An electrocardiogram, one of the tools used to diagnose heart health.
Cardiologists meeting Monday in New Orleans are discussing a study that says one of the most frequently used treatments for heart disease is no better at preventing heart attacks or deaths than a regimen of drugs and healthy lifestyles. The treatment is the artery-clearing procedure called angioplasty, followed by insertion of tiny tubes called stents to keep the arteries open.
There's no question that angioplasty actually saves lives when it's done while somebody's having a heart attack or having chest pain at rest. But now some leading cardiologists are calling the study a blockbuster, because it's the first study to test rigorously the use of angioplasty and stents for people with what doctors call stable coronary disease, i.e., they may have chest pain, but only on exertion.
Researchers randomly assigned 2,300 patients with stable heart disease to two groups. Both were given drugs to control their cholesterol and blood pressure and minimize blood clots, and all patients were counseled to lose weight, exercise and stop smoking. But one group also was given angioplasty and stents to open up coronary blockages.
"When all was said and done, the results did not support additional benefit of angioplasty and coronary stents when added to a regimen of medical therapy and lifestyle intervention," said Dr. William Boden of Buffalo General Hospital, who presented the results Monday at the American College of Cardiology meeting in New Orleans.
That may come as a surprise to many heart patients. About 80,000 get angioplasty and stents every month, almost a million each year. It's not clear how many have stable coronary disease. Some experts estimate that 40 percent of heart patients have stable coronary disease, others say as many as 85 percent fall into that category.
Many patients undergo the procedure to relieve their chest pain. As expected, the new study showed that those given angioplasty did have less chest pain, especially in the first year after the procedure.
But Boden says this angioplasty advantage faded over the nearly five years of the study, because drug treatment did better at controlling symptoms.
"We were rather surprised that it was as good as it was for alleviating chest discomfort," Boden said.
Dr. Steven Nissen, president of the American College of Cardiology, said that although the new study seems counterintuitive, it in fact supports new thinking about heart disease. The obvious buildups of cholesterol-laden plaques in coronary arteries aren't the truly dangerous ones.
"Most heart attacks do not occur because of a blood clot at the site with the worst narrowing in the coronary," Nissen said. "Most heart attacks occur at a site with relatively minor blockage in the coronary, and so the very sites where you put a stent are not the ones likely to cause the next heart attack or sudden death."
That's why clearing the obvious blockages doesn't do what doctors hoped it would, Nissen said.
"Putting a stent in the most narrowed area in the artery doesn't really address the underlying problem," he said. "This cholesterol accumulation in the wall of the artery is everywhere."
Many cardiologists who make their living doing angioplasties and implanting stents dismiss the new study. They say they no longer claim that the procedure saves lives or prevents heart attacks in patients with stable coronary disease.
They also say the study doesn't prove that drug therapy is nearly as good at relieving chest pain.
Texas cardiologist Dr. Gregory Dehmer leads the Society for Cardiovascular Angiography and Interventions, a national group of cardiologists who specialize in angioplasty and stenting. He says patients who are told they have a blocked coronary artery believe they need the procedure.
"One of the most common questions a patient will ask is: 'Doc, what's [the] chance I'm going to have a heart attack?' For years and years and years, patients would think, 'If I have a 90 percent blockage and my next-door neighbor has a 50 percent blockage, my chance of heart attack must be worse.' We now know that's not true," Dehmer said.
It's not clear whether the new study will reduce the number of angioplasty-and-stent procedures. And it doesn't address another recent question about stents — an indication that stents impregnated with drugs are linked to heart attacks. Those stents weren't used in this study.