Arrhythmogenic Right Ventricular Dysplasia

Report:

Ventricular tachycardia 162/min

Comment:

The patient had dilated right atrium and ventricle, with normal, mildly hypertrophied left ventricle. The coronary arteries were also normal. In Casualty, adenosine 6 + 12 mg, verapamil 2.5 mg, then sotalol, 60 mg were used; the VT became “pulseless” and DC countershock was required in a hurry.

This is a right ventricular VT in that it has a basic LBBB configuration, provided there is no coronary artery disease37. The tachycardia is easily distinguishable from LBBB aberrancy due to the slow S wave descent in lead V1. The left axis deviation is of no diagnostic value against aberrancy, but tends to differentiate ARVD VT from the RV outflow tract VT: the axis in the latter is right or normal. Left axis deviation is common in ARVD VT38.

Post-cardioversion ECG (Fig 39a) shows 1o AV block, LAHB and non-specific ST/T changes. The single VEB present is of the same morphology as the VT; it has a fully compensatory pause. This may be used to diagnose the VT, retrospectively. Nothing in the trace, however, is particularly suggestive of ARVD: no epsilon waves, no prolongation of V1 complex compared to V6, no anteroseptal T wave inversion.. Insofar as I know, this patient has only one major (selective RV cardiomyopathy) and one minor (VT of appropriate morphology) criterion for ARVD39.

The patient was later paced for AVB induced by anti-arrhythmic drugs (Fig 39b).