Am Fam Physician. 2006;73(1):148-150
Percutaneous coronary intervention (PCI) has been shown to have significant benefits in the treatment of unstable coronary artery disease (CAD); however, its role in the management of stable CAD remains controversial. Although PCI of stenotic coronary arteries relieves symptoms of angina more effectively than medical management alone, it is uncertain whether PCI is superior at preventing “hard” clinical outcomes such as death, myocardial infarction, and the need for subsequent revascularization. To answer this question, Katritsis and Ioannidis performed a meta-analysis of randomized controlled trials that compared PCI to medical management in patients with chronic stable CAD.
Eligible trials included patients with CAD of one or more vessels documented by angiography. Trials were excluded if they contained patients who had experienced an acute coronary syndrome within one week of study entry, or if the initial intervention was coronary artery bypass grafting rather than PCI. Eleven trials with a total of 2,950 participants enrolled between 1987 and 2001 were included in the meta-analysis. Almost all participants were men. In eight of 11 trials, greater than 40 percent of all participants had had a previous myocardial infarction. Only six of the trials used stents following PCI; none of these stents were drug-eluting.
Overall, there was no statistically significant difference observed in the occurrence of death, new myocardial infarction, or need for subsequent revascularization between the PCI and medical therapy groups. The availability of stents did not change these results. The six trials with two years of follow-up or less showed a trend toward an increased risk of myocardial infarction in PCI-treated patients.
The authors conclude that PCI has no clear advantage over medical therapy for chronic stable CAD for the “hard” clinical outcomes studied. They caution that this conclusion may not reflect recent advances in medical management (e.g., the lowering of treatment thresholds for hypercholesterolemia) or the development of drug-eluting stents that remain viable longer than bare-metal stents. Nonetheless, they assert that in the absence of new data, physicians should reconsider the practice of performing PCI routinely in patients with stable CAD.
editor’s note: In many areas of the United States, it is commonplace for a patient with symptoms of stable angina and a “positive” stress test result to undergo coronary angiography and PCI. Debates in recent years have largely revolved around what type of stent to use rather than whether PCI is indicated at all. The obvious objection to the conclusions of this meta-analysis is that none of the included trials studied drug-eluting stents. However, a separate meta-analysis recently conducted by Katritsis and colleagues1 found no difference in clinical outcomes between drug-eluting and bare-metal stents after one year of follow-up; the advantage of the new stents appears to be a decreased need for repeat PCI. Given evidence that primary care physicians substantially undertreat patients with chronic stable angina,2 the higher priority seems to be making sure we maximize medical therapy rather than referring these patients for an intervention with no apparent additional benefit.—k.w.l.