Arrhythmias Flashcards
What are the two classes of arrhythmias described by where the arrhythmia arises?
Supraventricular
Ventricular
Supraventricular arrhythmias tend to have narrow QRS complexes. True/False?
True
Because the arrhythmia does not originate from ventricles
The AV node is the only point of electrical contact between the atria and ventricles. What may additionally be present to cause pathological conduction?
Fibrous ring
What are ectopic beats?
Beats/rhythms that originate outwith the SA node
Ectopic beats may not be dangerous. True/False?
True
Why might ectopic beats not be harmful?
Depends on where they originate - if in non-contractile areas, they are unlikely to affect cardiac output
Name the main supraventricular arrhythmias
SVTs: atrial fibrillation, atrial flutter, ectopic atrial tachycardia
Bradycardias: sinus bradycardia, sinus pauses
Name the main AV node arrhythmias
AV node reentry Accessory pathway AV block (1st, 2nd, 3rd degree)
Name the main ventricular arrhythmias
Premature ventricular complex
Ventricular tachycardia
Ventricular fibrillation
Asystole
What are the 3 main physiological types of arrhythmia?
Altered automaticity
Triggered activity
Reentry (accessory pathway)
List the investigations you would do for arrythmias
ECG/exercise ECG/24hr ECG CXR Echocardiogram Event recorder EP study (induce arrhythmia to map pathway)
How would acute SVT be managed?
Vagal manoeuvres, carotid massage
IV adenosine
IV verapamil
Give examples of some vagal manoeuvres
Holding your breath and bearing down (Valsalva)
Immersing face in ice-cold water (diving reflex)
Holding nose/unblocking ears
What is the treatment of choice for managing chronic arrhythmias?
Radiofrequency ablation
What is radiofrequency ablation?
Selective cauterisation of cardiac tissue to prevent tachycardia
Target reentry circuit or automatic myocite
Which drugs must be stopped before radiofrequency ablation?
Antiarrhythmic drugs 3-5 days beforehand