title: Shocking truths about implantable cardioverter defibrillator monitoring zones.
abstract: A 36 year-old man with hypertrophic cardiomyopathy and an ATLAS + DR implantable cardioverter defibrillator (ICD) (St. Jude Medical, Inc., St. Paul, MN, USA) for primary prevention received a shock while cycling. The ventricular fibrillation detection threshold was 182 beats/min. An additional monitoring zone was programmed to 156 beats/min with all discriminators "on" except morphology. On interrogation, the ICD shock followed sinus tachycardia. In the absence of a monitoring zone, device therapy would not have been expected. We explore the mechanisms by which monitoring zones could potentially contribute to inappropriate ICD therapy and offer trouble-shooting tips.
authors.affiliation: Electrophysiology Service, Montreal Heart Institute, Montreal, Quebec, Canada.
authors.forename: Fadi
authors.initials: F
authors.lastname: Mansour
authors.forename: Bernard
authors.initials: B
authors.lastname: Thibault
authors.forename: Marc
authors.initials: M
authors.lastname: Dubuc
authors.forename: Peter G
authors.initials: PG
authors.lastname: Guerra
authors.forename: Laurent
authors.initials: L
authors.lastname: Macle
authors.forename: Ramon
authors.initials: R
authors.lastname: Brugada
authors.forename: Denis
authors.initials: D
authors.lastname: Roy
authors.forename: Mario
authors.initials: M
authors.lastname: Talajic
authors.forename: Paul
authors.initials: P
authors.lastname: Khairy
mesh_terms: D000328:Adult; D002312:Cardiomyopathy, Hypertrophic / Q000517:prevention & control*; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004554:Electric Countershock / Q000009:adverse effects*; D004868:Equipment Failure; D019544:Equipment Failure Analysis; D006801:Humans; D008297:Male; D017180:Tachycardia, Ventricular / Q000209:etiology* / Q000517:prevention & control*