17 - Dilated and Hypertrophic Cardiomyopathies Flashcards
The heart is an electrical-mechanical transducer
What does this mean?
The heart converts electrical signal into a mechanical signal
CAD
VHD
CM
CAD - Coronary artery disease
VHD - valvular heart disease
CM - cardiomyopathy
Arrythmias are _______
Arrhythmias are electrical problems/SCD (sudden cardiac death)
Define cardiomyopathy
Cardiomyopathies are a heterogeneous group of diseases of the myocardium associated with mechanical and/or electrical dysfunction that usually (but not invariably) exhibit inappropriate ventricular hypertrophy or dilation and are due to a variety of causes that frequently are genetic; affects the LV and RV
- are either confined to the heart or a part of generalized systemic disorders, often leading to CVD (cardiovascular death) or progressive heart failure-related disability
Cardiomyopathy is defined by a _______
Cardiomyopathy is defined by a pathologically abnormal myocardium
What are the four major types of cardiomyopathies?
- Dilated (DCM)
- Hypertrophic (HCM)
- Restrictive (RCM)
- Arrhythmogenic RV (ARVC)
Label the types of cardiomyopathies based on the phenotype
IMAGE SLIDE 7
The classic ventricular remodeling that occurs with HCM (hypertrophic cardiomyopathy) results in ____________
The classic ventricular remodeling that occurs with HCM (hypertrophic cardiomyopathy) results in a normal sized left ventricular cavity with thickened ventricular walls (concentric LVH) and preserved systolic function and marked diastolic dysfunction (HFpEF)
HFpEF = Heart Failure with preserved ejection fraction
IMAGE SLIDE 7
The classic remodeling that occurs with DCM (dilated cardiomyopathy) results in __________
The classic remodeling that occurs with DCM (dilated cardiomyopathy) results in a globular shape of the heart, thinning of the left ventricular walls (eccentric LVH), overall decrease in systolic function and MR (HFrEF)
HFrEF = heart failure with reduced ejection fraction
Label the image:
SLIDE 8
SLIDE 8
The cytoplasm of cardiomyocyte contains sarcomeres which contain _______ filaments. Mutations in sarcomear genes lead to _____ and _____. Why?
The cytoplasm of cardiomyocyte contains sarcomeres which contain thin and thick filaments. Mutations in sarcomere genes lead to DCM and HCM. Why?
- Mutations lead to an inappropriate transcriptional response to mechanical stress
- Many of these nuclear membrane genes also induce cardiac conduction system disease
- Mutations in sarcomere genes lead to an ___________
- Many of these nuclear membrane genes also induce __________
- Mutations in sarcomere genes lead to an inappropriate transcriptional response to mechanical stress
- Many of these nuclear membrane genes also induce cardiac conduction system disease
What are 8 different causes of hypertrophic cardiomyopathy
- Pressure-overloaded LV eg HTN and/or moderate/severe AS
- Genetic Hypertrophic Cardiomyopathy (Sarcomeric mutations)
- Anderson-Fabry Cardiomyopathy
- Glycogen Storage Diseases (eg PRKAG2
- Danon’s Disease (LAMP2 mutations)
- Mitochondrial CM (eg MELAS)
- Drug-induced CM (eg Hydroxychloroquine)
- Undiagnosed CM
IMAGE SLIDE 31
In DMC the ____ gene encoding the giant protein ____ is mutated
In DMC the TTN gene encoding the giant protein Titin is mutated.
Titin’s amino terminus anchors in the Z band and its carboxy terminus ends in the M band. Titin interacts with both the thin and thick filaments
