Download Chapter 5: Age-Related Changes of the Cardiovascular System

Chapter 5: Age-Related Changes of the
Cardiovascular System
What You Will Learn
• Normal cardiovascular changes that occur with aging
• Risks associated with cardiovascular changes in the frail elderly
Author:
Key Terms
Carol Harrington RN, BC, ANP,
CDE, Adult Nurse
Practitioner, Kansas City
Internal Medicine,
Kansas City, MO.
Atherosclerosis — An arterial disease in which plaques form on the inner surfaces of the arteries, obstructing blood flow
Atrophy — A wasting away; a reduction in the size of a cell, tissue,
organ, or part
Congestive Heart Failure (CHF) — A condition in which the heart cannot
pump enough blood to the body’s other organs, characterized by shortness of breath, abnormal peripheral circulation, or both, depending on
whether the heart failure is right-sided or general
Hypertrophy — The enlargement or overgrowth of an organ
Myocardium — The thick muscular wall of the heart
Pulmonary Embolism — A sudden blockage in a pulmonary artery due
to a blood clot or embolism, preventing the exchange of oxygen and carbon dioxide and decreasing blood supply to the lung tissue itself
Sinus Node — A small mass of specialized cardiac muscle fibers in the
wall of the right atrium of the heart that originate the regular electrical
impulses that stimulate the heartbeat
Heart disease is the leading
cause of hospitalization and death
in the elderly.
Although the size of the heart does not change with normal aging,
several age-related changes in the cardiovascular system reduce the efficiency of the heart. In addition, the existence of heart disease so commonly treated in the elderly causes significant changes in the structure
of the heart muscle.
The myocardium may atrophy (shrink) or hypertrophy (enlarge). Both
changes are worsened by inactivity or disease processes, such as hypertension. These conditions will progressively worsen with time. Changes
to the myocardium’s thickness and shape affect the function of the heart
valves as well. With normal aging, the heart muscle slowly loses its efficiency and contractile strength resulting in a decreased cardiac output.
There is also a reduction in the number of pacemaker cells in the FENCE Student Manual
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sinus node. This reduction changes
the electrical timing or rhythm of
the heart. These changes affect the
time needed for the chambers of the
heart to fill during diastole, the resting phase, and to eject blood during
systole, the contracting phase.
In general, the heart rate of an older person does not rise in response
to fever or stress in the same manner as it does in a younger adult.
Pulmonary
Artery
Aorta
Left
Atrium
Right
Atrium
Aortic
Valve
Left
Ventricle
The prolonged normal heart cycle
results in a reduced exercise capacity in older adults. Most older adults
adapt to this by subconsciously
Pulmonary
Right
Valve
recognizing the need to reduce their
Ventricle
activity, such as choosing to take an
elevator rather than the stairs. The
Figure 5.1. Cardiovascular System.
reduction in heart rate also results
in an ineffective response to stress
or fever. In general, the heart rate of an older person does not rise in response to fever or stress in the same manner as it does in a younger adult.
When unusual demands are placed on the heart by sudden exertion or
emotional stress, the heart may not be able to meet the demand.
When the need for increased cardiac output cannot be attained by increased contractility, the heart compensates by increasing blood pressure
or heart rate. If tachycardia develops, it may progress to heart failure. The
increased oxygen demand of the myocardium may also be impaired, risking damage to the heart muscle.
The arteries consist of three layers, each of which is affected differently by
aging. The inner layer, called the tunica intima, is most directly changed.
Calcium and lipids build up contributing to atherosclerosis. This accumulation causes the lumen of the artery to narrow resulting in diminished
blood flow.
The outer layer, the tunica adventitia, is not affected by the aging
process.
The elastic fibers of the middle layer, the tunica media, become thin and
calcified causing it to stiffen. This leads to a rise in systolic blood pressure.
There is a reduced sensitivity of the receptors that regulate blood pressure. This results in increased risk for postural or orthostatic hypotension.
The blood vessels of the head,
neck, and extremities are more
prominent in the elderly. This is
due to a loss of subcutaneous fat
as well as reduced elasticity in
the vessels.
The veins also lose elasticity. Due to reduced activity in older adults, the
pumping action usually caused by muscle motion of the calf muscles is
lessened. The veins dilate causing pooling of blood in dependent areas,
such as the lower legs and feet, leading to edema.
FENCE Student Manual
In addition, age related changes in the cardiovascular system may alter the
signs and symptoms of heart disease in the elderly. Responses to dramatic
changes in the body may be slowed or not clearly identifiable. Heart attack, congestive heart failure, and pulmonary embolism may all present
with a sudden onset of confusion rather than pain or difficulty breathing.
Further assessment is needed when changes in behavior or normal function are noted.
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Chapter 5 Review Questions
Define the following terms:
1. Atherosclerosis —
2. Atrophy —
Answer the following multiple choice question:
12. In an older person, the first sign of a heart
attack may be:
a. Complaints of fatigue
b. Edema in the legs and feet
c. Low blood pressure
3. Congestive Heart Failure: (CHF) —
4. Hypertrophy —
5. Myocardium —
d. Sudden onset of confusion
Complete the following:
13. The leading cause of death in adults is
______________________________.
14.With aging, the heart rate usually
_____________________.
6. Pulmonary Embolism (PE) —
7. Sinus Node —
Circle “True” or “False” as appropriate for the
following statements:
8. (True/False) — With normal aging, the heart
muscle slowly loses its efficiency and contractile strength resulting in a decreased cardiac
output.
9. (True/False) — The heart rate of an older person rises in response to fever or stress more
quickly than it does in a younger adult.
10. (True/False) — With aging, the veins lose
elasticity and dilate, causing pooling of blood
in dependent areas, such as the lower legs
and feet.
11. (True/False) — The young and old present
with similar symptoms with a heart attack.
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