Author + information
- Sho Torii1,
- Frank Kolodgie1,
- Eduardo Acampado2,
- Kazuyuki Yahagi1,
- Hiroyoshi Mori3,
- Maria Romero4,
- Laura Perkins5,
- Syed Hossainy5,
- Stephen Pacetti5,
- Aloke Finn6,
- Renu Virmani1 and
- Qi Cheng1
- 1CVPath Institute, Inc., Gaithersburg, Maryland, United States
- 2University Hospital La Timone
- 3CVPath institute, North Bethesda, Maryland, United States
- 4Duke Clinical Research Institute
- 5Abbott Vascular, Santa Clara, California, United States
- 6CVPath Institute Inc. and University of Maryland, Baltimore, Gaithersburg, Maryland, United States
A recent comprehensive network meta-analysis established that cobalt-chromium everolimus eluting (CoCr-EES) stents had significantly lower rate of stent thrombosis than bare metal or bioerodible polymer drug-eluting stents. To further explore the mechanism of this safety finding, Xience fluoropolymer-only stents without everolimus (XFP) were tested in an acute low-heparin extracorporeal shunt model.
The thrombogenicity of XFP relative to Multi-link Vision bare metal stents (BMS) (n=5/stent) were assessed acutely using an established ex vivo carotid to jugular arteriovenous porcine shunt model (Otsuka F et al., JACC Cardiovasc Interv 8:1248-1260, 2015). The stents were bisected and each half was dual immunostained using platelet cocktail (CD61/CD42b) and inflammatory marker for neutrophils (PM1) or monocytes (CD14). Antibody staining was visualized by confocal microscopy and quantified by histomorphometry.
XFP showed significantly lower platelet adherence and aggregation compared with BMS (area percentage 5.9 vs. 21.0, P= 0.04). Moreover, XFP showed numerically less inflammatory cell adherence as compared to BMS for both neutrophils (286.4±101.4 vs. 366.0±137.9 positive cells/mm2) and monocytes (186.0±35.0 vs. 229.3±93.2 positive cells / mm2), although differences did not achieve statistical significance.
Fluoropolymer coating imparts greater thromboresistance as compared to Vision, which reflects a unique phenomenon known as fluoropassivation and represents one proposed mechanism for the clinically observed low coronary thrombosis rates attributed to Xience.
CORONARY: Stents: Drug-Eluting