CARONARY STENTS ~MARINA SOUZAN

Stents Stents are tiny, expandable tubes made of metal

mesh designed to open a blood vessel that is blocked by plaque. Over time, the artery wall heals around the stent.

STENT CLASSIFICATION

STENTS

Bare-Metal Stents

Drug-Eluting Stents

Bioabsorable DES-Stents

Bioengineered

StentCovered Stents (PTFE)

Stent structure Slotted tube stents

Modular stents

Multicellular stents

Modular-multicellular stent (hybrid stents)

TYPES OF STENTS 

Metal composition Open v/s closed cell designs Thickness of struts Eluting drugs Stent design may be specific -small

(<2.5 mm diameter) vessels / bifurcation lesions

Metal composition

Stainless steel designs - greater radial strength for aorto-ostial locations

Co-Cr - stronger & more radiopaque thinner struts, lower profiles (<0.40”), better flexibility & similar radial strength

Modular stents

Consist of several crown-shaped modules, which may be manufactured from metal wires that are punctually connected to form a tube ie, based on repeating identically designed

units, again laser-cut, linked together by welded struts

An ‘open-cell’ design Highly flexible Offer better side-branch access

Provides local delivery of a drug Methods for the storage and controlled

release Nondegradable polymers-

polyurethane, silicone, polyorganophosphazene, polymethacrylate, poly(ethylene terephthalate), & phosphorylcholine

Biodegradable polymer- poly(l-lactide), poly(3-hydroxybutyrate), polycaprolactone, polyorthoester, fibrin

Stent Coating

Stent coating

The eluted drug is linked by a degradable/permanent polymer coating only a few micrometers in thickness not expected to change mechanical

strength may affect surface friction Cavities on the stent struts- drug depots Small amounts of drugs applied

directly to stent surface

Intended to support a vessel for time to complete the healing process and to then disappear after a specified time period

Complications resulting from long-term intravascular presence of a FB- thrombogenicity, permanent mechanical irritation, prevention of positive remodeling, are eliminated

Poly(L-lactic acid) (PLLA), poly(D-lactic acid) (PDLA), poly(e-caprolactone) (PCL), poly(glycolic acid) (PGA)

Biodegradeable stents

Stent Design

The geometry of the stent must allow a sufficient area for delivery of the agent

Struts design.

Sites of action in the cell phase

Absorb Stent (Abbot lab) : Bioresorbable Vascular Scaffold (BVS) system that elutes everolimus

Bioresorbable Vascular Scaffold (BVS) system that elutes everolimus in a similar way to XIENCE V and then resorbs naturally into the body leaving no permanent scaffold.

Vascular Reparative Therapy (VRT). VRT is designed to restore the vessel to a more natural state, making natural vascular function possible. working in three phases to deliver VRT:RevascularisationRestorationResorptionhttp://www.ptca.org/news/2012/0928_ABBOTT_ABSORB.html

Challenging Stenting Techniques

Intimal Injury in Stenting:

Peripheral Stenting: Carotid Artery

http://www.medicalexpo.com/prod/abbott-vascular/carotid-stents-90137-572905.html#video

THANK YOU………….

https://www.youtube.com/watch?v=skchOEzWbn0