WPW ‘A’ Mime of Inferoposterior Infarction

Report:

Sinus rhythm 68/min

Wolff-Parkinson-White type ‘A’ conduction

Comment:

The QRS appears narrow and the PR interval normal in several – in fact, most – leads. On the other hand, the latter is completely effaced by a δ wave in V2 and V3. There is concordant positive precordial pattern. Best of all, there is a narrow-complex SVT 150/min preceding this trace (Fig 18a), but one is not to know that from the previous page! That may well have been the cause of his chest “tightness”.

The original SVT was much faster, but slowed down to 150/min with sotalol. The drug may have exerted a balanced slowing of both the normal and the accessory pathway, preserving the reentry. By then the patient’s medical records were brought up (revealing WPW syndrome) and procainamide given in view of its known blocking properties of the bundle of Kent. It worked, but it was overegging the pudding a little: any ordinary AV nodal blocker available in 1994 (e.g., verapamil) would have interrupted the SVT. Even digoxin.

Sotalol, like flecainide or procainamide is better used for AF in WPW if immediate defibrillation is not necessary.