Angioplasty Doesn't Prevent Heart Attacks

Angioplasty also known as percutaneous coronary intervention (PCI) has become a routine procedure for clogged arteries in a stable patient with coronary artery disease (CAD) despite the fact that there is no good evidence it helps prevent heart attacks and cardiovascular disease (CVD) mortality. In fact several studies suggest it may even modestly increase the risk of having and dying from CVD.

In 2004, cardiologists performed well over a million PCI procedures usually leaving behind stents to prop open narrowed coronary arteries and improve blood flow to the heart muscle. Certainly PCI appears to improve blood flow through narrowed coronary arteries and reduce angina and improve exercise tolerance in the short term. However, many people who undergo PCI are led to believe PCI will also cut their risk of having or dying from a heart attack. For many years it was assumed that PCI helped prevent heart attacks and reduced deaths from CAD even though what little research had been done indicated PCI was of no benefit for preventing CVD events or deaths No one questions the use of PCI when someone is in the midst of a heart attack when restoring blood flow to the heart by opening an acutely blocked coronary artery can lessen the damage to the heart. However, about 85% of all PCI are done on patients with stable atherosclerotic plaques and for them it does little or no good. This is why current treatment guidelines do not call for PCI in stable CAD patients, but rather call for a healthier diet, smoking cessation, exercise, and aggressive use of drugs to help control blood lipids and other cardiovascular disease (CVD) risk factors and reduce angina. This is called optimal medical therapy (OMT). A large randomized clinical trial at 50 hospitals examined the impact of PCI with OMT or OMT alone on patients with stable CAD. Over 2000 patients were randomly assigned to one of these two interventions and then followed for an average of 4.6 years. Primary events included deaths from any cause and nonfatal heart attacks. There were 211 primary events in the PCI group and 202 primary events in those treated only with OMT. While not statistically significant, the PCI group had more CVD events than the OMT only group. The authors of this study conclude: “As an initial management strategy in patients with stable coronary artery disease, PCI did not reduce the risk of death, myocardial infarction, or other major cardiovascular even when added to optimal medical therapy.”1 The only modest benefit of PCI vs. OMT alone was a modest reduction of patients who still experienced angina. At 1 year 66% of those who had the PCI were free of angina compared to 58% in the OMT only group. By 5 years even this modest reduction in the incidence of angina was no longer statistically significant. In marked contrast to the disappointing results from PCI, a study examining a more aggressive dietary approach using a very low fat, near vegetarian (VLFNV) diet added to conventional medical therapy markedly reduced the risk of dying from or suffering a CVD event. More importantly those following the VLFNV diet compared to those treated less aggressively experienced more than a 4-fold reduction in the risk of dying over the next 5 years. Data for this study shown in the figure above.2Bottom Line: While the financial incentives are large for aggressively promoting PCI for patients who have stable CAD, the benefits are minimal at best. Perhaps it is time health insurance companies, Medicare, and Medicaid start paying for more aggressive medical nutrition therapy and stop paying for the 85% of PCI done in stable patients. By James J. Kenney, PhD, RD, FACN References: 1. N Engl J Med 2007;356:1503-16 2. J Am Coll Cardiol 2003;41:263-72