Percutaneous coronary implantation with a stent does not reduce mortality, nonfatal myocardial infarction, unplanned revascularization, or angina any better than does medical therapy alone in patients with stable coronary artery disease, according to a meta-analysis in the Feb. 27 issue of Archives of Internal Medicine.
The study findings "support current recommendations for instituting optimal medical therapy in patients with stable CAD [coronary artery disease] rather than proceeding directly to stent implantation," said Dr. Kathleen Stergiopoulos and Dr. David L. Brown of the division of cardiovascular medicine at Stony Brook (N.Y.) University.
In addition to these recommendations, several recent studies have clearly shown that initial percutaneous coronary implantation (PCI) is no better than medical therapy for nonacute CAD. Yet the findings have not been adopted into clinical practice. "Only 44% of patients are treated with optimal medical therapy prior to PCI, and approximately 50% of patients with an occluded infarct-related artery after an MI undergo PCI of that artery," Dr. Stergiopoulos and Dr. Brown noted.
One reason may be that a few recent meta-analyses reported that PCI did have advantages over medical therapy. But these meta-analyses included studies from the 1980s and early 1990s, before stent implantation was widespread and before many advancements in medical therapy had occurred.
"We therefore performed a systematic review and meta-analysis" that compared initial stent implantation plus medical therapy with a strategy of initial medical therapy alone to determine the effect of contemporary interventional and medical strategies on stable CAD. The meta-analysis included only prospective, randomized, clinical trials with a minimum follow-up of 1 year, in which stent implantation comprised at least half of the PCI procedures, and in which medical therapy included aspirin, beta-blockers, ACE inhibitors, and statins.
Eight studies fulfilled these inclusion criteria, involving 7,229 patients treated in 1997-2005. A total of 3,617 patients were randomly assigned to stent placement and 3,612 to medical therapy alone. The mean follow-up was 4.3 years.
There were 649 deaths during follow-up: 322 in the stent group, for a mortality of 8.9%, and 327 in the medical therapy group, for a mortality of 9.1%. These rates are not significantly different, the investigators reported (Arch. Intern. Med. 2012;172:312-9).
Nonfatal MI occurred in 323 patients who received stents (8.9%) and 291 who received medical therapy (8.1%), also a nonsignificant difference.
Unplanned revascularization was required in 774 subjects in the stent group (21.4%) and 1,049 of those in the medical therapy group (30.7%), another nonsignificant difference.
Information on angina status was available only for 4,122 study subjects. The rates of persistent angina were 29% with stent placement and 33% with medical therapy – again, a nonsignificant difference.
The findings of this meta-analysis "fail to support theories suggesting that PCI reduces mortality by improving myocardial blood flow or stabilizing vulnerable plaque in patients with angina, or by improving left ventricular remodeling or electrophysiologic stability in patients with an occluded artery following MI," the investigators said.
Their results also suggest that "up to 76% of patients with stable CAD can avoid PCI altogether if treated with optimal medical therapy, resulting in a lifetime savings of approximately $9,450 per patient in health care costs," they added.
The investigators reported no relevant financial disclosures.