SYMPOSIUM: Sudden cardiac death Flashcards
What is the definition of sudden cardiac death?
The unexpected death with acute onset in a person with known or unknown cardiac disease
What causes inverted spikes on an ECG?
When the electrode is on the opposite side to the direction of electrical flow through the heart
What mechanism stops ectopic beats in the heart?
A refractory period
What is it called when ectopic beats crush into each other and cause chaos?
Ventricular fibrillation
What is the most common cause of sudden cardiac death?
Ischaemic heart disease
How does scar tissue enable ectopic beats?
It provides many features for re-entry of currents
What causes hypertrophic cardiomyopathy?
An autosomal dominant mutation of cardiac muscle sarcomere genes. Its the most common of sudden cardiac death in young athletes
What is asymmetrical septal hypertrophy?
Thickening of the septum. Can become obstructive
What is systolic anterior motion of the mitral valve?
An increase in ventricular contractile force, due to hypertrophy, pulls the mitral valve out of position when the heart contracts so the whole structure moves forward to meet the septum
When is syncope normal and when is it worrying when it comes to heart disease?
Syncope after exercise is normal because it’s due to a drop in blood pressure. When syncope occurs during exercise, it’s worrying
What causes greater spikes on an ECG?
Greater contractile force
What is arrhythmogenic right ventricular cardiomyopathy?
A multi-genetic disease that causes replacement of right ventricular myocardium with fibro-fatty tissue which interrupts the normal conduction within the heart
What is an epsilon wave on an ECG?
It shows as a dip in the T wave and indicates arrhythmogenic right ventricular cardiomyopathy
What is primary arrhythmia characterised by?
Structurally normal heart and no ischaemia. It includes syndromes like Long QT, wolff-parkinson-white, Brugada
How does Long QT syndrome present on an ECG?
When the T wave is far away from the QRS but everything else is regular
How does Atrial fibrillation present on an ECG?
Missing/unidentifiable P waves. Its irregularly irregular
What is Wolff-Parkinson-White and how does it present on an ECG?
There’s an extra electrical connection between the atria and ventricle in the heart. It presents as a dip in beginning of a QRS segment (a delta wave)
What is Brugada syndrome and how does it present on an ECG?
A genetic disorder affecting fat-type Na+ channel causing an irregular heartbeat. It shows up as a negative T wave on an ECG
What is QTc and what is it used for?
It’s a corrected QT interval used because patients have different heart beats so this allows us to compare to see if the QT is prolonged
Where is a trans venous ICD placed
Under the skin between the muscles and subcutaneous tissue on the left side of the chest. Uses the venous system to access the heart
What does ICD stand for?
Implantable cardiovascular defibrillator
How does an ICD work to stop arrhythmia?
It produces a huge amount of electricity to pass through the left ventricle to stun the heart and produce a refractory period
What is the difference between and S-ICD and a transvenous ICD?
S-ICD doesn’t go into the chest cavity. It works in a similar way to the sticky pads used in emergencies
Which vein is used with a tranvenous ICD?
The left subclavian which connects to the superior vena cava
