The prognostic significance of typical perfusion defects on vasodilator stress myocardial perfusion SPECT in patients with left bundle branch block or right ventricular apical pacing.

Purpose: Left bundle branch block (LBBB) and ventricular pacing may induce typical artefacts that appear as perfusion defects in myocardial perfusion single photon emission computed tomography (MPS). We assessed the prognosis of patients with LBBB or right ventricular apical (RVA) pacing who had chest pain and an MPS with only abnormal activation-related defects (AARD).

Methods: All patients with LBBB or ventricular pacing referred for vasodilator stress MPS between April 2002 and January 2006 were analyzed.