No difference in mortality between stents and medical treatment
Patients with angina, ischaemia on functional testing (such as an exercise ECG) and flow-limiting coronary lesions at angiography will often be offered percutaneous coronary intervention (PCI). Nowadays this takes the form of intracoronary stenting. Stenting helps with symptoms, but does it reduce cardiac events and mortality in the long-term when compared with medical therapy alone?
The Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial set out to answer this question. The study recruited 2,287 patients from 50 North American centres between 1999 and 2004. The participants had classic angina and at least 80% proximal stenosis in one coronary artery, or 70% stenosis and baseline ECG evidence of ischaemia or ischaemia inducible by either treadmill or pharmacological stress. Patients with unstable symptoms, lesions unsuitable for PCI and significant left ventricular dysfunction (ejection fraction <30%) were excluded.
Patients were randomised to PCI and optimal medical therapy (1,149) or medical therapy alone (1,138). They were followed up for 2.5 to 7 years (median of 4.6 years). The primary end point was a composite of all-cause mortality and non-fatal MI.
There was no significant difference in the primary end point between the two groups, with 211 events in the PCI group and 202 events in the medical therapy group (hazard ratio 1.05; 95% confidence interval 0.87 to 1.27; P=0.62). Further analysis of individual outcomes showed no difference in rates of death, MI, stroke or hospitalisation for acute coronary syndromes between the two groups.
This trial supports the view that PCI in stable coronary disease is about relieving symptoms and not reducing mortality and future cardiac events. However, drug-eluting stents did not feature highly in this study (only 31 patients in the PCI group had drug-eluting stents), although the consensus view is that they would be unlikely to offer much of an advantage compared with the bare metal variety in this setting. It must also be remembered that the benefit of PCI in the acute setting is well established and that these results should in no way be extrapolated to that patient group.
Boden WE, O'Rourke RA, Koon TK et al. Optimal Medical Therapy with or without PCI for Stable Coronary Disease. New Engl J Med 2007;356:1503-1516Reviewer
Dr Peter Savill
GPSI Cardiology, Southampton