Cardiomyopathy Flashcards
Define the term cardiomyopathy
Refers to a disease of the heart muscle that cannot otherwise be explained by common cardiovascular diseases or congenital heart disease e.g. coronary artery disease, hypertension, valvular disease and congenital heart disease
How many people are affected by cardiomyopathies in the UK
About 1 in 500 of the UK population
What are the three main types of cardiomyopathies
- Hypertrophic cardiomyopathy (HCM)
- Dilated cardiomyopathy (DCM)
- Arrhythmogenic cardiomyopathy (AMC)
Define hypertrophic cardiomyopathy (HCM)
Genetic condition characterised by the disorganised arrangement of the myocardium causing thickening of the myocardium
What are the two changes characterised by hypertrophic cardiomyopathy (HCM)
Myocardial cells lies in disorganised, jumbled layers
Scarring of myocardium making the heart muscle stiff
When does hypertrophic cardiomyopathy usually develop
Usually develops after puberty
What are the 4 types of thickening pattern seen in hypertrophic cardiomyopathy (HCM)
- Asymmetrical septal hypertrophy without obstruction
- Asymmetrical septal hypertrophy with obstruction
- Symmetrical hypertrophy (also known as concentric hypertrophy)
- Apical hypertrophic cardiomyopathy
Asymmetrical septal hypertrophy without obstruction is a pattern of hypertrophic cardiomyopathy.
What is it characterised by
Characterised by myocardial thickening of the septum
Does not restrict the normal flow of blood out of your heart through the left ventricular outflow tract
Asymmetrical septal hypertrophy with obstruction is a pattern of hypertrophic cardiomyopathy.
What is it characterised by
Characterised by myocardial thickening of the septum and this thickening obstructs the flow of blood through the left ventricular outflow tract when the heart contracts
When the heart contracts, the mitral valve touches the septum causing mitral regurgitation
Symmetrical hypertrophy is a pattern type of hypertrophic cardiomyopathy.
What is it characterised by
Hypertrophy which is evenly distributed through the left ventricle
Apical hypertrophy is a pattern type of hypertrophic cardiomyopathy.
What is it characterised by
Hypertrophy is predominantly at the apex
Which valve is between the right atrium and the right ventricle
Tricuspid
Which valve is between the right ventricle and the lungs
Pulmonary valve
Which valve is between the left artium and the left ventricle
Mitral valve
Which valve is between the left ventricle and the peripheries
Aortic valve
How is hypertrophic cardiomyopathy diagnosed
Electrocardiogram (ECG) and echocardiogram (ECHO)
Name some of the clinical features for hypertrophic cardiomyopathy
Asymptomatic (major of cases)
Arrhythmia
Dyspnoea i.e. SoB – typically on exertion
Chest pain or angina – the coronary arteries are usually normal but the microscopic coronary arteries within the myocardium becomes narrow
Palpitations
Presyncope
What is the definitive treatment for hypertrophic cardiomyopathies
There is none
Treatment aims to improve symptoms and prevent complications
Name two complications associated with hypertrophic cardiomyopathy
Arrhythmias – most common AF and ventricular tachycardia
Heart block
Define dilated cardiomyopathies (DCM)
Dilated cardiomyopathy refers to ventricular chamber enlargement and impaired contraction of one or both ventricles
Dilatation leads to progressive systolic dysfunction that manifests as poor myocardial contraction and features of heart failure
What condition does dilated cardiomyopathy most commonly cause
Commonly cause heart failure
What age group is dilated cardiomyopathy most common seen in
Most common between 20-60 years old
Name 4 potential causes of dilated cardiomyopathy
- Idiopathic
- Infection e.g. parvovirus B19, coxsackievirus
- Drugs
- Pregnancy
Name some of the clinical features of dilated cardiomyopathy
Characterised by the development of heart failure
Dyspnoea e.g. SoB
Paroxsymal nocturnal dyspnoea: severe, sudden shortness of breath, usually at nighttime
Palpitations: due to the development of arrhythmias
How is dilated cardiomyopathy diagnosed
Visualisation of the heart by echocardiography (ECHO) causing evidence of dilation
How is dilated cardiomyopathy managed
Use of both:
Prognostic medications e.g. angiotensin receptor antagonists, beta-blockers
And
Medications to improve symptoms e.g. diuretics
Other option is cardiac transplantation - more likely to be considered due to the young age of onset
Define arrhythmogenic cardiomyopathy (AMC)
Defined as a group of disorders characterised by arrhythmia(s) alongside myocardial structural abnormalities
Arrhythmogenic cardiomyopathy used to be called arrhythmogenic right ventricular cardiomyopathy (ARVC)
Why did it change?
The condition can affect either the left and/or right ventricles
Arrhythmogenic cardiomyopathy is an inherited condition caused by a mutation of what gene
desmosomal gene
What happens to the heart in arrhythmogenic cardiomyopathy
The myocardium is replaced with fibrous and/or fatty tissue making the heart walls weak causing abnormal function and predisposition to arrhythmias
Name some of the clinical features of arrhythogenic cardiomyopathy
- Asymptomatic
- Palpitations
- Presyncope
- Chest pain
- Breathlessness
- Features of heart failure
How is arrhythmogenic cardiomyopathy diagnosed
- May be challenging
- Combination of typical ECG findings, echocardiography with/without cardiac MRI
How is the aim of arrhythmogenic cardiomyopathy management
The aim is to prevent sudden cardiac death
Usually requires anti-arrhythmias (e.g. beta-blockers) with or without the use of an implantable cardiac defibrillator
What is a pacemaker
Device usually fitted clavicle to only help your heart’s rhythm when it doesn’t beat like it should.
What is an Implantable Cardioverter Defibrillator (ICD)
Device fitted under chest’s skin which continuously monitor your heart’s rhythm and treat dangerous, abnormal rhythms
What is cardioversion
Procedure that sets the heart rhythm back to a normal pattern by sending a strong, electrical impulse to your heart muscle
What is catheter ablation
Procedure that sets the heart rhythm back to a normal pattern by blocking your heart’s electrical paths that aren’t working properly
Name three potential complications of arrhythogenic cardiomyopathy
Heart block – block in the electrical activity of the heart
Heart failure
Sudden cardiac death
The heart is made up of three layers.
Name these layers
Endocardium
Myocardium
Pericardium
The pericardium is a thin, double layer that forms a protective sac around the outside of the heart. It contains a small amount of fluid
What is that fluid called and why is it important
Pericardial fluid
Acts as a lubricant when the heart is contracting.
