach to care should be medications. "A trial of intensive medical therapy without angioplasty, to see how the symptoms respond, is what's indicated," she said.
Angioplasty should be reserved for patients who have continuing symptoms, Hochman said. "If you have too much angina to do the activities you want to do, despite a trial of intensive medical therapy, then angioplasty is a good option," she said.
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