A young patient comes into your RESUS area complaining of palpitations, and you get handed this EKG. What do you do?

A fib with an accessory pathway can go so fast that it can be misdiagnosed as V tach/ SVT, however if misdiagnosed, the usual treatment could cause you to push the patient into v fib and even death!

Can reach rates of 250-300 as opposed to our usual bread and butter a fib with RVR

Avoid all AV nodal blockers if concerned that there may be an accessory pathway involved


Procainamide is your agent of choice

A great review of the pre-excitation syndromes


EKG Guru Amal Mattu has a wonderful 20 min video on this topic that explains it really well