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ATHEROSCLEROSIS

Spring 2005

Arteriosclerosis is the process of the hardening of the arteries. Atherosclerosis is a specific type of arteriosclerosis. Atherosclerosis is the accumulation of lipids in the walls of the arteries. This process leads to a hardening of the arteries.

The primary sites of atherosclerosis are the coronary arteries, cerebral arteries, and femoral artery; exhibiting coronary heart disease, cerebrovascular disease, and peripheral vascular disease.

Together, coronary artery disease and cerebrovascular disease are the leading causes of death in the United States, accounting for 41% of mortality.

 
Arterial Damage

 

NATURAL HISTORY OF ATHEROSCLEROSIS

The atherosclerotic process is associated with the aging process. Having been documented in the autopsies of ancient mummies, atherosclerosis appears to be universal in humans troughout the history of mankind. This natural history can be documented in every human.

 The natural history of atherosclerosis begins at birth. The arteries are patent and clean at birth.

By the age of 10 years old, the walls of the arteries will appear streaked with lipid deposites called Fatty Streaks.

The fatty streaks continue to develop in early adulthood until they protrude into the lumen of the artery and become Fibrous Plaque.

 

  

 In middle-age, the fibrous plaque invades a large part of the artery, damaging the artery to the extent of precipitating a clinical event. This stage of the disease is called Clinical Lesion.

PHASES OF THE NATURAL HISTORY OF ATHEROSCLEROSIS
Phase
Charactertics
Fatty Streaks  
Fibrous Plaque  
Complicate Lesion  
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ARTERIAL INFLAMATION

Arterial health is the key to preventing atherosclerosis. Endothelial function is the key to arterial health. The inflamatory process illustrated below describes the basic steps in the etiology of heart disease, cerebrovascular disease and peripheral vascular disease.
 
 
 
 
 
 
 
 
Arterial Damage

The atherosclerotic process can damage the artery in several ways. Each way ends up as a damaging event in the artery.
 

 
   
   

 

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PATHOPHYSIOLOGY OF ATHEROSCLEROSIS

Ischemia and infarct are the direct result of atherosclerosis. Ischemia is low blood flow. Infarct is death of tissue resulting from lack of blood flow. Both the ischemia and infarct are exhibited in different ways in the various end organs of atherosclerosis. The series of slides below illustrate ischemia and infarct in the heart.

 

Ischemia and infarction can occur in any organ. The primary arteries and organs affected by atherosclerosis are the

  • coronary arteries and the heart
  • cerebral arteries and the brain
  • femoral arteries and the legs

The table below summarizes the signs and symptoms of ischemia and infarct in these tissues.

ISCHEMIA AND INFARCT IN TARGET TISSUES
Arteries
Organ
Disease
Ischemia
Infarct
Coronary
Heart
  • Coronary Artery Disease
  • Heart Disease
 Angina Myocardial Infarction
Cerebral
Brain
 Cerebrovascular Disease Transient Ischemic Attack Cerebral Vascular Accident
Femoral
Legs
 Peripheral Vascular Disease Claudication Gangrene

To view additional illustrations of the influence of ischemia & infarct in the target tissues, click below

Atherosclerosis also affects the supply and demand of the myocardium. Understanding the balance of blood supply and work demand will help explain the actions of medications and exercise in the treatment of heart disease.

 

 

HOW ISCHEMIA & INFARCT AFFECT THE PERFORMANCE OF THE HEART
 

 
   

Cardiac tests to diagnose ischemia and infarct are

  • Thallium
  • Technicium
  • Echo
  • Dobutamine

 
   
Arterial Damage
HOW ISCHEMIA AND INFARCT AFFECT THE BRAIN

Ischemia and infarct of the brain is dependent on what area of the brain is involved.

The figure to the left illustrates the functions of the various area of the brain.

Ischemia or infarct in those areas results in a compromise or loss of that specific function.
 
The arterial tree dictates which area of the brain is perfused.

The specific loss of function depends on not only which artery is affected, but the location of the atheroma.

The closer the athroma is to the base of the artery, the larger the stroke and the more function is lost.

If the atheroma is in the smaller arteries, the size of the stroke is smaller and the extent of the functional loss is limited.

General characteristics of right and left sided strokes are summarized below.

 
Left Sided Stroke Right Sided Stroke
  • Physical
    • Right hemiplegia
  • Cognitive
    • Aphasia
    • Agraphia
    • Alexia
    • Ataxia
    • Memory impairments
    • Confabulation, attentional deficits
  • Emotional
    • Lability
    • Low tolerance
    • Depression (more common with right CVA)
  • Assisting the Patient with a Left CVA
    • Speak slowly!
    • Learn to recognize nonverbal cues from the patient
    • Let patient learn through imitation
  • Physical
    • Left hemiplegia
  • Cognitive
    • Difficulty with time and space,
    • Increased perceptual problems
    • Decreased ability to recognize faces
    • Decreases mathematical and reasoning skills
    • Decreased eye-hand coordination
  • Emotional
    • Lability
    • Low tolerance
    • Depression
    • Denial
  • Assisting the Patient with a Left CVA
    • Emphasize verbal cues
    • Use visual fields appropriately
    • Keep everything related to safety on the right!!!!!
    • Decrease stimuli
    • Break tasks into small steps

 

Arterial Damage

This page was last updated 18 January, 2005
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Webmaster: Janet P. Wallace, PhD, FACSM
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