Left main coronary artery disease: which stent type is preferred for off-label PCI?

July 29, 2007 By Benjamin A. Olenchock, M.D. Ph.D. [mailto:bolenchock@partners.org]

Melbourne, Australia In a study which is as interesting in its design as in its results, researchers have demonstrated that paclitaxel-eluting stents might be preferred to bare-metal stents for use in unprotected left-main coronary artery (LMCA) stenting.

Disease in the LMCA is an indication for coronary artery bypass grafting (CABG), as surgical revascularization has a proven mortality benefit. However, many patients and physicians would prefer a minimally invasive alternative to surgery. This has led to a great deal of interest in percutaneous intervention (PCI) and stenting for this indication, just as is done for lesions at other places in the coronary artery tree. There is a large trial underway in which outcomes for CABG vs. PCI are being compared, in order to decide whether PCI is a safe alternative for patients with LMCA disease.

In research published online in the Journal of the American College of Cardiology, researchers in Australia have already begun addressing the next question: if one is going to perform LMCA stenting, which stent type is preferred?

The majority of patients in the trial had stable angina. They randomized 103 patients to receive a bare-metal stent (BMS) or a paclitaxel-eluting stent (PES). Intravascular ultrasound and pre-treatment of the plaque with cutting-balloon dilatation was used to help modify the plaque prior to stent deployment. Their results were impressive. They were successful in all cases and experienced no in-hospital mortality. At 6-months follow-up, the major adverse event-free survival was 70% in the BMS group and 87% in the DES group (p = 0.036). The difference between the groups was mainly due to differences in need for revascularization and incidence of acute myocardial infarction, as there was only 1 cardiac-related death in the trial at 6 months.

This trial is of interest in part because it performed unprotected LMCA stenting on patients who mostly had stable angina. It is also of interest because their results were quite good. This research has provided support for this controversial procedure, and might help hasten us towards more minimally invasive approaches to LMCA disease. On the other hand, evidence is clearly in favor of CABG for this indication, and results of a direct comparison between PCI and CABG should be known prior to recommending PCI for LMCA stenting as routine practice. If we some day find out that PCI with stenting is safe for patients with LMCA disease, then maybe we should use a drug-eluting stent.

A Randomized Comparison of Paclitaxel-Eluting Stents Versus Bare-Metal Stents for Treatment of Unprotected Left Main Coronary Artery Stenosis In Press, Corrected Proof, Available online 23 July 2007, Andrejs Erglis, Inga Narbute, Indulis Kumsars, Sanda Jegere, Iveta Mintale, Ilja Zakke, Uldis Strazdins and Andris Saltups.