Coronary StentsCoronary StentsRDSC 326RDSC 326

Basic Anatomy of the Basic Anatomy of the Coronary SystemCoronary System

• Right coronary artery (RCA)Right coronary artery (RCA)• Originates above right cusp of the Originates above right cusp of the

aortic valve, travels down right aortic valve, travels down right atrioventricular groove, towards the atrioventricular groove, towards the crux of the heart crux of the heart

• Right marginal arteryRight marginal artery• Supplies blood to the right side of the heart Supplies blood to the right side of the heart

• Posterior descending artery (PDA)Posterior descending artery (PDA)• Supplies blood to the apex of the heart and Supplies blood to the apex of the heart and

the posterior ventricular walls the posterior ventricular walls

Basic Anatomy of the Basic Anatomy of the Coronary SystemCoronary System

• Left coronary artery (LCA)Left coronary artery (LCA)• Arises from aorta above left cusp of Arises from aorta above left cusp of

the aortic valve the aortic valve • Left anterior descending (LAD) arteryLeft anterior descending (LAD) artery

• Supplies blood to the anterior walls of Supplies blood to the anterior walls of both ventricles both ventricles

• Left circumflex artery (LCX) Left circumflex artery (LCX) • Supplies blood to the left atrium and the Supplies blood to the left atrium and the

posterior walls of the left ventricle posterior walls of the left ventricle

Basic Anatomy of the Basic Anatomy of the Coronary SystemCoronary System

Coronary Artery DiseaseCoronary Artery Disease

• Arteries that supply blood and oxygen to Arteries that supply blood and oxygen to the heart muscle become clogged by the heart muscle become clogged by plaque.plaque.

• Plaque is the build-up of fat, cholesterol Plaque is the build-up of fat, cholesterol and other substances in the artery walls and other substances in the artery walls

• Plaque build-up over time: Plaque build-up over time: atherosclerosis atherosclerosis

Coronary StenosisCoronary Stenosis• A narrowing or constriction of the A narrowing or constriction of the

diameter of a bodily passage or orifice.diameter of a bodily passage or orifice.

Coronary Artery Coronary Artery DiseaseDisease

• Who is at Risk?Who is at Risk?• Both men and women Both men and women • High cholesterol levels High cholesterol levels • High blood pressure High blood pressure • Diabetes Diabetes • A diet too high in saturated fatA diet too high in saturated fat• ObesityObesity• Too much stressToo much stress• Lack of exercise Lack of exercise • Cigarette smoke intake Cigarette smoke intake • Family history of coronary artery disease Family history of coronary artery disease

Coronary Artery Coronary Artery DiseaseDisease

• EffectsEffects• Angina (chest pain)Angina (chest pain)• Dyspnea (shortness of breath)Dyspnea (shortness of breath)• Coronary Heart Disease (CHD)Coronary Heart Disease (CHD)• Ischemia (decreased blood flow to the Ischemia (decreased blood flow to the

heart muscle)heart muscle)• Arrhythmia (irregular heart beat) Arrhythmia (irregular heart beat) • Myocardial Infarction (heart attack)Myocardial Infarction (heart attack)

Coronary StentsCoronary Stents

• A tiny coil or A tiny coil or mesh tube that is mesh tube that is inserted into the inserted into the clogged coronary clogged coronary artery to form a artery to form a rigid support rigid support which holds the which holds the artery open.artery open.

Coronary StentsCoronary Stents

• Types of StentsTypes of Stents

• Mechanism of expansionMechanism of expansion

• CompositionComposition

• DesignDesign

Coronary StentsCoronary Stents

• Mechanism of expansionMechanism of expansion• Balloon expandableBalloon expandable

• Stainless steel coil tube Stainless steel coil tube • Mounted on balloon catheterMounted on balloon catheter• Positioned at the stenosis site Positioned at the stenosis site • Stent expands with balloonStent expands with balloon

Coronary StentsCoronary Stents

Coronary StentsCoronary Stents

• Self-expandableSelf-expandable • Placed over a guide wirePlaced over a guide wire• Positioned at the stenosis sitePositioned at the stenosis site

• Cover is retracted Cover is retracted • Self-expands and locks into placeSelf-expands and locks into place

Coronary StentsCoronary Stents

• Composition Composition • Stainless steelStainless steel• NitinolNitinol• Cobalt-based alloyCobalt-based alloy• TantalumTantalum

Coronary StentsCoronary Stents

• Stainless SteelStainless Steel• AdvantagesAdvantages

• Small size of the whole system Small size of the whole system (guidewire, stent, and balloon) (guidewire, stent, and balloon)

• Ability to fit into twisting vessels Ability to fit into twisting vessels

• DisadvantagesDisadvantages• Difficulty in seeing them while positioningDifficulty in seeing them while positioning• Difficulty in determining their final length Difficulty in determining their final length

upon expansion upon expansion

Coronary StentsCoronary Stents

• Nitinol Nitinol (Nickel Titanium Naval Ordinance (Nickel Titanium Naval Ordinance Laboratory)Laboratory)

• A family of intermetallic materials that A family of intermetallic materials that contain a nearly equal mixture of nickel contain a nearly equal mixture of nickel and titaniumand titanium

• High degree of elasticity High degree of elasticity • Shape memory Shape memory

Coronary StentsCoronary Stents

• DesignDesign• Coil designCoil design

• Flexible Flexible

• Tubular designTubular design • More support More support

Express² Stent SystemExpress² Stent System

Alterative Procedures and Alterative Procedures and DevicesDevices

• AngioplastyAngioplasty• A medical procedure in which a A medical procedure in which a

balloon is used to open narrowed or balloon is used to open narrowed or blocked blood vessels of the heartblocked blood vessels of the heart

• Unevenly expands balloon against the Unevenly expands balloon against the sides of the artery lumesides of the artery lumenn

• Produces a rough, irregular channel Produces a rough, irregular channel and and a rough surface a rough surface

Alterative Procedures and Alterative Procedures and DevicesDevices

Alterative Procedures and Alterative Procedures and DevicesDevices

• Coronary Artery Bypass Graft (CABG)Coronary Artery Bypass Graft (CABG)• Creates new routes around narrowed and blocked Creates new routes around narrowed and blocked

arteriesarteries• Saphenous vein, sewn to the coronary artery Saphenous vein, sewn to the coronary artery

beyond the narrowing or blockage, other end is beyond the narrowing or blockage, other end is attached to aorta attached to aorta

• Advantage: Advantage: • Multiple narrowings in multiple coronary artery branchesMultiple narrowings in multiple coronary artery branches• People who are not good candidates for balloon People who are not good candidates for balloon

angioplastyangioplasty

• Disadvantage: Very invasive procedure Disadvantage: Very invasive procedure

Alterative Procedures and Alterative Procedures and DevicesDevices

How to Prevent How to Prevent StentingStenting

• ExerciseExercise

• Healthy DietHealthy Diet