EXPERIMENTAL RESEARCH CORONARY INTERVENTIONS EuroIntervention 2015;11:433-441 published online ahead of print April 2014 DOI: 10.4244/EIJV11I4A85 433 © Europa Digital & Publishing 2015. All rights reserved. *Corresponding author: Department of Cardiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Wien, Austria. E-mail: mariann.gyongyosi@meduniwien.ac.at Preclinical randomised safety, efficacy and physiologic study of the silicon dioxide inert-coated Axetis and bare metal stent: short-, mid- and long-term outcome Noemi Pavo 1 , MD, MSc; Bonni Syeda 1 , MD; Andreas Bernhart 1 , MD; Eszter Szentirmai 2 , PhD; Rayyan Hemetsberger 1 , MD; Eslam Samaha 1 , MD; Christian Plass 1 , MD; Katrin Zlabinger 1 , BSc; Imre J. Pavo 1 , MD; Zsolt Petrasi 2 , PhD; Örs Petnehazy 2 , PhD; Simon P. Hoerstrup 3 , MD, VMD; Gerald Maurer 1 , MD; Mariann Gyöngyösi 1 *, MD, PhD 1. Department of Cardiology, Medical University of Vienna, Vienna, Austria; 2. Institute of Diagnostic Imaging and Radiation Oncology, University of Kaposvar, Kaposvar, Hungary; 3. Cardiovascular Research and Regenerative Medicine Program, University and University Hospital, Zürich, Switzerland N. Pavo and B. Syeda contributed equally to the work. The references can be found in the online version of this paper at the following website: http://www.pcronline.com/eurointervention/87th_issue/85 Abstract Aims: To evaluate the short-, mid- and long-term safety, efficacy and vascular physiology of Axetis silicon dioxide (SiO 2 , abrading the micropores) inert-coated stent implantation in a randomised preclinical setting. Methods and results: Coronary arteries of domestic pigs were randomised to receive either Axetis or BMS (same design) stents with one-, three- and six-month follow-up (FUP), controlled by coronary angi- ography, optical coherence tomography (OCT), intravascular ultrasound (IVUS) and histology (n=32). The time-dependent vasomotor reaction of coronary arteries to stenting was measured using modified myogra- phy (n=12). Complete endothelialisation of the Axetis stent was confirmed by OCT, IVUS and histology at one-month FUP. Histopathology revealed continuous healing of the vessel wall with a gradual reduction of inflammation and fibrin score during the six-month FUP in both stent types. Significantly smaller neointimal area and %area stenosis were measured in Axetis stents compared with BMS at each FUP time point. Vascular reactivity measurements showed significantly better endothelium-dependent vasodilation of stented arteries with Axetis implantation. Conclusions: Implantation of the Axetis SiO 2 -coated stent resulted in a significantly better safety, efficacy and vessel physiology profile compared with BMS of the same design with a continuous decrease in vessel inflammation during the six-month FUP. KEYWORDS • histology • inert-coated stent • late lumen loss • preclinical study • stent thrombosis • vascular response SUBMITTED ON 03/10/2012 - REVISION RECEIVED ON 06/03/2013 - ACCEPTED ON 14/05/2013