Transcript A Look Into Congestive Heart Failure

A Look Into Congestive Heart
Failure
By
Tim Gault
Definition
• Congestive heart failure (CHF) is a
condition in which the cardiac muscle does
not pump blood efficiently through the
circulatory system.
Causes
• The causes of congestive heart failure can
vary greatly.
• All forms of heart disease can lead to
heart failure
Primary Disorders
• Cardiomyopathy
• Heart muscle disorders cause the heart to
lose its contracting ability.
• Common conditions include coronary
atherosclerosis, arterial hypertension, and
inflammatory or degenerative muscle
disease.
Dysrythmias
• The heart cannot properly contract.
• Some of these conditions include
tachycardia, atrial dysrythmias, and
asynchronous contractions.
Systolic and Diastolic Heart Failure
• In diastolic dysfunctions of CHF the heart is
unable to relax and there is abnormal filling of
the ventricles.
• Systolic dysfunctions are due to the heart being
unable to create a force great enough to eject
blood normally.
• The left ventricle systolic dysfunction is the most
common cause of CHF, occurring in 60% of
patients
Secondary Disorder
• CHF can also be caused by other systemic
alterations such as an increase in metabolic
rate, hypoxia, hypoxemia, and anemia.
• These problems require the heart to increase
the cardiac output to meet the need for more
oxygen.
• This causes the heart to lose some of its oxygen
supply increasing the risk of CHF.
Pathogenesis
• The first problem that occurs in the heart is a lesion to
the heart muscle itself. This results in the heart being
unable to cause the correct amount of velocity for the
load placed on the heart.
• Once this occurs and cardiac output is decreased the
compensatory mechanisms kick in.
• These mechanisms include the sympathetic mechanism,
renin-angiotensin system, and ventricular hypertrophy.
• These mechanisms include the
sympathetic mechanism, renin-angiotensin
system, and ventricular hypertrophy.
• Sustains cardiac function for a while.
• Lead to a feed-back loop causing more
cardiac failure .
Symptoms
• A patient with CHF will notice several
different changes in their bodies.
• One of the most common signs of CHF is
swollen legs or ankles and difficult
breathing.
Signs
• The physician will listen to the heart for distinct
sounds that can indicate CHF.
• The patient might be tachycardic, pale in color,
have inspiratory rales, or heart murmurs.
• If the physician hears murmurs, it can indicate
that there is mitral or tricuspid regurgitation.
Diagnostic Tests
• Echocardiography: Most
useful test for diagnosis.
• Uses sound waves to see
a moving picture of the
heart.
• Able to distinguish
between systolic and
diastolic dysfunction.
• Cardiac Catheterization checks the
coronary arteries for atherosclerosis to see
if it is the cause of CHF.
• Exercise Stress Test gives an overall view
of how well your heart is performing under
stress.
Treatments for CHF
• Beta-blockers stop the sympathetic
nervous system from activating.
• This will prevent the release of
catecholamines, which in turn will reduce
heart rate, blood pressure, and
contractility.
• Calcium channel blockers: Help to control
the myocardial cells involved in pacing the
heart.
• The result of this agent is a decreased
heart rate, contractility, and causes
vasodilatation.
• Nitrates: Dilate the arteries and the veins in the
heart reducing the filling time for the ventricles
as well as increase cardiac output.
• Ace Inhibitors: Blocks the renin-angiotensin
mechanism.
• Improve mortality, heart failure symptoms, left
ventricle ejection fraction, as well as exercise
tolerance.
• Heart Rate Recovery (HRR)
• Experimental program which tries to
improve the heart rate in patients with
CHF.
• Short term aerobic exercise showed an
increase in the HRR in some patients that
were unable to exercise very well.
Outcome
• Patients who have heart failure
will have a low chance of
survival.
• 50% of patients with severe
heart failure will die within 12
months and those with
moderate CHF will die within
3-4 years.
• About 30-40% of patients will
die suddenly with CHF and
those with left ventricle
dysfunction have a mortality
rate of 10% per year.