269 - Pathology of coronary artery after third-generation drug-eluting stent implantation in low-density lipoprotein receptor knockout mini pigs and human autopsy cases. (ID 648)
Abstract
Background and Aims
Third-generation drug-eluting stent (3rd DES) is widely used in percutaneous coronary intervention. Clinical superiority of 3rd DES has been demonstrated, however, pathological response after 3rd DES remains unclear. We aimed to examine the histology after 3rd DESs in low-density lipoprotein receptor knockout (LDLR -/-) mini pigs and human autopsy cases.
Methods
Using LDLR -/- mini pigs, second-generation drug-eluting stents (2nd DES; Promus-PREMIER, Boston Scientific, Marlborough, MA) and 3rd DESs (SYNERGY, Boston Scientific, Marlborough, MA) were deployed in coronary arteries. One month later, in-vivo optical coherence tomography (OCT) assessment was performed. The stent-implanted arteries were dissected and investigated histologically. Likewise, using specimens obtained by human autopsy, we compared the histology between 3rd and 2nd DESs lesions.
Results
OCT analysis of porcine coronaries showed that the neointimal area of 3rd DESs were homogenous and smaller (3rd DESs; 1.90 ± 0.03 mm2, 2nd DESs; 2.05 ± 0.07 mm2, P < 0.05). In human coronaries, the ratio of covered struts and thickness of neointima of 3rd DESs were 0.82 ± 0.03 and 58.9 ± 7.4μm, while those of 2nd DESs were 0.75 ± 0.02 and 33.6 ± 2.7μm, respectively. Fibrin deposition around struts was smaller in 3rd DESs in porcine model and human specimens.
Conclusions
Our pathological analysis showed advanced healing process in 3rd DES compared to 2nd DES lesions, in the viewpoint of strut coverage by matured neointima both in human and atherosclerotic porcine model. These results might be considered as an important evidence in the early termination of antiplatelet drugs after 3rd DESs.
