VEBs After SVEBs

Report:

Sinus tachycardia 112/min

SVEBs

VEBs

Early transition

Nonspecific ST/T changes

Comment:

The second and third VEB follow obvious SVEBs; the predecessor of the first one remains unseen. However, in this patient, all the VEBs seen in several ECGs only occurred after SVEBs. Not all the SVEBs, however, “cause” VEBs. The SVEBs are, judging from their P’ waves, of atrial origin.

This is uncommon, but by no means rare. Presumably the sudden shortening of the cycle length, engendered by the SVEBs, propitiates reentry causing the VEBs. Thus, sometimes you really cannot tell a pacemaker by the company she keeps! Marriott right, as always.

Could the VEBs be SVEBs conducted with RBBB aberration? Most unlikely: there’s the monophasic R with taller left ear in V1; further, the second VEB is superimposed on dissociated sinus P wave.

Below is another example, from a separate admission, 6 weeks later (Fig 138a).

138a. Frequent SVEBs, only one followed by a VEB. There is now a definite LAA, perhaps transiently present after an atrial arrhythmia like AF or MAT. 139. Two neighbours in CCU with incomparable rabbit ears.