Incomplete Stent Apposition and Very Late Stent Thrombosis After Drug-Eluting Stent Implantation

Abstract

Background— Stent thrombosis may occur late after drug-eluting stent (DES) implantation, and its cause remains unknown. The present study investigated differences of the stented segment between patients with and without very late stent thrombosis with the use of intravascular ultrasound. Methods and Results— Since January 2004, patients presenting with very late stent thrombosis (>1 year) after DES implantation underwent intravascular ultrasound. Findings in patients with very late stent thrombosis were compared with intravascular ultrasound routinely obtained 8 months after DES implantation in 144 control patients, who did not experience stent thrombosis for ≥2 years. Very late stent thrombosis was encountered in 13 patients at a mean of 630±166 days after DES implantation. Compared with DES controls, patients with very late stent thrombosis had longer lesions (23.9±16.0 versus 13.3±7.9 mm; P <0.001) and stents (34.6±22.4 versus 18.6±9.5 mm; P <0.001), more stents per lesion (1.6±0.9 versus 1.1±0.4; P <0.001), and stent overlap (39% versus 8%; P <0.001). Vessel cross-sectional area was similar for the reference segment (cross-sectional area of the external elastic membrane: 18.9±6.9 versus 20.4±7.2 mm 2 ; P =0.46) but significantly larger for the in-stent segment (28.6±11.9 versus 20.1±6.7 mm 2 ; P =0.03) in very late stent thrombosis patients compared with DES controls. Incomplete stent apposition was more frequent (77% versus 12%; P <0.001) and maximal incomplete stent apposition area was larger (8.3±7.5 versus 4.0±3.8 mm 2 ; P =0.03) in patients with very late stent thrombosis compared with controls. Conclusions— Incomplete stent apposition is highly prevalent in patients with very late stent thrombosis after DES implantation, suggesting a role in the pathogenesis of this adverse event.

Long‐Term Clinical Outcomes After Angiographically Defined Very Late Stent Thrombosis of Drug‐Eluting Stent

“…From these results, we reconfirmed that VLST may be rare, but its consequences are dangerous. Procedural and pathologic risk factors such as local hypersensitivity reaction of the stent; ostial and/or bifurcation stenting; malapposition/incomplete apposition of struts 6 ; restenosis; and strut penetration into a necrotic core could affect occurrences of VLST and poor endothelialization has been proposed as the most important pathologic predictor of late stent thrombosis. The latter factors might affect long-term outcomes.…”

“…5,6 Statistical Analysis Data are expressed as mean ± standard deviation (SD) for continuous variables and as frequencies for categorical variables. Major adverse cardiac event-free survival distributions were estimated according to the Kaplan-Meier method.…”

Enterprise Stent-assisted Cerebral Aneurysm Coiling: Can Antiplatelet Therapy be Terminated after Neointima Formation with the Enterprise Stent?

“…Delayed ischemic events occurred in 8 (16%) of 50 cases, and all cases involved patients with incomplete stent apposition. In patients undergoing drug-eluting stent placement for coronary artery disease, several studies 14,15) suggested that delayed arterial healing and stent malapposition may be important causes of very late stent thrombosis (thrombosis at >1 year after stent deployment).…”

Application of Optical Coherence Tomography in Percutaneous Coronary Intervention

“…A previous IVUS study demonstrated that stent malapposition was highly prevalent in patients with very late stent thrombosis after DES implantation. 31 Subsequently, an angiographic registry showed that late acquired peri-stent contrast staining after DES implantation, which might represent an abnormal vessel wall response such as stent malapposition and positive vessel remodeling, was associated with subsequent target-lesion revascularization and very late stent thrombosis 32 (Figure 4). 15.1±4.6 mm 2 , P=0.003) were associated with late stent thrombosis.…”