A major new study on 1,800 patients with heart disease has found that coronary artery bypass grafts (CABG) are superior to angioplasty and stenting in the long run. New findings presented at a Geneva meeting of the European Assn. for Cardio-Thoracic Surgery show that patients who received angioplasty and a stent to hold arteries open were 28% more likely to suffer from a major adverse cardiovascular event, such as stroke or heart attack, were 46% more likely to require a second procedure to reopen the blocked blood vessels and were 22% more likley to die.
Given that cardiovascular surgeons have suspected the benefits of bypass for a long time, the question is why angioplasty is so much more popular. An estimated 1.3 million Americans will undergo angioplasty this year, compared with 448,000 who will have CABG, according to the National Center for Health Statistics. True, angioplasty is cheaper than bypass -- at least initially -- and is easier on the patient, who is typically hospitalized only overnight and can go back to work in a couple of days. But given the benefits of CABG, why do so many opt for angioplasty?
One reason is convenience. Many arterial blockages are discovered through angiography, in which a catheter is inserted through a blood vessel in the groin and threaded to the site of the suspected blockage. When a blackage is discovered, said Dr. Stephen Lahey, a cardiac surgeon at Maimonides Medical Center in Brooklyn and a professor of medicine at SUNY Downstate, the patient is typically asked whether the cardiologist should just go ahead and perform angioplasty because the patient is already on the table. "The natural tendency is to opt for something that is [more convenient], far less invasive and doesn't hurt as much," he said. "But is that the right thing, or good for the patient? Sometimes, we have to say I know you want [angioplasty], but that really isn't the right thing for you."
That situation "takes away the opportunity for informed consent," added Dr. Michael J. Mack, medical director of cardiovascular services and director of transplantation for Medical City Dallas Hospital, a co-author of the new report. "The patient is lying on the table, recommendations are being made, and there is no real opportunity to gather all the facts. There is now a trend toward stopping, having an objective conversation with the patient, the cardiologist and a surgeon."
Moreover, added Dr. John Conte, associate director of the division of cardiac surgery at Johns Hopkins Hospital in Baltimore, the cardiologist will often say, "If you don't do well, we can always give you surgery later." But, he added, "if people will do better with surgery the first time, why put them through the added risk?" A major conclusion of the new study is that, before angiography, the patient should meet with a team containing both a cardiologist and a surgeon who will present them with all the pros and cons of both procedures. "That paradigm [of a team approach] is already established in oncology. Why can't we do it in cardiology.... It's absolutely amazing that the federal government and payers don't insist on it."
The final question, and perhaps the easiest to answer, is why bypass proved better. "Coronary bypass treats most of the current and future blockages of a vessel. Stenting treats a single lesion," said Dr. Richard Guyton, chief of cardiothoracic surgery at the Emory University School of Medicine. "If there is one severe lesion [blockage] and five emerging lesions, stenting treats the existing lesion and the emerging ones are still there." Because bypass replaces a much longer section of artery, it takes care of the emerging lesions as well. Most recurrent heart attacks are not caused by a re-blockage at the site of the angioplasty, he said, but by the sudden closure of an artery caused by a ruptured plaque from another site. "That's the reason there is a difference in outcome between the two procedures."
All the researchers agreed, however, that there was one time when angioplasty was not only preferred but absolutely necessary -- when a patient had a heart attack caused by the sudden blockage of an artery. In such situations, time is of the essence, and angioplasty is the fastest way to reopen the artery and save the patient's life.
-- Thomas H. Maugh II / Los Angeles Times