ESC: Bypass Surgery Trumps Stents for Complex Coronary Lesions
ByPeggy Peck, Executive Editor, MedPage Today
Published: September 01, 2008
ReviewedbyRobert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco
MUNICH, Sept. 1 -- Once again a percutaneous coronary intervention -- this time the paclitaxel-eluting Taxus stent -- was proven inferior to coronary artery bypass surgery (CABG), though by a narrower margin than in past head-to-head trials.
And in the final analysis, the "heart team" of the surgeons and interventional cardiologists conducting the SYNTAX (Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery) trial concluded that "CABG remains the only treatment option for at least one-third of patients screened."
So reported Friedrich W. Mohr, M.D., of the University of Leipzig in Leipzig, Germany, who was co-chairman of the international SYNTAX study, at the European Society of Cardiology meeting here.
Action Points
· Explain to interested patients that this trial investigated an off-label use of the Taxus stent, which is approved for single-vessel disease.
· Note that this study was published as an abstract and presented orally at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
Moreover, Dr. Mohr said, for patients who are not candidates for percutaneous intervention, "surgical results are excellent," while for patients who were not candidates for surgery, percutaneous intervention was "a viable option."
Patrick W. Serruys, M.D., Ph.D., of Erasmus University in Rotterdam, who co-chaired SYNTAX, said the numbers tell the tale, and the patients treated were sicker than in previous studies.
Previous head-to-head comparisons have also favored CABG, but in the past surgery bested intervention by double-digit margins, said Dr. Serruys.
At 12 months in SYNTAX, 17.8% of percutaneous intervention patients reached the combined endpoint -- myocardial infarction, stroke, death, or revascularizaton -- versus 12.1% of the CABG patients, a 5.7% difference that was statistically significant (P=0.0015).
And while the trial had a prespecified non-inferiority margin of 6.6%, "when the 95% confidence interval was calculated, the difference was 8.3% which did not meet the non-inferiority endpoint," Dr. Serruys said.
The rates for death, MI, and stroke were indistinguishable between the two arms, but the revascularization rate was 13.7% in the stent arm versus 5.9%, and that tipped the scale to favor surgery, Dr. Serruys said.
Although the trial recruited 3,075 "all-comer patients," only 1,800 met the criterion of being healthy enough to have either stenting or surgery. The other 1,275 patients were assigned to the registry arms -- 1,077 to CABG and 198 to stenting.
All patients had de novo disease and left-main disease could be "isolated, +1, +2, or + 3 vessels," Dr. Serruys said. The trial was conducted at 62 European centers and 23 U.S. sites.
In the registry trial, the differences were more dramatic -- at 12 months 20.4% of the stent patients had died, had an MI, or repeat revascularization.
The stroke rate was zero and it was this hard endpoint that stents trumped surgery. The stroke rate for CABG patients in the randomized trial was 2.2% versus 0.6% for stents and in the registry trial the stroke rate was 2.2%, Dr. Mohr said.
Keith D. Dawkins, M.D., associate chief medical officer at Boston Scientific, the maker of Taxus stents and sponsor of the trial, said the difference in the stroke rate might tip the balance in favor of stenting. In an interview, he predicted that patients would opt for a repeat procedure over the risk of stroke.
Not surprisingly, Dr. Dawkins also emphasized what he said was a shrinking gap between stents and surgery, noting that just a few years ago the difference in outcomes was 15% favoring surgery.
But others viewed the results in a less favorable light.
"Percutaneous coronary intervention failed to meet the primary endpoint," said Ray Gibbons, M.D., of the Mayo Clinic in Rochester, Minn. "If the endpoint is not met -- the message is very clear. These patients should go to surgery." Dr. Gibbons, a former president of the AHA, is an electrophysiologist.
Timothy Gardner, M.D., of the Center for Heart and Vascular Health in Wilmington, Del., the American Heart Association president, agreed.
For most patients with left-main disease or three-vessel disease, CABG should remain the standard, Dr. Gardner said.
He added that this was especially true because the data represent only 12 months experience. "Durability is a real advantage for CABG since we know that grafts are durable for more than 10 years," he said in an interview.
Dr. Gardner, a surgeon, said he would like to see at least five years of percutaneous coronoary intervention data before making any claims about durability.
Spencer B. King, III, M.D., of Saint Joseph's Heart and Vascular Institute in Atlanta, said he doubted that the findings will have any effect on treatment practices in the U.S.
"Eighty percent of these patients are referred to surgeons, and I think it will stay that way," Dr. King said.
The main reasons, according to Dr. King, were time and money.
In SYNTAX, the stent patients received an average of 4.6 stents to treat an average of 3.6 lesions and the average length was 86.1 mm. Treating lesions that long is time consuming, Dr. King said. "Few physicians want to spend that much time and hospitals may be reluctant to spend that much on stents."
The patients with left-main or three-vessel disease that do require stenting "will be sent to the few institutions that are willing to do that," Dr. King concluded.
Petr Widimský, M.D., D.Sc., of University Hospital Královské Vinohrady in Prague, who chaired the ESC press conference where the results were discussed, said the SYNTAX results had something for everyone.
"Surgeons are happy because they are still better, and the interventionalists are happy because they are not so bad," he said in an interview.
SYNTAX was funded by Boston Scientific, maker of the Taxus stent. Drs. Serruys and Mohr declared no conflicts. Dr. King disclosed income from Network for Continuing Medical Education, Best Industries, NorthPoint Domain, BG Medicine, Medtronic, and Cordis. Drs. Gardner and Widimský declared no conflicts. Dr. Gibbons said he had relationships with KAI Pharmaceuticals, TargeGen, Hawaii Biotech, Radianat Medical, and King Pharmaceutical.
Primary source: European Society of Cardiology
Source reference:
Serruys PW, Mohr FW "The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery: the SYNTAX Study" Hot Line II Sept. 1, 2008