Transcript Stents - Oregon Institute of Technology

Coronary Stents
RDSC 326
Basic Anatomy of the Coronary
System
• Right coronary artery (RCA)
• Originates above right cusp of the aortic
valve, travels down right atrioventricular
groove, towards the crux of the heart
• Right marginal artery
• Supplies blood to the right side of the heart
• Posterior descending artery (PDA)
• Supplies blood to the apex of the heart and the
posterior ventricular walls
Basic Anatomy of the Coronary
System
• Left coronary artery (LCA)
• Arises from aorta above left cusp of the
aortic valve
• Left anterior descending (LAD) artery
• Supplies blood to the anterior walls of both
ventricles
• Left circumflex artery (LCX)
• Supplies blood to the left atrium and the
posterior walls of the left ventricle
Basic Anatomy of the Coronary
System
Coronary Artery Disease
• Arteries that supply blood and oxygen to the
heart muscle become clogged by plaque.
• Plaque is the build-up of fat, cholesterol and
other substances in the artery walls
• Plaque build-up over time: atherosclerosis
Coronary Stenosis
• A narrowing or constriction of the diameter
of a bodily passage or orifice.
Coronary Artery Disease
• Who is at Risk?
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Both men and women
High cholesterol levels
High blood pressure
Diabetes
A diet too high in saturated fat
Obesity
Too much stress
Lack of exercise
Cigarette smoke intake
Family history of coronary artery disease
Coronary Artery Disease
• Effects
• Angina (chest pain)
• Dyspnea (shortness of breath)
• Coronary Heart Disease (CHD)
• Ischemia (decreased blood flow to the heart
muscle)
• Arrhythmia (irregular heart beat)
• Myocardial Infarction (heart attack)
Coronary Stents
• A tiny coil or mesh
tube that is inserted
into the clogged
coronary artery to
form a rigid support
which holds the
artery open.
Coronary Stents
• Types of Stents
• Mechanism of expansion
• Composition
• Design
Coronary Stents
• Mechanism of expansion
•Balloon expandable
• Stainless steel coil tube
•Mounted on balloon catheter
•Positioned at the stenosis site
•Stent expands with balloon
Coronary Stents
Coronary Stents
•Self-expandable
•Placed over a guide wire
•Positioned at the stenosis site
•Cover is retracted
•Self-expands and locks into place
Coronary Stents
• Composition
• Stainless steel
• Nitinol
• Cobalt-based alloy
• Tantalum
Coronary Stents
• Stainless Steel
• Advantages
• Small size of the whole system (guidewire,
stent, and balloon)
• Ability to fit into twisting vessels
• Disadvantages
• Difficulty in seeing them while positioning
• Difficulty in determining their final length
upon expansion
Coronary Stents
• Nitinol (Nickel Titanium Naval Ordinance Laboratory)
• A family of intermetallic materials that contain
a nearly equal mixture of nickel and titanium
• High degree of elasticity
• Shape memory
Coronary Stents
• Design
• Coil design
• Flexible
• Tubular design
• More support
Express² Stent System
Alterative Procedures and
Devices
• Angioplasty
• A medical procedure in which a balloon is
used to open narrowed or blocked blood
vessels of the heart
• Unevenly expands balloon against the
sides of the artery lumen
• Produces a rough, irregular channel and a
rough surface
Alterative Procedures and
Devices
Alterative Procedures and
Devices
• Coronary Artery Bypass Graft (CABG)
• Creates new routes around narrowed and blocked
arteries
• Saphenous vein, sewn to the coronary artery beyond
the narrowing or blockage, other end is attached to
aorta
• Advantage:
• Multiple narrowings in multiple coronary artery branches
• People who are not good candidates for balloon angioplasty
• Disadvantage: Very invasive procedure
Alterative Procedures and
Devices
How to Prevent Stenting
• Exercise
• Healthy Diet