Cardiomyopathy Flashcards
Definition of cardiomyopathy
diseases of myocardium, affecting mechanical & electrical function of the heart
3 types of cardiomyopathy
hypertrophic
dilated
restrictive
HCM, and cause
marked ventricular hypertrophy in absence of abnormal loading conditions
Familial (AD) - 70% have mutations encoding b-myosin, a-tropomyosin and troponin T
HCM pathophysiology
hypertrophic non-compliant ventricles –> impairs diastolic filling –> reduced stroke volume + LV outflow tract obstruction (from asymmetrical septal hypertrophy
Compliance definiton:
how easily a chamber of the heart of the lumen of a blood vessel expands when its is filled with a volume of blood
HCM presentation
symptom free (detected by familial screening)
SOB, angina, syncope
sudden death = 1st manifestation
jerky carotid pulse, alpha wave in JVP
What would Ix for HCM show?
ECG: LVH pattern, AF
Echo & MR: small LV cavity + hypercontactile posterior wall
Genetic analysis
Management for HCM
Amiodarone: reduces risk of arrhythmia & sudden death
BBs and verapamil: chest pain
Implantable cardiac defibrillator (ICD)
Dilated cardiomyopathy
Dilated, flabby heart of unknown cause
Poor contraction
DCM associations
Congenital (X-linked, autosomal dominant, recessive)
Alcohol
AI
viral infection
DCM presentation
SOB, fatigue emboli (from mural thrombosis) pulmonary oedema arrhythmia (AF, VT) RVF
DCM Ix
Blood: plasma BNP (HF)
CXR: cardiomegaly, PE
ECG: tachycardia + other
Echo: dilated hypo kinetic heart + low ejection fraction
DCM Tx
Bed rest
Diuretics, digoxin, ACE-i, anti coat, biventricular pacing
ICD
cardiac transplant
Restrictive cardiomyopathy
Rigid myocardium = restricts diastolic filling
Causes of RCM
amyloidosis
idiopathic
