title: Wenckebach phenomenon in the exit area from a transvenous pacing electrode.
abstract: An unusual type of exist block from a transvenous pacing electrode was recorded in a 63-year-old man with an acute inferior infarct and cardiogenic shock. The pacemaker artefact to QRS interval increased gradually till there was loss of capture. A gradual change from I:I pacing rhythm to 4:3 and 3:2 Wenckebach cycles was recorded. This was followed by a fixed 2:I pacemaker artefact to QRS block.
mesh_terms: D004562:Electrocardiography; D006327:Heart Block / Q000209:etiology* / Q000503:physiopathology; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial / Q000009:adverse effects*