Newly released results of a trial that compares the impact of coronary-artery bypass graft surgery (CABG) and percutaneous coronary intervention (PCI) show that patients who underwent the former have fewer adverse effects than those who underwent the latter.
The findings could give patients a reason to choose CABG over drug-eluting stent (DES) procedures.
The SYNTAX trial evaluated 1,800 patients throughout the course of a year in an international, multicenter, randomized controlled comparison of CABG, vs. PCI with drug-eluting stents. All of the patients suffered from left main or three-vessel coronary artery disease. In all there were 85 sites throughout 17 countries in Europe.
Patient groups had a far more complex anatomy and advanced disease than those studied in prior drug-eluting stent clinical trials.
The trial was sponsored by Boston Scientific (Natick, Massachusetts).
The trial's principal investigators are Friedrich Mohr, MD, program director of the Heart Center/Cardiothoracic Surgery at the University of Leipzig (Germany) and Patrick Serruys, MD, PhD, chief of interventional cardiology at the Thoraxcenter of Erasmus University (Rotterdam, the Netherlands).
During that year, authors of the study were searching for four main adverse events death, myocardial infarction; stroke and revascularization. The authors looked for a combined end point of any one of the four events occurring within a year of randomization.
Results were presented in this week's online edition of The New England Journal of Medicine.
"The main bottom-line results of the study were that, at one year, about 12% of the CABG patients had had one of these four adverse events," said Dr. David Hillis, chairman of medicine at the University of Texas Health Science Center (San Antonio), during a webcast presented by NEJM."In contrast, 18% of the PCI patients had had one of those adverse events. So the bottom-line conclusion of the authors was that CABG remains the standard of care for patients with left main and three-vessel coronary artery disease."
The SYNTAX trial shows that major adverse cardiac or cerebrovascular events at a year were higher in the PCI group because of an increased rate of repeat revascularization.
But while that statement looks as though it could be the final nail in the coffin for PCI, a closer look at the data provides a bit of a boon for those still backing DES.
"If we look at the primary end point ... which was a combination of death, MI, stroke and the need for revascularization, if we drill down further, there was no difference between the two groups in death, MI and stroke at one year," Dr. Elizabeth Nabel, director of the National Heart, Lung and Blood Institute, said during NEJM's webcast."The primary end point was really driven by an increased need for revascularization in the PCI group. So that is an important distinction that we must remember. Furthermore, if we look at the complication rate, there was a 1.6% higher incidence of stroke in the CABG group, compared to the PCI group."
Specifically the rate of stroke was .6% for PCI compared to the 2.2% rate of occurrence in CABG.
This is the main focus of Boston Scientific, a developer of the Taxus Express2 Paclitaxel-Eluting Coronary Stent System, which was used during the trial.
"While CABG may still be the preferred treatment in many patients with complicated disease, some patients may now be candidates for a less-invasive alternative offered by stents," Ted Feldman, MD, director of the cardiac cath lab at NorthShore University HealthSystem (Evanston, Illinois) said in a release.
When pressed for further comment by Medical Device Daily, a spokesman for Boston Scientific declined, saying the company's position was covered in a press release it sent out yesterday.
The company first began enrolling patients in the SYNTAX trial in April 2005. It completed enrollment in April of 2007 (Medical Device Daily, April 27, 2007).
It can scarcely be considered a secret that stenting procedures (particularly drug eluting stents) have come under fire in the past few years. It all began right about the time Swedish doctors openly questioned the efficacy of DES and said that such procedures have a higher rate of death at the 2006 European Society of Cardiology (ESC; Sophia Antipolis, France) conference (MDD, Sept. 6, 2006).
The reports at the time indicated DES devices may increase the risk of potentially fatal blood clots in the form of late thrombosis. As a result, the worldwide use of DES went into a sharp decline, with sales going from $5.1 billion in 2005 to $3.9 billion in 2007, according to the Thomson Reuters agency Research Markets.
Whether or not the results of SYNTAX will continue to erode the DES market remains to be seen. What can immediately be gleaned from the study is that patients now have greater insight on which procedure they should undergo.
"I think that patients should have a chance to articulate their preferences and weigh the risk of stroke versus risk of other kinds of outcomes," said Dr. Tom Lee, an associate editor of NEJM."The SYNTAX trial will surely make those discussions much more informed and probably make them happen much more reliably."