Stents in small vessels - which to use?
The two most popular drug-eluting stents, one coated with the drug sirolimus (Cypher; Johnson & Johnson) and the other coated with the drug paclitaxel (Taxus; Boston Scientific) are amazing devices that have revolutionized the treatment of coronary artery disease.
Both, sirolimus- and paclitaxel-eluting stents effectively reduce restenosis in small coronary vessels. But, which one is more effective?
A new study indicates that the sirolimus-eluting stent performs better in small coronary vessels. Angiographic restenosis was found in 19.0% of the lesions in the paclitaxel-eluting stent group and 11.4% of the lesions in the sirolimus-eluting stent group. Target lesion revascularization was performed in 14.7% of the lesions treated with paclitaxel-eluting stents and 6.6% of the lesions treated with sirolimus-eluting stents.
Therefore, the paclitaxel-eluting stent is associated with a greater late luminal loss (loss of artery opening when compared to the lumen post-implantation) and is less effective in reducing restenosis in small coronary vessels than the sirolimus-eluting stent.
A 2005 study on individuals with diabetes came to the same conclusion.
A 2005 meta-analysis also came to the same conclusion.
Dr. David J. Moliterno, a cardiologist at the University of Kentucky in Lexington stated that, "the large majority of patients...will have extremely terrific outcomes with either stent."
However, the Cypher stent may be useful in more complex cases, such as insulin-dependent diabetics, those with kidney disease or patients who have already had a stent implanted and now require second procedure. [And, now, in patients who have stenoses in small arteries.]
He noted that it's unlikely that the components influencing the differences in outcomes will ever be identified, since new stents with various stent struts, polymers and drugs are under development.
"Because the rate of failure is so low, future studies will need to be either very large or among particularly high-risk patients to discern a possible difference between future generation stents," he said.