Case 5:
A 44 year old man with previously normal ventricular function and a high burden of symptomatic premature ventricular contractions (PVCs) from various RV sites despite multiple previous ablations presented for repeat ablation. He was found to have a small area of endocardial low-voltage (<1.5 mV) at the anterior RV outflow region. PES from the RV apex and basal septum with up to 4 extrastimuli following a drive cycle length of 350ms did not induce any ventricular arrhythmia in the baseline state or following isoproterenol and epinephrine infusions. However, PES from the inferior RV free wall readily induced sustained monomorphic VT. Subsequent cardiac MRI and FDG PET were consistent with sarcoidosis. The details of his clinical course have been previously reported.12