Mystery solved? Research blames ruptured plaque for stent related blood clots
South Korean scientists believe they may have solved what causes very late stent thrombosis (blood clots) after drug-eluting or bare-metal stent implants. And their solution opens up a door to treating long-term stent patients and helping to boost their survival rates.
The condition has long been mysterious and can kill a patient if not properly addressed. But a team from the University of Ulsan College of Medicine in Seoul and colleagues believe very late stent thrombosis takes place after plaque buildup inside the stent ruptures. And they found that in a large number of patients with drug-eluting stents who experienced late stent thrombosis or blood clots, the problem could be tied to plaque rupturing inside the stents. Details are published in the Journal of the American College of Cardiology: Cardiovascular Imaging, and MedPage Today highlights the findings.
As the story explains, the cause of late stent thrombosis has been a matter of debate. But if the plaque buildup is to blame, it points to both a problem and opportunity in studying long-term stent impacts. Importantly, device companies may now have a potential target to address in improving stent safety and performance down the line. If they can minimize stent plaque buildup, they can help potentially prevent the condition in the first place.
According to the article, 22 of Johnson & Johnson's ($JNJ) Cypher products, three of Boston Scientific's ($BSX) Taxus models and one of Abbott's ($ABT) Xience stents were among those scrutinized for the study. Overall, 27 patients received drug-eluting stents and 6 got the bare-metal variety. All of the bare-metal stents generated ruptured plaque, and two-thirds of the drug-eluting stents had the same result.
Results for 17 out of the 27 patients who received drug-eluting stents and faced very late stent thrombosis point to plaque rupturing inside the stent as the cause--worse than rates seen in previous research, the article explains. The researchers also found that in a good number of patients with drug-eluting stents that had lesions that ruptured, the stents were poorly placed, a problem that didn't happen with bare-metal stents.
Average follow-up ranged from 5 years for drug-eluting-stent-treated lesions to 9 years for patients with bare-metal stents.