Cardiac Myopathies & Channelopathies Flashcards

1
Q

What is a cardiomyopathy?

A

A problem with heart muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What types of congenital heart defects are there?

A

Structural

Cardiomyopathies

Channelopathies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

All cardiomyopathies will present themselves within the first few years of life. True or false?

A

False!

They can start to develop at any age.
Some people have no abnormalities for many years and suddenly one starts to manifest itself

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Who do we screen for congenital heart defects?

A

People who have affected first degree relatives

Groups at risk of mortality: athletes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

List some cardiomyopathies.

A

Hypertrophic
Dilated
L ventricle non-compaction
Arrhythmogenic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe some other non heart specific conditions that can cause CVS diseases.

A

Palmoplantar keratoderma

Marfan’s syndrome:
Can cause an aortic root aneurysm

Familial Hypercholestrolaemia:
Can’t take up cholesterol from blood due to an LDL receptor fault. Excess blood cholesterol = heart problems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

List some Channelopathies.

A

Long QT
Short QT
Brugada
CPVT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the features of hypertrophic cardiomyopathy?

A

Thick walls, small cavities

When they contract the atria & ventricles contract down to almost nothing

Disorganised arrangement of myocytes

Fibrotic tissue develops: arrhythmias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why does fibrotic tissue cause arrhythmias?

A

Fibrotic tissue is an electrical insulator, so it blocks electrical conduction in the heart.

Causes random bursts of ventricular arrhythmias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How do patients with hypertrophic cardiomyopathy present?

A
Sudden death
Angina
Dyspnoea
Palpitations
Syncope
Jerky pulse
Harsh ejection systolic murmur
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What tests can you do to confirm hypertrophic cardiomyopathy?

A

ECG: shows up the random bursts of ventricular arrhythmia

Echo: shows up the hypertrophic walls

Exercise test with heart monitor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the treatment of hypertrophic cardiomyopathy?

A

Beta blockers or verapamil (a Ca antagonist): to reduce ventricular contractility

Amiodarone: anti-arrhythmic drug

Anti-coagulants: to prevent a clot forming as a result of arrhythmia

Septal myomectomy

Implantable defribrillator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is septal myomectomy? How is it done?

A

Removal of a portion of the septum that is obstructing the flow of the blood from the ventricle to the aorta

Can be done surgically or chemically (alcohol ablation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is an implantable defibrillator?

A

A device placed in the heart that senses and corrects any arrhythmias that occur

It corrects them by giving electric shocks to get the heart back into a normal rhythm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which type of cardiomyopathy causes the most sudden deaths?

A

Hypertrophic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the features of dilated cardiomyopathy?

A

A dilated, flabby heart
Thin walls
Chambers don’t contract properly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How do patients with dilated cardiomyopathy present?

A

They present very young with heart failure

Breathless
Fatigue
Fluid retention
Emboli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the clinical signs of dilated cardiomyopathy?

A
Raised pulse
Low BP
Raised JVP
S3 gallop
Mitral or tricuspid regurgitation
Pleural effusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What tests can you do to confirm dilated cardiomyopathy?

A

Bloods:
Look for B-natriuretic peptide which will be raised
U&E: low Ca2+

CXR: cardiomegaly, pulmonary oedema

ECG: tachycardia

Echo: flabby, dilated heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the significance of low Ca2+ in dilated cardiomyopathy?

A

Low Ca2+ indicates a poor prognosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the treatment of dilated cardiomyopathy?

A

Bed rest

Diuretics

Digoxin: cardiac stimulant

ACE inhibitors

Anti-coagulants

Transplant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the features of left ventricle non-compaction?

A

The inside of the heart is sponge like during development and is compacted prior to birth to leave chambers

In this condition there’s a fault in the compaction process and the inside of the heart, especially the L ventricle remains spongy and there are excessively prominent trabeculations

This causes poor pumping performance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How do patients with left ventricle non-compaction present?

A
Heart failure symptoms
SOB
Oedema
Fatigue
Exercise intolerance

Tachycardia
Blood clot formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How is left ventricle non-compaction diagnosed?

A

When the trabeculations are more than twice as thick as the underlying ventricular wall

25
What tests can you do to confirm left ventricle non-compaction?
``` Echo CT PET MRI to look at the trabeculations ```
26
What is the treatment of left ventricle non-compaction?
ACE inhibitors B-blockers Aspirin Implantable pacemaker Heart valve replacement Heart transplant
27
What is palmoplantar keratoderma?
A syndrome causing abnormal thickening of palms and soles when there is minor trauma It also causes cardiomyopathy: fibro-fatty replacement of the right ventricle Fibro-fatty tissue causes arrhythmias
28
What is a channelopathy?
Disturbed function of ion channels or the proteins that regulate them Cardiac Channelopathies appear normal on a scan but abnormal on ECG
29
What are the features of long QT?
There are a few different forms Q - T segment is longer than it should be You get random bursts of ventricular arrhythmias
30
What can cause a cardiac arrest in patients with Long QT?
Stress Sudden noise Strenuous exercise Slow HR during sleep Drugs: a huge list of drugs that can trigger a cardiac arrest
31
What is the pathophysiology of Long QT?
Flow of ions in and out of cardiac myocytes generates the heart's electrical activity In Long QT flow of potassium ions out of cardiac myocytes is delayed This means that after each heartbeat the heart takes longer to repolarise (reset itself)
32
What are the causes of Long QT?
Inherited Drug induced Anorexia: due to dangerous electrolyte imbalances
33
Which gender is more commonly affected by Long QT?
Females
34
What are the symptoms of Long QT syndrome?
Sudden death Asymptomatic Blackouts Seizures Arrhythmia: torsade de pointes Ventricular fibrillation
35
What is torsade de pointes arrhythmia?
A type of arrhythmia that can lead to sudden cardiac arrest It is a ventricular tachycardia
36
What is ventricular fibrillation? | Why is it so dangerous?
Uncoordinated contraction of the cardiac muscle of the ventricles The heart quivers rather than contracts This means that the heart can't pump blood around the body properly as there's no contraction occuring
37
What is the treatment for Long QT?
Drugs: B-blockers Implantable cardioverter-defibrillator (ICD) that can detect and correct arrhythmias Avoid trigger: strenuous exercise, loud noises
38
Investigations of Long QT?
ECG History: syncope, blackouts etc. Family history of Long QT, sudden death
39
What are the features of short QT?
QT segment is shorter than it should be Abnormal heart beat V-fib
40
What are the symptoms of short QT?
Palpitations Unexplained syncope V-fib Sudden death
41
What is the pathophysiology of short QT?
Increased activity of K channels in cardiac myocytes, so K ions flow out of the cells quicker than they should This alters the electrical activity of the heart
42
What causes short QT?
Inherited genetic mutations
43
What is the treatment for short QT?
Implantable cardioverter-defibrillator (ICD) Detects and corrects arrhythmias Anti-arrhythmic agents: quinidine
44
Investigations of Short QT?
ECG History of blackouts etc. Family history
45
What are the features of Brugada Syndrome?
Arrhythmias caused by problems with the electrical activity of the heart
46
What are the symptoms of Brugada Syndrome?
``` Blackouts Seizures Heart palpitations V or A-fib Sudden death ```
47
Which type of people are mot affected by Brugada Syndrome?
Males Young and middle age Japanese & SE Asian descent
48
What is the pathophysiology of Brugada Syndrome?
Genetic mutations that cause problems with ion channels in the heart, which causes problems with heart contraction There are a few mutations that cause Brugada, one of which reduces the flow of sodium ions into the cell
49
Investigations of Brugada.
ECG: does not always show up problems, need to give a drug that will help to show up the problem Genetic testing
50
What drug can be used to show up problems on an ECG when diagnosing Brugada? How does it work?
Ajmaline: an anti-arrhythmic It blocks sodium channels It will show up any abnormalities of heart electrical activity on an ECG
51
How do you treat Brugada?
ICD pacemaker No drugs available Avoid triggers: fever, diarrhoea, many more
52
What does ICD pacemaker stand for?
Implantable cadioverter defibrillator
53
What does CPVT stand for?
Catecholaminergic polymorphic ventricular tachycardia
54
What are the features of CPVT?
Ventricular tachycardia that arises during times when they have high adrenaline levels (catecholaminergic) Can cause fainting or sudden death
55
What are the symptoms of CPVT?
Associated with exercise, emotion, things associated with high adrenaline levels Syncope Blackouts Seizures - if V tachycardia persists If it persists further, V-fib can develop Sudden death
56
Investigations for CPVT.
ECG is not helpful on its own Stress test: stress the heart using exercise or catecholamines This will show up premature ventricular contractions which can sometimes progress into ventricular tachycardia
57
What is polymorphic ventricular tachycardia?
A form of ventricular tachycardia where there are QRS complexes varying in amplitude, axis and direction
58
With the Channelopathies, how come sometimes only syncope occurs and other times death occurs?
When the heart goes into ventricular tachycardia, sometimes it corrects itself and the heart goes back to normal sinus rhythm Sometimes it doesn't and the heart goes into V-fib and can't usually get out of this without medical intervention This is when death occurs