wolff-parkinson-white syndrome

what is WPW?

pre-excitation syndrome caused by a congenital accessory pathway

what is the main clinical feature of WPW?

episodic tachyarrhythmias

what is the accessory pathway called?

Bundle of Kent

what are the two options of conduction for WPW?

antegrade and retrograde

which out of antegrade and retrograde conduction can be seen on ECG?

antegrade

what are the the signs on ECG?

- short PR interval

- early slurred delta wave in QRS complex

what may be seen in a right-sided accessory pathway?

left axis deviation

what may be seen in a left-sided accessory pathway?

right axis deviation

which is more common out of right or left axis deviation in WPW?

left

what is type A and B WPW?

type A - left sided pathway

type B - right sided pathway

how do you differentiate between type A and B on ECG?

A - dominant R wave in V1

B - no dominant R wave in V1

what is the main complication of WPW?

atrial fibrillation which could then lead to ventricular fibrillation

what conditions are associated with WPW?

- hypertrophic obstructive cardiomyopathy (HOCM)

- mitral valve prolapse

- Ebstein's anomaly

- thyrotoxicosis

- secundum ASD

what is the definitive treatment of WPW?

radiofrequency ablation of accessory pathway

what is the medical management of WPW?

- sotalol

- amiodarone

- flecainide

when should sotalol be avoided?

coexistant AF

why should sotalol be avoided in AF?

prolonging of refractory period at AV node increases rate of transmission through accessory pathway, increasing ventricular rate and potentially deteriorating into ventricular fibrillation