VT versus SVT with aberrancyEKG Criteria

Features favoring VT Features favoring SVT w/aberrancyAV dissociation Consistent onset of tachycardia with PACsFusion/Dressler (capture) beats Short RP interval (<0.1 sec)2:1 ventriculoatrial block 1:1 ventriculoatrial relationshipSlightly irregular R-R intervals Regular R-R intervalsAbsence of RS complex in the precordial leads Triphasic pattern in V1QRS concordance in the precordial leads similar to normallyconducted beats Initial vector of abnormal QRS complexPredominantly negative QRS complexes in V4 - V6QR complexes present in V2 - V6R-S width > 100ms in at least one precordial leadQRS duration > 140msExtreme left superior axis deviationNet area under QRS negative in leads I and II

MORPHOLOGY CRITERIA

Features favoring VT Features favoring SVT w/aberrancyRBBB pattern: RBBB pattern:

Monophasic R or biphasic qR, QR, or RS in V1 Triphasic rSR' in V1

S > R or QS in V6 Triphasic rSR' in V6

R > S in V6

LBBB pattern: LBBB pattern:Broad R wave or wide R-S length (> 30msec) in V1 orV2

No R in V1

Notched downstroke of S-wave in V1 or V2 Small narrow R in V2

> 60msec to nadir of S in V1 or V2 No slurring of S-wave downstroke

qR or QS pattern in V6 Monophasic R in V6

Presence of septal Q in I & V6

BRUGADA Criteria for VT

References

Wellens, et al. The value of the electrocardiogram in the differential diagnosis of a tachycardia with a widened QRScomplex. Am J Med 1977; 64: 27-33. Brugada, et al. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex.Circulation 1991; 83: 1649-59.

D. Suh 12/13/00