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Unit VI Promoting Health in Patients With Circulatory or Perfusion Disorders
Tunica adventitia
Tunica media
Tunica intima
Smooth muscle
Endothelium
Basement membrane
Internal elastic membrane
External elastic membrane
FIGURE 30.1 Layers of the arterial wall.
Artery cross section
Normal artery
Endothelium
Normal blood flow
Artery wall
Narrowing artery
Atherosclerotic plaque
Damaged endothelium
FIGURE 30.2 A comparison of a normal artery with an artery narrowed by atherosclerotic plaque deposits on the wall.
Abnormal blood flow Atherosclerotic plaque
Narrowed artery
an imbalance between supply and demand of oxygen-rich blood to the heart tissue, resulting in insufficient oxygen to meet the demands of the myocardial tissue . Infarction, or cell death, occurs when that imbalance is severe or pro- longed, which causes irreversible damage. The primary patient complaint is chest pain, also called angina . Angina is classified into two categories, stable and unstable angina. Stable angina is chest pain or discomfort that is asso- ciated with physical activity. It is typically linked to fixed
plaque formations and is predictable. Symptoms of stable angina are often alleviated with rest and/or medications. Nitrates such as nitroglycerin that dilate the coronary arteries, improving oxygen-rich blood flow to the heart, are typically prescribed for angina. Unstable angina refers to chest pain that can occur at rest. Of the two types of angina, unstable angina is the most concerning. It is usually prolonged and may not be relieved with rest or medication. It can be a precursor to
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