Wolff-Parkinson-White Syndrome

Question 1

Define Wolff-Parkinson-White syndrome.

Answer 1

Wolff-Parkinson-White occurs when one or more strands of myocardial fibres capable of conducting electrical impulses (known as accessory pathways or bypass tracts) connect the atrium to the ipsilateral ventricle across the mitral or tricuspid annulus.

Question 2

Explain the aetiology/risk factors of Wolff-Parkinson-White syndrome.

Answer 2

Ebstein’s anomaly
Hypertrophic cardiomyopathy
Mitral valve prolapse
Atrial septal defect
Ventricular septal defect
Transposition of great vessels
Coarctation of aorta
Dextrocardia
Coronary sinus diverticula
Right and left atrial aneurysms
Cardiac rhabdomyomas
Marfan’s syndrome
Friedreich’s ataxia
Family history

Question 3

Summarise the epidemiology of Wolff-Parkinson-White syndrome.

Answer 3

The prevalence of WPW-pattern ECG in the general population is 0.1% to 0.3%. The yearly incidence is 0.004% to 0.1% (50% of these are asymptomatic).

Question 4

Recognise the presenting symptoms of Wolff-Parkinson-White syndrome. Recognise the signs of Wolff-Parkinson-White syndrome on physical examination.

Answer 4

Palpitations
Dizziness
Shortness of breath
Chest pain
Atrial fibrillation
Atrial flutter
Congenital cardiac abnormalities

Question 5

Identify appropriate investigations for Wolff-Parkinson-White syndrome and interpret the results.

Answer 5

ECG: Slurred PQ (delta waves)
Echocardiogram
Treadmill exercise test
Electrophysiology study