title: Orthodromic pacemaker circus movement tachycardia.
abstract: We report on the case of a 33-year-old woman with sick sinus syndrome who had an orthodromic pacemaker circus movement tachycardia (PCMT), with antegrade atrioventricular (AV) conduction and a retrograde pathway by means of a DDD (AV universal) pacemaker. This PCMT was provoked and sustained by premature ventricular contraction-synchronous atrial stimulation (PVC-SAS), which is a new feature for the prevention of antidromic PCMTs. The conditions for occurrence of this tachycardia were: PVC-SAS; atrial undersensing; first degree AV block. Recommendations for prevention of this pacemaker-mediated tachycardia are given.
mesh_terms: D000328:Adult; D005260:Female; D006327:Heart Block / Q000628:therapy*; D006801:Humans; D010138:Pacemaker, Artificial / Q000009:adverse effects*; D012804:Sick Sinus Syndrome / Q000628:therapy*; D013610:Tachycardia / Q000209:etiology*