Stenting: Function, Problems, and Stenting: Function, Problems, and ProcedureProcedure

Uses for StentsUses for Stents

Peripheral artery disease (PAD)Peripheral artery disease (PAD) Renal vascular hypertensionRenal vascular hypertension Hemodialysis access maintenance Hemodialysis access maintenance Coronary artery disease (CAD)Coronary artery disease (CAD) Carotid artery diseaseCarotid artery disease AneurysmsAneurysms

HistoryHistory

Percutaneous Interventional cardiology Percutaneous Interventional cardiology introduced in 1977.introduced in 1977.

Stenting first performed in the mid 1980’s. Stenting first performed in the mid 1980’s. FDA approved it in 1994.FDA approved it in 1994.

70-90% of balloon angioplasty procedures 70-90% of balloon angioplasty procedures now use a stent.now use a stent.

Currently 1,500,000 stenting procedures Currently 1,500,000 stenting procedures performed annually. performed annually.

Stent TypesStent Types

Components- stainless steel with different Components- stainless steel with different designs. designs.

DesignsDesigns Drug-eluting Drug-eluting

stentsstents SizesSizes

Drug-eluting StentsDrug-eluting Stents

SirolimusSirolimus– Immunosuppressive Immunosuppressive

agent used for solid agent used for solid organ transplant.organ transplant.

– Coated with Coated with 140mcg/cm^2.140mcg/cm^2.

– Releases over 14-28 Releases over 14-28 days.days.

PaclitaxelPaclitaxel– Chemotherapeutic drug Chemotherapeutic drug

used to treat patients used to treat patients with ovarian or breast with ovarian or breast cancer.cancer.

– Coated with Coated with 3mcg/cm^2.3mcg/cm^2.

– Released over at least Released over at least a ten day period.a ten day period.

ProcedureProcedure

Sterile Table.Sterile Table. Clean entry site- femoral Clean entry site- femoral

or brachial artery.or brachial artery. Cut into skin.Cut into skin. Catheterization, with use Catheterization, with use

of a guide wire.of a guide wire. Inject contrast to visualize Inject contrast to visualize

vessels.vessels. Balloon angioplasty.Balloon angioplasty. Stent attached to deflated Stent attached to deflated

balloon and takent to site.balloon and takent to site.

RestenosisRestenosis

Reclosure of the arteryReclosure of the artery Bare metal stents rate is around 20-30%Bare metal stents rate is around 20-30% Drug-eluting stents rate is around 9%Drug-eluting stents rate is around 9% Usually recurrence timeUsually recurrence time Most vulnerable- those with diabetes, long Most vulnerable- those with diabetes, long

stents (35mm+), or in small arteriesstents (35mm+), or in small arteries Why it occursWhy it occurs

Post ProcedurePost Procedure

Pressure and dress Femoral arteryPressure and dress Femoral artery Take proscribed medicationsTake proscribed medications Limit activities- lift no more than 10 poundsLimit activities- lift no more than 10 pounds Other restrictions depending on extent of Other restrictions depending on extent of

heart disease.heart disease. Get exercise- 3-4 days a week for around Get exercise- 3-4 days a week for around

30 mins. Walking is best.30 mins. Walking is best. No MRI’s for at least six months. No MRI’s for at least six months.

Contraindicators and ComplicationsContraindicators and Complications

ContraindicatorsContraindicators– Size of the arterySize of the artery– Where the blockage is Where the blockage is

locatedlocated– Other BlockagesOther Blockages– Condition of the heartCondition of the heart– AllergiesAllergies

ComplicationsComplications– Blood clots Blood clots – Tearing the arteryTearing the artery– Abrupt vessel closureAbrupt vessel closure– Excessive bleeding Excessive bleeding

through femoral arterythrough femoral artery– Heart attack or sudden Heart attack or sudden

cardiac deathcardiac death– StrokeStroke

Plaque ClassificationsPlaque Classifications

HomogeneousHomogeneous– Usually whiteUsually white– Smooth outer surfaceSmooth outer surface– Consistent texture Consistent texture

throughoutthroughout

HeterogeneousHeterogeneous– Yellowish colorYellowish color– Rough edgesRough edges– Inconsistent textureInconsistent texture– More likely to rupture More likely to rupture

and have blood clotsand have blood clots StentingStenting

– After six months will After six months will grow thin layer of cellsgrow thin layer of cells

– Now classified as Now classified as homogeneoushomogeneous