my personal edition > cardiology other > news


  E-Mail this DGDispatch to a colleague

DGDispatch

Sirolimus-Eluting Stents Remain Superior to Bare Metal Stents at 2 Years: Presented at ESC

By Chris Berrie

STOCKHOLM, SWEDEN -- September 12, 2005 -- The use of sirolimus-eluting stents provides evidence of the superiority of drug-eluting stents (DES) over bare metal stents (BMS) both under specific graft procedures and on the basis of unselected "all-comer" patients with complex disease, according to two studies presented here at the European Society of Cardiology (ESC) Congress 2005.

In introducing the first study on September 5^th, principal investigator Paul Vermeersch, MD, Head of Interventional Cardiology, AZ Middelheim Cardiology, Antwerp, Belgium, said, "Drug-eluting stents have been shown to be highly successful in reducing restenosis in native coronary disease; however, the atherosclerotic process and the mechanism of in-stent restenosis in saphenous vein grafts differ from the situation in native coronary arteries."

To determine the safety and efficacy of DES versus BMS for treatment of de novo lesions in saphenous vein grafts (SVGs), Dr. Vermeersch and colleagues conducted a prospective, randomised single-centre study.

The study population had a target vessel diameter from 2.5 to 4.5 mm (by visual estimate), target lesion stenosis was 50% or greater (by visual estimate), and were diagnosed with angina pectoris, unstable angina pectoris or documented silent ischaemia.

Stenting-related exclusion criteria included lesions that required more than two stents (>66 mm), a prior stent within 5 mm of the target vessel, and totally occluded vessels. The remaining exclusion criteria were as standard for other such studies.

Between September 2003 and November 2004, 75 patients were randomised to Cypher sirolimus-eluting stents (n = 38; mean age, 73 years; male, 80%) or BX sonic BMS (n = 37; mean age, 72 years; male, 85%). The baseline characteristics across these two groups showed no significant differences.

The procedure was generally direct stenting with the use of a distal protection device, using the "healthy to healthy" tissue technique. Across these 75 patients, 78 grafts and 96 lesions were treated (DES, 47; BMS, 49), with mean stented lengths of 29 mm and 26 mm, respectively. All of the procedures across both of the stent types were both angiographic and clinical successes.

At 1 month, there were no major adverse cardiac events (MACE), although DES showed significant reductions in in-stent (52%; P = .001) and in-segment (41%; P = .01) late loss, as compared to BMS. This resulted in a corresponding decrease in the binary restenosis rate in favour of DES (in-stent, 63%; in-segment, 58%).

At 6 months, the total MACE was in favour of DES, with the difference from BMS driven by the significantly higher target vessel restenosis (TVR) with BMS (P = .02).

Dr. Vermeersch concluded that the use of cipher stents for SVG lesions resulted in a significant reduction in the late loss and binary stenosis both in-stent and in-segment, with no safety issues arising in the first 6 months.

Another study, presented at the ESC on September 6^th, looked at the long-term outcome of the unrestricted use of sirolimus-eluting stents in an all-comers population.

This 2-year study analysed data from the RESEARCH (Rapamycin-Eluting Stent Evaluation at Rotterdam Cardiology Hospital) registry, where a policy was adopted in April 2002 for sirolimus DES as default strategy for percutaneous coronary intervention. Co-principal investigator Andrew T.L. Ong, MD, Senior Research Fellow, Department of Interventional Cardiology, Thorax Centre, Erasmus Medical Centre, Rotterdam, The Netherlands, said, "Our study is unique in the sense that we were the first to use drug-eluting stents in all patients."

This study includes the first 508 DES patients (mean age, 61 years; male, 68%) after this policy change, with the last consecutive 450 BMS patients (mean age, 61 years; male, 72%). The main baseline and angiographic characteristics of these two groups were well balanced, although there were significantly fewer patients with previous MI in the DES group (30%, vs. 40% for BMS; P < .01).

For the procedural characteristics of the stenting, however, there were a number of significant differences (DES vs. BMS): bifurcation stenting (16% vs. 8%; P < .01), number of stented segments (2.0 vs. 1.8; P < .01), number of implanted stents (2.1 vs. 1.9; P < .01), total stented length per patient (38.7 vs. 30.1 mm: P < .01), use of stent >/= 33 mm (35% vs. 10%; P < .01) and nominal stent diameter </= 2.5 mm (36% vs. 23%; P < .01). The angiographic success of all lesions in each group was given as 97%.

At 2 years, there were no significant differences in mortality between DES and BMS (5.8% vs. 6.3%, respectively), or in the combined endpoint of death or MI (9.7% vs. 10.9%). However, there was significantly less TVR with DES (8.2%, vs. 14.8% for BMS; P = .002), which drove the significance of the 2-year incidence of the combined endpoint of MACE (15.4%, vs. 22.0% for BMS; P = .01).

Dr. Ong noted that over this second year, there was non-significance between the stenting groups for all of the 53 events that occurred, thus indicating the continuing, and still improving, benefit of DES over BMS in this long-term follow-up.

After multivariate analysis and adjustment for independent predictors, the use of DES also conferred a significant protective effect against both TVR (P < .001) and MACE (P = .001) in this 2-year follow-up.

This study from the RESEARCH register thus demonstrates that in the "real world", DES reduces the incidence of MACE at 2 years, primarily by reducing the need for TVR, as compared to BMS, with no evidence for a late catch-up effect being seen, the researchers concluded.

Dr. Ong said this second study also has the benefit of no limitations being imposed on the choice of stent use. This is today an important consideration in most countries, and with these continuing analyses now providing documented evidence of the advantage of DES over BMS, both under specific graft procedures and on an all-comer basis, the hope is that these restrictions can be relaxed so as to provide the best patient benefit, he said.


[Presentation titles: Randomised Trial Comparing Sirolimus-Eluting Stents Versus Bare-Meal Stents in Severely Diseased Saphenous Vein Graft Treatment: Six Month Clinical and Angiographic Outcome. Abstract 2000; Sirolimus-Eluting Stents Remain Superior to Bare Metal Stents at 2 Years in the Real World: Long-Term Results from the RESEARCH Registry. Abstract P2901 (In Press, JACC)]

E-Mail this DGDispatch to a colleague

To print, use this version