Cardiomyopathies Flashcards
Most Common Cardiomyopathy
Dilated (congestive) Cardiomyopathy (DCM)
Findings of DCM:
S3, Dilated heart on ultrasound, balloon appearance on chest x-ray
Dilation in DCM Leads to
- Impairment of contractility, or hypocontraction.
- Hypocontraction and stasis predispose to mural thrombi.
Causes of DCM (Major Causes)
ABCCCD
- Alcohol Abuse
- wet Beriberi
- Coxsackie B virus myocarditis
- chronic Cocaine use
- Chagas’ Disease
- Doxorubicin toxicity
Uncommon causes of DCM
Hemochromatosis and Peripartum Cardiomyopathy
DCM Type of Dysfunction
Systolic Dysfunction
Complication of Hypertrophic Cardiomyopathy
Hypertrophied interventricular septum is “too close” to the mitral valve leaflet, leading to outflow tract obstruction
Major Cause of Hyperthrophic Cardiomyopathy and association
- Familial, autosomal dominant Beta-myosin heavy chain mutation that affects Sarcomere Proteins
- Friedreich’s Ataxia
DCM Treatments
Sodium Restriction, ACE Inhibitors, Diuretics, Digoxin, and Heart Transplant
Histologic Feature of Hypertrophic Cardiomyopathy
- Disoriented, tangled, and hypertrophied myocardial fibers
- Asymmetric ceoncentric hypertophy of myocytes (sarcomeres added in parallel)
Mitral Valve Leaflet Outflow Obstruction Leads to
Systolic Murmur and Syncopal Episodes
Hypertrophic Cardiomyopathy Findings
- Normal Sized Heart, S4, apical impulses, and systolic murmur
- LV “Banana-like configuration” due to bulging septum
How does HCM affect Stroke Volume
- Decreased Stroke Volume and Increased Afterload due to impaired diastolic filling and LV outflow tract obstruction = Decreased Cardiac Ouput
HCM Type of Dysfunction
Diastolic
Major Causes of Restrictive Cardiomyopathy (RCM)
Sarcoidosis, Amyloidosis, Postradiation Fibrosis, Endocardial Fibroelastosis, Loffler’s Syndrome, and hemochromatosis
What is found in endocardial fibroelastosis?
Thick Fibroelastic tissue in endocardium of young children
What is Loffler’s Syndrome?
EndoMYOCARDIAL fibrosis with a prominent EOSINOPHILIC infiltrate.
EKG Findings of RSM
Low voltage and Diminished QRS Amplitudes
Fibrosis in RSM Leads to
Restriction of ventricular filling leading to reduced cardiac output
Approximately 1/3 of DCM are genetic. The majority of these are due to mutations in what? and what is the inheritance?
- Mutations of cardiac myocyte cytoskeletal proteins (dystrophin) or mitochondrial enzymes.
- Autosomal Dominant.
