EXAM #1: CARDIOMYOPATHY Flashcards
What is the definition of cardiomyopathy?
Myocardial disease that results in cardiac dysfunction
What is the definition of dilated cardiomyopathy?
Dilation of all four chambers of the heart
*Note that this is the most common
What is the definition of hypertrophic cardiomyopathy?
Massive hypertrophy of the LV that results in dysfunction and arrhythmia
What is the definition of restrictive cardiomyopathy?
Decreased compliance of ventricular endomyocardium that restricts filling during diastole
What is the most common etiology of dilated cardiomyopathy?
Idiopathic
What are the less common etiologies of dilated cardiomyopathy?
1) IHD
2) HTN
3) Alcoholic
4) Infectious (Chagas and coxsackie)
5) Metabolic
Describe the pathogenesis of dilated cardiomyopathy?
Dilated ventricles with thin walls lead to systolic dysfunction
What are the complications of dilated cardiomyopathy?
1) Biventricular CHF
2) Arrhythmia
3) Mitral/ tricuspid valve regurgitation
What are the symptoms of dilated cardiomyopathy?
LV failure:
- Fatigue
- Weakness
- Dyspnea (exertional, orthopenia, PND)
- Pallor/tachycardia
Describe the pathogenesis of orthopena in dialted cardiomyopathy.
1) Lay down= increase preload
2) Heart can’t hand preload
3) Back-up into lungs
= Orthopnea
What are the signs of LV failure?
- Tachycardia
- Cardiac apex is displaced left and down
- Apical lift/thrill
- S3*
- Mumurs
*S3 is UNIVERSAL in HF
What are the indications of dilated cardiomyopathy leading to biventricular failure?
Added sx. of RV failure:
- IMPROVED dyspnea (less filling to LV)
- Edema
- JVD
- S3 is UNIVERSAL
What is pulsus alternans?
Every other pulse is stronger in intensity
- Weak myofibrils cannot recover for each beat
- Full contraction occurs every other beat
What is cardiac cachexia?
B/c of RV failure and edema of liver, bowel, spleen etc…
- Limited intake
- Edematous bowel and liver don’t absorb and metabolism nutrients
How will dilated cardiomyopathy appear on Echo?
- Large dilated “baggy” heart
- V. limited ventricular wall motion in systole
What is alcoholic cardiomyopathy?
Dilated cardiomyopathy from direct alcohol myotoxicity
Note that alcohol causes cardiodepression in the absence of toxicity
What is a specific association with alcoholic cardiomyopathy?
A-fib/ arrhythmia
What do you need to be concerned about in terms of the lab evaluation of alcoholic cardiomyopathy?
- Blood alcohol levels
- Liver chemistry
- Hypovitaminoses
What is the treatment for alcoholic cardiomyopathy?
Patient MUST stop drinking
40-50% die within 3 years of diagnosis
What are the old names for hypertrophic cardiomyopathy?
IHSS
HOCM
HCM
What is the etiology of hypertrophic cardiomyopathy?
Genetic mutation in sarcomere proteins (autosomal dominant)
Macroscopically, how does the heart appear in Hypertropic Cardiomyopathy?
- Increased mass
- Asymmetric septal hypertrophy
- Concentric hypertrophy
- Apical hypertrophy
How does Hypertrophic Cardiomyopathy appear microscopically?
Myofiber hypertrophy with “disarray”
What is the average age of onset of Hypertrophic Cardiomyopathy?
26
This is a common cause of SUDDEN DEATH in young athletes.
What causes sudden death in hypertrophic cardiomyopathy?
Ventricular arrhythmias
What is a hallmark symptom of hypertrophic cardiomyopathy?
Syncope with exercise
What are the signs of hypertrophic cardiomyopathy?
- Displaced/ bifid LV
- Bisferiens carotid pulse
- S4
- Systolic murmur
What are the ECG characteristics associated with hypertrophic cardiomyopathy?
- Increased voltage in anterior leads
- ST and T-wave changes
- Q-waves inferior and lateral
- Ventricular arrhythmia
What study is diagnostic for hypertrophic cardiomyopathy?
Echo
What is the treatment for hypertrophic cardiomyopathy?
1) Reduce physical activity
- Catecholamines= arrhythmogenic
2) Beta-blockers
- Reduce contractility to limit obstruction
3) Myotomy/myectomy
What causes restrictive cardiomyopathy?
- Amyloidosis
- Sarcoidosis
- Endocardial fibroelastosis
- Loeffler Syndrome
- Hemochromatosis
How does restrictive cardiomyopathy present?
CHF with low-voltage ECG and diminished QRS amplitude
