Cardiomyopathy Flashcards
Cardiomyopathy
- a group of conditions of the myocardium.
- myocardium becomes enlarged, thick, or rigid.
- In rare cases, it can be replaced with scar tissue
What happens as the myocardium progresses?
myocardium is weakened
What happens when myocardium gets weakened?
- The heart pumps less effectively, leading to heart failure.
- has difficulty maintaining normal electrical conduction, leading to arrhythmias.
- valvular disorders can develop.
What 3 groups are Cardiomyopathies classified into?
- dilated
- hypertrophic
- restrictive
What is Dilated Cardiomyopathy?
- Develops when the ventricles become enlarged and weakened
What heart chamber does Dilated Cardiomyopathy usually start?
-In the left ventricle and eventually affects the right ventricle
Describe what happens to the ventricle and wall thickness (of the heart)
The ventricles are enlarged (dilated) as a whole, but the wall thickness is normal or thin.
**Enlarged Ventricle
When the ventricle walls are stretched what happens to the contractility?
Cardiac contractility is weaker, resulting in systolic dysfunction.
What happens to the cardiac output when there is a systolic dysfunction?
- The cardiac output decreases
- Blood backs up into the pulmonary system
When cardiac output decreases and blood backs up into the pulmonary system, what can happen to the blood in the heart?
Blood can stagnate in the heart, causing thrombi to develop.
What is the risk for developing dilated cardiomyopathy?
- increases with age
- most common form of cardiomyopathy in children
- more common in African Americans and men
- idiopathic (most cases)
Dilated cardiomyopathy can be inherited, but secondary causes include?
- Chemotherapy (specifically doxorubicin and daunorubicin)
- Alcoholism
- Cocaine and amphetamine abuse
- Pregnancy, specifically the last trimester
- Infections, especially viral
- Thyrotoxicosis (hypermetabolic syndrome resulting from increased levels of thyroid hormones)
- Diabetes mellitus
- Neuromuscular diseases (e.g., muscular dystrophy)
- Hypertension
- Coronary artery disease
- Viral hepatitis
- Human immunodeficiency virus (HIV)
- Hypersensitivity to medications
- Certain toxins (e.g., poisons and heavy metals)
As dilated cardiomyopathy develops, the SNS and which organ attempts to compensate for the falling cardiac output?
- Kidneys
How do the SNS and kidneys compensate for the falling cardiac output (during the development of cardiomyopathy?
Increasing both the heart rate and the blood volume
The following clinical manifestations of dilated cardiomyopathy often develop insidiously:
Dyspnea Fatigue Nonproductive cough Orthopnea (difficulty breathing while lying down) Paroxysmal nocturnal dyspnea (difficulty breathing at night) Dysrhythmias Angina (cardiac chest pain that often occurs with exertion) Dizziness Activity intolerance Blood pressure changes Tachycardia Murmurs Abnormal lung sounds (e.g., crackles and wheezes) Tachypnea Peripheral edema Ascites (fluid in the peritoneal cavity) Weak pedal pulses Cool, pale extremities Poor capillary refill Hepatomegaly Jugular vein distention
Dilated cardiomyopathy affects only?
Systolic Function
Diagnostic procedures for dilated cardiomyopathy include?
echocardiogram EKG chest X-ray heart catheterization nuclear studies
Hypertrophic cardiomyopathy affects both
systolic and diastolic function
What increases the risk for developing Hypertrophic Cardiomyopathy?
- Hypertension
- obstructive valvular disease
- thyroid disease
With hypertrophic cardiomyopathy what part of the heart is most frequently affected?
The septum between the ventricles
***Enlarged Stiff Septum
During hypertrophic cardiomyopathy, what happens to the hypertrophied ventricle wall?
The hypertrophied ventricle wall becomes:
- Stiff
- Unable to relax during ventricular filling
What happens to the cardiac output when there is a reduction in ventricular filling?
- cardiac output decreases
With a reduction in ventricular filling, cardiac output decreases. What happens to the atrial and pulmonary pressures
atrial and pulmonary pressures increase
The hypertrophied myocardium compresses blood vessels, reducing?
- tissue perfusion
- causing ischemia
In addition to hypertrophy, the myocardium becomes ?
- Fibrotic
- Forms scars
When the myocardium forms scars, what happens to the electrical impulses of the heart?
They do not conduct electrical impulses properly, Arrhythmias can develop
Which population does Hypertrophic Cardiomyopathy
cause sudden cardiac death?
Young people, especially young athletes
Clinical manifestations of hypertrophic cardiomyopathy are similar to those associated with dilated cardiomyopathy:
- Dyspnea on exertion
- Fatigue
- Syncope
- Orthopnea
- Angina
- Activity intolerance
- Dysrhythmias
- Left ventricular failure
- Myocardial infarction
Hypertrophic Cardiomyopathy Treatment goals include?
- reducing ventricular stiffness
- improving ventricular filling
- enhancing cardiac output
- Beta-adrenergic blocking agents and calcium-channel blocking agents are often included in the medication regimen.
- Surgical removal of excess myocardium may be necessary for those patients who do not respond well to medications.
- Treatment of any dysrhythmias and hypertension may also be warranted.
What type of activity should be avoided to prevent sudden death that could be associated with hypertrophic cardiomyopathy?
strenuous activity (e.g., running)
Restrictive Cardiomyopathy (least common) is?
characterized by rigidity of the ventricles, but the myocardium does not thicken.
*****Walls of Ventricles become stiff
In Restrictive Cardiomyopathy what happens to the ventricles as a result of rigidity of the ventricles?
ventricles do not relax and fill
In Restrictive Cardiomyopathy when the ventricles do not relax and fill, what type of dysfunction does it lead to?
Diastolic Dysfunction
As restrictive cardiomyopathy progresses, what happens to the myocardium and the cardiac contractility?
- myocardium weakens
- cardiac contractility becomes ineffective
Causes of restrictive cardiomyopathy include the following conditions:
- Amyloidosis (buildup of fat and proteins in the heart muscle)
- Hemochromatosis (excessive amounts of iron in the heart)
- Radiation exposure to the chest
- Connective tissue diseases
- Buildup of scar tissue after a myocardial infarction
- Sarcoidosis (cellular growths on various organs)
- Cardiac neoplasms
Many cases are asymptomatic, but the following clinical manifestations may also appear with restrictive cardiomyopathy:
- Fatigue
- Dyspnea
- Orthopnea
- Abnormal lung sounds
- Angina
- Hepatomegaly
- Jugular vein distention
- Ascites
- Murmurs
- Peripheral cyanosis
- Pallor
