Myocarditis and Cardiomyopathy Flashcards
What is acute myocarditis
acute inflammation of cardiac muscle usu viral etiology
what is the typical etiology of acute myocarditis
viral
myocarditis focal or diffuse
BOTH FOCAL AND DIFFUSE
types of patients who can present with acute myocarditis
healthy young adults and children
types of preceding symptoms in acute myocarditis
50% have preceding respiratory/GI symptoms within 2 weeks
common symptoms of Acute myocarditis
fever
chest pain with ECG changes (due to concurrent pericarditis)
arrhythmia (w/ or w/o palp or syncope)
Heart failure (adults)
what symptoms of acute myocaridtis can have high mortality
low ejection fraction
heart failure
but can recover and develop chronic dilated cardiomyopathy
Myocarditis is often ____
an autoimmune reaction due to coxsackie B virus with similar immunologically to cardiac myosin
Physcial exam in acute myocarditis
S3
pulm congestion/edema
mitral regurgitation
incr troponin
global ventricular dysfunction ECG
Most common type of cardiomyopathy
dilated cardiomyopathy
which chambers involved in dilated cardiomyopathy
LV always but usu all 4 chambers
three types of cardiomyopathy
1) dilated
2) hypertrophic
3) restrictive
part of heart affected in HCM
LV hypertrophied NOT DILATED
hypertrophy of IV septum
muscle fiber and collagen disorganized
part of heart affected in restrictive cardiompathy
infiltration/fibrosis of ventricles NO DILATION
PRESENTATION OF DILATED CARDIOMOPATHY
heart failure with
1) large silent heart
2) impaired systolic function (poor contract LV)
etiology of dilated cardiomyopathy
1) usually idiopathic
2) genetic, viral, ischemic
dilated cardiomyopathy on CXR
1) enlarged heart (cardiomegaly)
2) congested lung field
dilated cardiomyopathy on ECHO
both ventricle dilated and more spherical
diffuse poor wall motion
low ejection fraction
other clinical effects of dilated cardiomyopathy
1) arrhythmia- injury, fibrosis, dilation - atrial fibrillation, ventricular arrhythmia
2) thromboembolism from ventricle- dilation, poor contraction, abnormal surface
effects of angiotensin II
1) vasoconstriction
2) incr aldosterone release
3) Na+ reabsorption
4) fibrosis
5) incr sympathetic activity
6) hypertrophy
lab test elevated in patients with CHF but not asymptomatic LV dysfunction
BNP
TREATMENT FOR DILATED CARDIOMYOPATHY
–> TREATING HEART FAILURE1
1) DIURETICS
2) ace inhibitors
3) beta blocker
4) aldosterone antag
5) vasodilator
6) inotrope
7) LVAD, transplant
other treatments beside treating heart failure for dilated cardiomyopathy
1) anticoagulation
2) anti arrhythmic (drug, ICD)
3) anti-infalmmatory, immunosuppressive
what is hypertrophic cardiomyopathy
eccentric hypertrophy involving IV septum NO DILATION
what is dysfunctional in HCM
diastolic dysfunction
dynamic (aortic) outflow obstruction
NORMAL OR INCR SYSTOLIC FUNCTION
inheritance of HCM
autosomal dominant
what happens strcuturally HCM WITHOUT AORTIC OUTFLOW DYSFUNCTION
diastolic dysfunction due to
1) impaired diastolic relaxation
2) incr stiffness
1) incr LV diastolic pressure
- -> incr pulm venous/capillary pressure
usual symptom of HCM WITHOUT AORTIC OUTFLOW OBSTRUCTION
dyspnea on exertion
not susceptible to sudden death
WHAT HAPPENS in HCM obstructive
1) asymmetric myocardial hypertrophy
2) diastolic dysfunction
3) incr systolic dysfunction
4) dynamic LV outflow obstruction
MITRAL VALVE PARTIALLY BLOCKS OUTFLOW TRACT
BELOW AORTIC VALVE during mid-late systole
–> syncope/SUDDEN DEATH
clinical manifestation of HCM obstructive
VARIABLE
1) dyspnea – incr LV filling P
2) angina- hypertrophic LV, incr systolic LV P
3) sudden death- arrhythmia
why is there dyspnea in HCM obstructive
incr LV filling pressure
why is there angina in HCM obstructive
hypertrophic LV
incr systolic LV pressure
treatment for HCM obstrcutive
1) avoid sports and extreme exerton
2) decr contractility with beta blockers/verapamil (decr outflow obstruct)
3) surgical myomectomy or alcohol ablation
4) ICD - ventricular pacing
restrictive cardiomyopathy is mostly caused by ___
infiltrative
amyloidosis
sarcoidosis
what happens in restrictive cardiomyopathy
decr ventricular filling due to stiff ventricles (NOT DILATED)
normal systolic fxn
how to diagnose restrictive cardiomyopathy
1) echo with doppler of ventricular filling
2) MRI
how to treat acute myocarditis?
1) ACE inhibitor
2) beta blocker to prevent remodeling
what age population is associated with sudden death from HCM?
what age assoc with stroke/heart failure
sudden death = young people up to age 40
stroke/heart failure = old people
histology of HCM
1) disorganized myocytes = reentry paths
2) remodeled coronary arteriole = impair coronary perfusion
3) replacement fibrosis
