Tachycardia Flashcards
Broad complex tachycardia is assumed to be ventricular in origin but what else can it be?
Supraventricular rhythm with aberrant conduction e.g. atrial fibrillation with RBBB
If patient with any tachycardia has adverse signs signs, what treatment is indicated?
Cardioversion (synchronized DC shock)
History of alcohol abuse + torsades de point on ECG- likely diagnosis?
Hypokalaemia
Syndrome caused by a congenital accessory conducting pathway between the atria and ventricles, leading to AV re-entry tachycardia
Wolff-Parkinson White syndrome
ECG features of WPW? (2)
Short PR interval
Wide QRS with slurred upstroke (delta wave)
Which pattern of axis deviation is normally associated with WPW?
Usually LAD
Definitive treatment for WPW?
Radiofrequency ablation of the accessory pathway
Sudden onset of a narrow complex tachycardia, typically an atrioventricular nodal re-entry tachycardia
Supraventricular tachycardia
Acute management of SVT? (3)
Vagal manouevres e.g. Valsalva
Intravenous adenosine
Electrical cardioversion
IV adenosine is contraindicated in…
What alternative should be used?
Asthma
Verapamil
Dosage of adenosine in SVT?
6mg, then 12mg, then 12mg
Management of regular, broad complex tachycardia?
a) adverse signs
b) no adverse signs
a) cardioversion
b) Loading dose of amiodarone followed by 24 hour infusion
Broad complex tachycardia with an irregular rhythm is either…
AF with BBB- treat as for narrow complex
Polymorphic VT (e.g. Torsades de point)
Treatment of Polymorphic VT
IV magnesium
Broad-complex tachycardia originating from a ventricular ectopic focus?
Ventricular tachycardia
Why does ventricular tachycardia need to be managed immediately?
Potential to precipitate ventricular fibrillation
Two main types of ventricular tachycardia?
Monomorphic VT- usually caused by MI
Polymorphic VT
What is torsades de point and what is it usually precipitated by?
Type of polymorphic VT; QT prolongation
Inherited condition associated with delayed repolarization of the ventricles?
Long QT syndrome
Why is long QT syndrome important to recognise?
May lead to ventricular tachycardia and collapse/sudden death
Management of long QT (4)
Avoid drugs which prolong QT
Avoid other precipitants
Beta blockers
ICD
Most important metabolic cause of ventricular tachycardia?
Hypokalaemia
Medical therapy for WPW syndrome? (3)
Sotalol
Amiodarone
Flecainide
Digoxin overdose usually causes what heart arrythmia?
Ventricular tachyardia
How is digoxin overdose managed?
Digibind (digoxin antidote)
History: syncopal episodes
ECG: biphasic T waves, saddle-shaped ST segments
Brugada syndrome
Treatment of Brugada syndrome?
ICD