Cardiomyopathy, Myocarditis, Pericardial Disease Flashcards
What is cardiomyopathy and what are the 3 types of cardiomyopathy?
Primary abnormality of the myocardium
- cardiac dysfunction not attributable to the pressure or volume overload
- primary disease of myocardium
- dilated cardiomyopathy
- hypertrophic cardiomyopathy
- restrictive cardiomyopathy
What is dilated cardiomyopathy? What do you see on a trichrome stain?
- most common
- contractile (systolic) dysfunction
- four chamber dilation
- 2-3 X normal weight
Trichrome stain:
myocyte hypertrophy and interstitial fibrosis
What are non-genetic causes of dilated cardiomyopathy?
- myocarditis
- peri partum
- toxic (e.g. alcohol)
- idiopathic
What are genetic causes of dilated cardiomyopathy?
cytoskeleton or mitochondria
–>defect in force generation, force transmission and or myocyte signaling
What does dilated cardiomyopathy lead to? How do you treat it?
progressive systolic congestive heart
- heart failure symptoms
- arrhythmias
- mural thrombi with embolic complications
Treat:
Medical therapy
Heart transplant
What is hypertrophic cardiomyopathy? What does it lead to?
Idiopathic hypertrophic subaortic stenosis (IHSS)
Hypertrophic obstructive cardiomyopathy (HOCM)
1. marked LV myocardial hypertrophy
-septum>free wall hypertrophied –>banana shaped LV cavity
Leads to:
- abnormal diastolic filling
- left ventricular outflow obstruction
- septal hypertrophy
- anterior mitral valve leaflet contacts ventricular septum
What does hypertrophic cardiomyopathy look like histologically?
hypertrophied myocytes
haphazard pattern
interstitial fibrosis
What are the causes of hypertrophic cardiomyopathy?
100% genetic causes
- autosomal dominant
- variable expression
- mutation in genes that encode proteins of sarcomeres
What are some outcomes to hypertrophic cardiomyopathy? What are the treatments?
- diastolic heart failure
- exertional dyspnea
- harsh systolic ejection murmur
- anginal pain
- intractable heart failure
- arrhythmias-some have defib put in becuase can go into fatal arrhythmias
- SUDDEN DEATH IN YOUNG ATHLETES
Treatments:
Medical therapy enhancing ventricular relaxation
Surgical excision of muscle
What is restrictive cardiomyopathy?
primary decrease in ventricular compliance
- firm/stiff myocardium
- ability to expand markedly limited
- impeded left ventricular filling during diastole
- systolic function preserved
- LV cavity size normal
What could cause restrictive cardiomyopathy?
idiopathic, radiation fibrosis, amyloidosis (amyloid build up), sarcoidosis (granulomas), inborn errors of metabolism, endocardial fibroelastosis, loeffler endomyocarditis (eosinophilia)
What is an amyloid?
misfolded proteins deposits in extracellular space causes tissue damage multiple proteins can deposit as amyloid Common features: 1. beta pleated sheet configuraion 2. congo red staining in tissue -apple green under polarized light
What is myocarditis?
inflammatory process resulting in myocardial injury
What are infectious ways of getting myocarditis?
Viruses
- Enterovirus- Coxsackie A and B
- most common etiology in US*** - cytomegalovirus
- HIV
Bacteria
- Diphtheria
- Borrelia burgdorferi-Lyme disease
Parasites
- Trypanosoma cruzi (Chaga’s disease)
- endemic in areas of south africa - trichinosis
- toxoplasmosis
What are noninfectious ways of getting myocarditis?
Immune mediated
- Hypersensitivity reactions
- drugs - Rheumatic fever
- Giant cell myocarditis
- sarcoidosis
What are clinical manifestations of myocarditis and what can it lead to?
- Asymptomatic or nonspecific symptoms-fever, fatigue
Lead to
-Congestive heart failure
-Acute congestive heart failure
-arrhythmias
-progression to dilated cardiomyopathy-virus resolves itself but still ongoing inflammatory injurty in heart
What can fill a pericardial effusion? What does a slow effusion do? What happens with a fast effusion?
clear yellow serous fluid-severe heart failure, blood-trauma or malignancy, or pus-bacterial
Slow: may not be clinically significant, globular enlargement of heart on CXR
Rapid: compress atria and vena cava, compress ventricles, restrict cardiac filling, cardiac tamponade
What is pericarditis? What causes it?
- inflammation of pericardium
- usually secondary to cardiac, thoracic, or systemic process
What is fibrinous pericarditis?
- irregular shaggy pericardial surface
-acute viral pericarditis
-uremia
-acute rheumatic fever
(bread and butter)
exam:
pericardial friction rub
What is suppurative (fibrinopurulent) pericarditis?
acute bacterial infection
- extension
- seeding
- Neutrophils
What causes hemorrhagic pericarditis?
Tb
Maligancy
What causes caseous pericarditis?
Tb
What symptoms are seen with pericarditis?
- silent
- chest pain
- systemic complaints
- friction rub
- EKG changes (diffuse ST elevation)
What can happen in healing of pericarditis?
- -Focal plaque-like thickening
- Mild adhesions
- constrictive pericarditis
What is constrictive pericarditis? How is it treated?
- pericardial space obliterated
- heart surrounded by dense scar
- diastolic expansion limitied-reduced cardiac output
- Tb, suppurative
Treatment
-Pericardiectomy
How are heart biopsies obtained?
biotome inserted transversely into right side of heart
-septal endomyocardial biopsied
