Considerable differences in practice patterns are not lost on the major professional cardiology groups. In an effort to give practitioners some type of baseline for when it is appropriate to do any procedure at all—be it bypass surgery or an angioplasty and stent—six of the major groups put out a consensus document in January that addresses about 180 of the most common types of patient situations based on severity of their angina symptoms. The aim was not to dictate which procedure to use in a given patient or offer treatment guidelines but rather to suggest whether doing a procedure to increase blood flow in the heart would be "appropriate" or "inappropriate" or "uncertain." Gregory Dehmer, one of the document's lead writers and an interventional cardiologist and professor of medicine at Texas A&M College of Medicine, says that, in the future, "I'm going to always ask [myself], 'Would this be appropriate according to the criteria?' and if not, but I feel it needs to be done, I'm going to have to ask myself, 'Why am I doing it?' " Patients should be aware that the document exists, he says, and consider it a starting point for discussions with their doctor.
Heart patients must also know that theirs is not simply a plumbing problem. Neither an angioplasty plus stent insertion nor a bypass procedure is typically recommended unless the artery is at least 50 to 70 percent blocked. Opening smaller blockages with angioplasty or a stent can prompt the vessel to suddenly close up, and undergoing major surgery is not typically advised for early-stage disease. Yet in the vast majority of cases, it's the rupturing of unstable plaque from arteries with less significant blockages—maybe closer to 20 percent—that causes a blood clot that triggers a heart attack. Therefore, using medications to stabilize these dangerous plaques is critical. On the other hand, while the larger blockages don't typically cause a heart attack, they do cause angina, which may be predictable and not very serious but also can be unpredictable and cause crushing pain. Patients are well advised to spend time considering how tolerable their symptoms are, since undergoing either angioplasty or bypass surgery could trigger a heart attack. You should undergo angioplasty, get a stent, or have a bypass, advises Wong, only if you suffer from severe angina even after time on the right medications, an improved diet, and a regular exercise program—and off cigarettes.
Surgery becomes the clear option, says cardiac surgeon Guyton, in very complex disease—large blockages in three vessels, say, or in the critical left main coronary artery—where the heart muscle is compromised by getting considerably decreased blood flow. Results of a study presented at the 2008 European Society of Cardiology Congress found that patients with advanced disease—with multivessel blockages, say—were better off getting bypass surgery than an angioplasty and stent. Twelve percent of patients who had bypass experienced death, heart attack, stroke, or the need for a repeat procedure, compared with nearly 18 percent who had angioplasty or a stent.
However, according to the new appropriateness document, angioplasty and stent placement in a patient with three-vessel disease and diabetes, for example, was deemed neither "appropriate" nor "inappropriate" but "uncertain." Bypass surgery in such a patient is considered "appropriate." Certainly, the less-invasive procedure may be the best option if the person is too frail to withstand major open-heart surgery. On the other hand, if they are unaware of all their options, patients who are sturdy enough to undergo the surgery may run the risk of being swayed in the direction of the less-invasive option, which in the long run might not be as effective.
To be sure, going through bypass surgery is no small feat. A person who gets a stent may be up and mobile in days, but bypass patients can take weeks or months to feel like themselves again. And the surgery also carries a long-term risk of cognitive loss or depression, possibly related to having relied on a machine to pump oxygenated blood to the organs while the heart is stopped during the hours-long surgery. Another trade-off to consider is the likelihood of needing further procedures. With bypass, about 3 out of 100 patients will require another procedure within the first year. Depending on the type of stent a patient gets, somewhere between 9 and 18 out of 100 patients will need another procedure within the first year.