Pathophysiology of Cardiomyopathies Flashcards
Cardiomyopathies
heterogenous group of disease of the myocardium, associated with mechanical and/or electrical dysfunction. Often see ventricular dilation or hypertrophy. Often leads to progressive heart failure or fatal arrhythmias
Primary cardiomyopathy
disease of the myocardium of idiopathic cause. Can be acquired or genetic
Secondary cardiomyopathy
myocardial involvement as part of a known systemic disorder, like CAD, congenital heart disease, htn, etc.
5 major phenotypes of pediatric cardiomyopathies
- hypertrophic.
- Dilated.
- restrictive.
- Left Ventricular noncompensation.
- arrhythmogenic right ventricular.
molecular pathway genetic defects associated with cardiomyopathies
Contractile proteins, like myosin and actin, intracellular calcium handling and myocardial energetics proteins, like actin and myosin.
Gold standard for diagnosing cardiomyopathy
echocardiogram.
Can also do ECG and CXR
Hypertrophic cardiomyopathy
Defined as the presence of unexplained left ventricular hypertrophy, primary myocardial process, with myocyte disarray and fibrosis. Fibrosis is not specific but is one of the final pysiologies of HCM
In adults, HCM diagnosis implies a ___ gene mutation
Sarcomeric gene mutation
HCM inheritance
typically autosomal dominant, affecting over 27 genes
non-genetic causes of pediatric HCM
rarely occur; LVH can occur in response to some environmental triggers, such as transient LVH in infants and diabetic mothers.
Pediatric HCM risk is greatest for
if you present as an infant, if you present with an inborn error of metabolism, or if it is mixed with other pathologies like DCM
testing for pediatric HCM
cascade cardiac screening and genetic testing.
Restrictive cardiomyopathy, RCM
rare, characterized by diastolic dysfunction but intact systolic dysfunction until later stages of the disease. Have marked atrial enragement, but normal atrial wall thickness.
Pediatric RCM
has the worst prognosis. majority of the cases are idiopathic, but there is new evidence that shows denovo mutations in titin to be a factor in familial RCM.
Dilated Cardiomyopathy, DCM
characterized by left ventricular dilation and systolic dysfunction. Overall poor prognosis
Pediatric DCM
most common form of cardiomyopathy. Most genetically heterogenous of all cardiomyoathies, and all mendelians patterns of inheritance are represented.
DCM is predominantly caused by mutations in genes encoding what?
cystoskeletal and sarcomeric proteins
