Stent thrombosis after PCI rare, but associated with worse outcomes

Despite advancements in stents and medication, stent thrombosis (ST) continues to occur in rare occasions following percutaneous coronary intervention (PCI), a recent study has shown. In turn, ST amplifies mortality in these patients.

The study included 41,137 patients (mean age, 66.0±11.9 years; 23.5 percent female) who underwent PCI. ST was defined according to the criteria of the Academic Research Consortium, and its impacts on 30-day outcomes—such as all-cause mortality, major bleeding, emergency PCI, and new stroke—was assessed.

Over the 5-year study period, only 225 definite and probable STs were detected, yielding a small incidence rate of 0.55 percent.

Patients who developed ST were less likely to have received drug-eluting stents (p=0.01) but were more likely to have undergone PCI to lesions in the left anterior descending or left main arteries (p=0.03 overall for lesion location). Dual antiplatelet therapy was also less common among ST patients (p<0.01), who were more frequently discharge without any antiplatelet medication (p<0.001).

In terms of outcomes, ST correlated with a 23.6-percent mortality rate at 30 days. In comparison, those without ST only saw a corresponding rate of 1.1 percent (p<0.001).

Major bleeding likewise occurred significantly more frequently in ST patients (8.4 percent vs 1.1 percent; p<0.001), as did emergent PCI or coronary artery bypass grafting procedures (20.0 percent vs 4.0 percent; p<0.001).

“The results of this registry-based study of a large cohort of unselected patients undergoing PCI suggest that, even with new generation stent technology and adjunctive medication, ST occurs following approximately 1 in every 200 PCIs. In the contemporary setting, ST is associated with increased risk of mortality at 30 days,” researchers said.