Is stent length important when considering drug-eluting stent surgery?

This study looked at whether stent length affects clinical outcomes after drug-releasing (eluting) stent implantation. 

Stenting (balloon angioplasty or percutaneous coronary intervention) is a surgery carried out on patients with coronary artery disease. Coronary artery disease refers to a condition caused by the narrowing of blood vessels that supply the heart with blood, oxygen and nutrients, often due to cholesterol buildup. 

Stenting surgery involves the insertion of a small flexible tube into the blood vessel, normally in the groin area. The tube is moved along the blood system until it reaches the narrowed artery and a small balloon within the tube is then inflated within the artery to dilate it and improve blood flow. Sometimes the stent is a drug-eluting stent that slowly releases a drug over time to help prevent the blockage from recurring.

Drug-eluting stents have greatly reduced the need for repeat stenting surgeries. However, blood clotting (which can lead to a heart attack or stroke) and the need for additional stenting surgery is often required in patients who receive long first generation stents (first group of drug-eluting stents on the market). First generation stents include Cypher and TAXUS, which release drugs such as sirolimus (Rapamune) and paclitaxel (Taxol) respectively. Newer generation drug-eluting stents include Endeavor Resolute and Xience V that release drugs such as zotarolimus and everolimus. All stents work to prevent narrowing of arteries but they differ in material, drug and time course of drug release. 

This study investigated whether longer stent length is associated with more adverse effects in patients that received first and newer generation drug-eluting stents. 

This study was conducted on 8,445 patients who underwent stenting surgery, of which 6,334 patients received first-generation drug-eluting stents and 2,111 patients received newer-generation drug-eluting stents. Stent length was divided into either being <32 mm or >32mm.

Clinical outcomes (health status) of the patients were measured 3 years after the surgery. These included the occurrence of mortality (death), heart attack, blood clot within the stent, and the need for repeated stenting surgery. A stent length of >32mm was significantly associated with higher incidence of blood clots in patients treated with first-generation drug-eluting stents, however no association was found between stent length and clinical outcome in patients treated with newer-generation drug-eluting stents.

The study concluded that while stent length may affect clinical outcome in patients that receive first-generation drug-eluting stents, it does not affect those that receive newer-generation stents. 

Long stents may have been used in patients with more advanced coronary artery disease, hence there is a possibility that the adverse effects of longer stent length may be a result of severe coronary artery disease and not stent length alone.  

If you or someone you know are considering have stent surgery, talk to a doctor about the length of stent that will be used as the clinical outcomes may be better with a stent <32mm long.