ACC: Sirolimus stent helps combat left main coronary artery stenosis
While recent data have shown that PCI may be safe and effective in patients with unprotected left main coronary artery stenosis (ULMCA), there is no relative data comparing PCI with CABG.
To bolster these data, researchers from the Asan Medical Center in Seoul, South Korea, enrolled 600 patients in the PRECOMBAT (Premier of Randomized Comparison of Bypass Surgery versus Angioplasty using Sirolimus-Eluting Stent in Patients with Left Main Coronary Artery Disease) trial to compare PCI with a sirolimus-eluting stent (n=300) and CABG (n=300) in patients with ULMCA stenosis of over 50 percent.
Patients who underwent PCI received a sirolimus (Cypher, Cordis) stent and all recieved off- or on-pump surgery at the operator’s discretion and received dual-antiplatelet therapy for at least six months post-PCI, said lead author of PRECOMBAT, Seung-Jung Park, MD, PhD.
Park et al conducted follow-up at 30 days and, six, nine and 12 months by means of a telephone interview. All patients underwent routine angiographic follow-up eight to 10 months after PCI and ischemia-guided angiographic follow-up after CABG.
The researchers used major adverse cardiac or cerebrovascular events (MACCE) including death, MI, stroke and ischemia-driven target vessel revascularization (TVR) as the study’s primary endpoint. At one year, these rates were 8.7 percent for PCI and 6.7 percent for CABG. At two years, these rates were reported to be 12.2 percent vs. 8.1 percent, respectively.
Additionally, the researchers found that the rates of a composite of death, MI or stroke occurred at a rate of 4 percent for CABG and 3.3 percent for PCI at one year. These rates at two years were 4.7 percent vs. 4.4 percent. Rates of cardiac death were similar and were reported to be 2 percent vs. 1 percent for CABG and PCI at one year.
While the aforementioned event rates were similar, the rates of ischemia-driven TVR at 24 months were greater in the patients who underwent PCI compared with those who underwent CABG, 9 percent vs. 4.2 percent.
However, Park noted that “although angioplasty did have a higher risk of TVR, this efficacy endpoint does not have a direct association with mortality and thus has a less significant implication than the safety outcomes. Therefore, we can conclude that angioplasty can be a feasible alternative to CABG surgery.”
Park concluded that the trial suggests that performing PCI with a sirolimus-eluting stent is a viable option to CABG and MACCE rates for ULMCA stenosis patients were similar.
Gregg W. Stone, MD, the panel’s co-chair, said that the PRECOMBAT trial data “follow on the heels of the larger SYNTAX study, which studied the Taxus paclitaxel-eluting stent vs. bypass surgery in left main patients.” The positive outcomes of the left main cohort within the trial led to left main PCI becoming a Class IIb in the U.S., and either Class IIa or IIb in Europe.
Panelist James B. McClurken, MD, said, “It is clear that unprotected left main coronary artery disease can now be treated interventionally and what we are learning is that there are subgroups that clearly are at greater risk for MACE down the line.”
McClurkin noted that it will be important to include TVR as a major adverse cardiac event and said however, that it is clear that the treatment of less complex lesions had equal outcomes during surgery or intervention after two years. In addition, McClurkin offered that use of total arterial revascularization can help improve outcomes.
And while an important part of patient selection may be SYNTAX scores, an equally important factor is operator experience.
“There are patients with left main coronary disease that can be treated percutanteously but we don’t know which groups or subgroup,” offered panelist Bernard J. Gersh, MD. “SYNTAX data show that in those with very complex disease when it looks as though there is a real benefit from surgery, PCI shouldn’t be done.” However, there are other subsets where patients clearly benefit from PCI and a group in-between where selection should be individualized. More data are coming, and that is what we will need to tell patients, he concluded.