NEW YORK (Reuters Health) – Percutaneous placement of a sirolimus-eluting stent (SES) is a safe and effective way to address either bare-metal (BMS) or drug-eluting (DES) in-stent restenosis, according to a report this month in JACC: Cardiovascular Interventions from an international team of interventional cardiologists.
In the experience of Dr. Alexandre Abizaid from the Department of Interventional Cardiology, Instituto Dante Pazzanese de Cardiologia, Sao Paulo, Brazil and colleagues, SES deployment in this “challenging clinical scenario” has a high rate of acute success and relatively low incidence of serious adverse events at one year.
DES implantation has become the first choice for treatment of BMS in-stent restenosis, the clinicians say, but how best to treat DES in-stent restenosis remains less clear. “Intuitively,” many centers have opted to deploy another DES to treat restenosis, despite not having adequate data from a large randomized controlled trial to attest to its safety and efficacy.
Dr. Abizaid and colleagues analyzed data from the e-SELECT registry with 320 participating medical centers in 56 countries where the Cypher Select and Cypher Select Plus SES are approved for commercial use.
These two stents have the same polymer and amount of antiproliferative drug (with identical kinetic release profile); the only difference is slight modifications were made to the latest one to enhance flexibility and deliverability.
Among 15,147 patients in the e-SELECT registry, 1,590 (10.5%) had at least one in-stent restenosis who had at least one SES deployed between May 2006 and April 2008 to treat BMS restenosis (1,235 patients) or DES restenosis (355 patients). In-stent restenosis was defined as angiographic evidence of at least 50% stenosis within or 5 mm proximal and distal to the stent.
The researchers say procedural success and one-year clinical outcomes were equal for patients with successful deployment of either the Cypher Select or Cypher Select Plus SES. It should be noted that adherence to dual antiplatelet therapy was high in both groups (roughly 95% at 6 months and more than 81% at one year).
One-year clinical follow-up data, available on 1,089 of the patients in the DES group (88%) and 324 of those in the BMS group (91%), showed similar rates of death (2.1% and 1.4%, respectively) and MI (3.3% and 2.4%).
However, target lesion revascularization due to ischemia was higher in the DES group (7%) vs 3% in the BMS group. There was also a trend toward a higher rate of definite or probable late stent thrombosis in the DES group (2% vs 0.5%).
The finding of a higher late stent thrombosis rate in the DES group might be explained by the more complex clinical and angiographic characteristics of this cohort that included a significantly higher number of patients with diabetes, longer lesions, higher Charlson comorbidity index and renal insufficiency. All of these characteristics have been previously correlated with incremental occurrence of stent thrombosis, they say.
The investigators acknowledge that deployment of another DES, in particular a SES is not totally satisfactory in terms of target lesion revascularization recurrence. Yet, it has been the “most widely tested and most effective strategy” to deal with DES in-stent restenosis.
They also say it’s important to consider the mechanisms behind the failure of SES to treat a DES in-stent restenosis; in the current analysis, the only independent predictor of target lesion revascularization in these patients was residual stenosis greater than 20% at the end of the first procedure, “most probably often reflecting stent underexpansion.”
“Based on this finding, it is imperative to stress again the importance of adequate stent implantation technique, including aggressive stent post-dilation and, when needed, intravascular ultrasound guidance, as a way to optimize acute procedure results and minimize the risk of in-stent restenosis recurrence.”
The Cypher Select and Cypher Select Plus SES are manufactured by Cordis Corporation of Bridgewater, New Jersey. Several of the authors have disclosed financial ties to the company. A complete list can be found with the original article.
