WPW syndrome with atrial fibrillation

A 37 years old male came with the history of acute onset palpitation of two hours duration. Tachycardia ECG is shown below.

Tachycardia ECG (Click on the image to enlarge it)

ECG is showing broad QRS complex tachycardia, irregularly irregular @ 200 beats per minutes, No AV dissociation no fusion beats no capture beats seen, QRS is showing RBBB morphology in lead V1, variable QRS morphology, negative delta wave in lead II,III, avF,  Positive delta wave are seen in lead I, avL, V1 to V4 

ECG Diagnosis: Broad complex tachycardia, irregularly irregular suggestive

Differential diagnosis: Pre-excited tachycardia, Atrial fibrillation with underlying aberrancy.

Another tachycardia ECG of the patient

Another tachycardia ECG of the patient

Patient was given injection amiodarone but his tachycardia did not subside. DC cardioversion was done. Post cardioversion sinus ECG is shown below

Sinus ECG(Click on the image to enlarge it)

ECG is showing sinus rhythm @ 80 bpm, PR  60 msec, Left axis deviation, Negative delta wave seen in lead II, III, avF, Positive delta wave seen in lead V2-V5. Ecg is suggestive of WPW syndrome. As the delta wave is negative in lead 2, it is most likely pathway from coronary sinus diverticulum.
The patient underwent electrophysiological study which showed WPW syndrome with pathway originating from Coronary sinus diverticulum.

Lets discuss pathway localization for WPW syndrome.

Thank you

Praveen Gupta