title: A new polymer-free drug-eluting stent with nanocarriers eluting sirolimus from stent-plus-balloon compared with bare-metal stent and with biolimus A9 eluting stent in porcine coronary arteries.
abstract: BACKGROUND
  Permanent polymers in first generation drug-eluting stent (DES) have been imputed to be a possible cause of persistent inflammation, remodeling, malapposition and late stent thrombosis. We aim to describe the in vivo experimental result of a new polymer-free DES eluting sirolimus from stent-plus-balloon (Focus np stent, Envision Scientific) compared with a bare-metal stent (BMS) (Amazonia CroCo, Minvasys) and with a biolimus A9 eluting stent (Biomatrix, Biosensors).
  
  
  METHODS
  In 10 juvenile pigs, 23 coronary stents were implanted in the coronary arteries (8 Amazonia CroCo, 8 Focus np, and 7 Biomatrix). At 28-day follow-up, optical coherence tomography (OCT) and histology were used to evaluate neointimal hyperplasia and healing response.
  
  
  RESULTS
  According to OCT analysis, Focus np stents had a greater lumen area and less neointimal hyperplasia response than BMS and Biomatrix had. Histomorphometry results showed less neointimal hyperplasia in Focus np than in BMS. Histology showed a higher fibrin deposition in Biomatrix stent compared to Focus np and BMS.
  
  
  CONCLUSIONS
  The new polymer-free DES with sirolimus eluted from stent-plus-balloon demonstrated safety and reduced neointimal proliferation compared with the BMS and Biomatrix stents at 28-day follow-up in this porcine coronary model. This new polymer-free DES is promising and warrants further clinical studies.
authors.affiliation: 1 Department of Interventional Cardiology, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil ; 2 Envision Scientific Pvt. Ltd., Office 1-3, Silver Palm II, Opposite Snehmilan Garden, Kadampalli, Nanpura, Surat, Gujarat, India.
authors.forename: Celso K
authors.initials: CK
authors.lastname: Takimura
authors.affiliation: 1 Department of Interventional Cardiology, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil ; 2 Envision Scientific Pvt. Ltd., Office 1-3, Silver Palm II, Opposite Snehmilan Garden, Kadampalli, Nanpura, Surat, Gujarat, India.
authors.forename: Micheli Z
authors.initials: MZ
authors.lastname: Galon
authors.affiliation: 1 Department of Interventional Cardiology, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil ; 2 Envision Scientific Pvt. Ltd., Office 1-3, Silver Palm II, Opposite Snehmilan Garden, Kadampalli, Nanpura, Surat, Gujarat, India.
authors.forename: Paulo S
authors.initials: PS
authors.lastname: Gutierrez
authors.affiliation: 1 Department of Interventional Cardiology, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil ; 2 Envision Scientific Pvt. Ltd., Office 1-3, Silver Palm II, Opposite Snehmilan Garden, Kadampalli, Nanpura, Surat, Gujarat, India.
authors.forename: Prakash
authors.initials: P
authors.lastname: Sojitra
authors.affiliation: 1 Department of Interventional Cardiology, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil ; 2 Envision Scientific Pvt. Ltd., Office 1-3, Silver Palm II, Opposite Snehmilan Garden, Kadampalli, Nanpura, Surat, Gujarat, India.
authors.forename: Ashwin
authors.initials: A
authors.lastname: Vyas
authors.affiliation: 1 Department of Interventional Cardiology, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil ; 2 Envision Scientific Pvt. Ltd., Office 1-3, Silver Palm II, Opposite Snehmilan Garden, Kadampalli, Nanpura, Surat, Gujarat, India.
authors.forename: Manish
authors.initials: M
authors.lastname: Doshi
authors.affiliation: 1 Department of Interventional Cardiology, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil ; 2 Envision Scientific Pvt. Ltd., Office 1-3, Silver Palm II, Opposite Snehmilan Garden, Kadampalli, Nanpura, Surat, Gujarat, India.
authors.forename: Pedro A
authors.initials: PA
authors.lastname: Lemos
keywords: Neointimal; restenosis; stent; vascular injury