Wolff Parkinson White Syndrome

Wolff Parkinson White syndrome is an unusual heart rhythm condition in which patients can develop sudden onset of fast heart palpitations. These can be associated with light-headedness/dizziness, blackouts, chest pain and in very rare cases, sudden death. However the good news is that this is a completely curable condition.

In this video, I will try and hopefully give you some insight into this interesting condition.

Wolff –Parkinson-White syndrome was first described by 3 physicians – Louise Wolff, Sir John Parkinson and Paul Dudley White who described 11 patients who had and abnormal resting ECG and who developed intermittent sudden episodes of fast heart rate. There were 3 main ECG abnormalities seen.

Firstly: the PR interval was short
Secondly: the QRS was abnormally wide
Thirdly: they had something called a Delta wave which was an unusually slurred upstroke to the QRS segment.

The fundamental problem in patients with this condition is that they have an extra electrical pathway in their heart.

In the normal heart, the top chambers of the heart (the atria) and the bottom chambers of the heart (the ventricles) are electrically isolated. So normally what happens is that an impulse is generated in the sino-atrial node (the pacemaker of our heart that god gives us when we are born). The impulse can only travel to the ventricle via an electrical pathway known as the His-Purkinje system. To get to the His Purkinje system, the impulse has to go through the AV node which can be likened to a toll booth and the AV node ensures that the impulses don’t go through too quickly. Once the impulse gets to the ventricles, it causes the ventricles to contract. Patients with WPW however have another electrical pathway too and usually as there is no AV node, these pathways conduct electricity much quicker that the normal. These extra pathways are called accessory pathways and the problem is that they can therefore provide a short-circuting mechanism by which an impulse could go either down the AV node and then back up through the accessory pathway or down the accessory pathway and up through the his-purkinje system thereby causing a very rapid heart rate which can then be manifest in the patient as a sudden onset of very fast palpitations