Safety Profile of Drug-eluting Stents Similar to Bare-metal Stents
Lower restenosis rates associated with DES.
An article published Tuesday in the Wall Street Journal inaccurately characterized two major drug-eluting stents as unsafe, despite a comprehensive review of data that suggests otherwise.
In a talk given Monday, Gregg W. Stone, MD, Chairman of the Cardiovascular Research Foundation and Professor of Medicine at Columbia University Medical Center in New York, said that although the risk of blood clots increased 0.6% and 0.4% four years after implantation of the Cypher and Taxus stents, respectively, use of these stents reduces the risk of acute ischemic events associated with restenosis. Drug-eluting stents, Stone said, decrease the need for additional intervention and mortality associated with restenosis.
The Wall Street Journal article, “Drug-coated Stents Show Use Risk,” examined only four-year clotting data and overlooked these significant points.
Review of 17 trials
Stone cited a review of 17 randomized controlled trials that examined noncardiac mortality rates in patients treated with bare-metal stents and patients treated with drug-eluting stents (Figure on pg 5). According to this review, noncardiac mortality rates are lower among patients treated with drug-eluting stents.
Prospective, randomized trials
Stone also cited nine prospective, double-blind randomized trials that compared patients treated with bare-metal stents with those treated with Cypher (Cordis/Johnson & Johnson) or Taxus (Boston Scientific) stents.
The four trials comparing use of the Cypher stent with a bare-metal stent (RAVEL, SIRIUS, E-SIRIUS, C-SIRIUS) indicated that after four years, 92.2% of patients treated with a Cypher stent remained free from ischemic target lesion revascularization (TLR). In comparison, 76.4% of patients treated with a bare-metal stent remained free from ischemic TLR after four years (P = .0001).
The five trials comparing the Taxus stent with a bare-metal stent (TAXUS I, II, III, IV, V) indicated that after four years, 89.9% of patients treated with a Taxus stent remained free from ischemic TLR. After four years, only 80% of patients treated with a bare-metal stent remained free from ischemic TLR (P = .0001).
Stent thrombosis rates
After four years, 99.4% of patients treated with a bare-metal stent remained free of stent thrombosis vs. a statistically equivalent 98.8% of patients treated with a Cypher stent (P = .2). This rate was also statistically equivalent between bare-metal stents and the Taxus stent (99.1% with bare-metal stents vs. 98.7% with Taxus, P = .29).
Rates of other important endpoints at four years, including freedom from all-cause death and freedom from cardiac death, were equivalent in patients treated with Taxus or Cypher stents vs. patients receiving bare-metal stents.
Stone said these data indicate that when all aspects of long-term outcome are considered, the safety profiles for bare-metal stents and drug-eluting stents are similar.
More national press
A New York Times blog entry (www.nytimes.com) by reporter Barnaby Feder also addressed the drug-eluting stent issues discussed at this year’s TCT.
In his article, “Doctors Debate Safety of Stents for Heart Patients,” Feder noted that a large number of presentations at TCT 2006 appropriately addressed the dilemma many interventional cardiologists face when it comes to drug-eluting vs. bare-metal stent technology.
Feder noted that the stent safety debate continues in many forms and that physicians and researchers are ultimately left to address issues critical to patient safety. Which patients are most vulnerable? Are the alternatives to interventional procedures really any better? And how much risk of clotting do drug-eluting stents actually pose?
As Stone noted during his presentation Monday, an adequately powered study would need about 50,000 patients to definitively address all of these issues.