title: Tilt-table testing of patients with pacemaker and recurrent syncope.
abstract: The diagnosis of recurrent syncope in patients with pacemakers (PM) is quite challenging and the etiology of syncope is often multifactorial. To portray the mechanism of syncope in PM patients, we report the results of head-up tilt table testing (HUT) in a series of patients with PM, originally implanted for reasons other than neurally mediated syncope, referred due to syncope or pre-syncope (aborted syncope, vertigo, suspected orthostatic hypotension). Forty-one patients with PM undergoing a HUT in our syncope unit between January 1st, 2007 and December 31st 2011 were included. A standard HUT protocol with nitroglycerine provocation was used and the test results were classified according to current guidelines. Baseline data were retrieved from the medical records. Overall, 54% of patients had a positive response to HUT. Vasodepressor or orthostatic hypotensive response were the most prevalent responses accounting for 72% of patients with a positive test. There were no differences between groups with positive or negative test result regarding age, gender, resting blood pressure and heart rate, daily fluid intake, pacing mode, pacing indication or pacing rhythm at rest. HUT in patients with pacemakers has a high diagnostic yield. Although, the majority of patients had a vasodepressor or orthostatic hypotensive response, cardioinhibitory response leading to syncope was also seen.
authors.affiliation: Department of Clinical Physiology and Nuclear Medicine, Herlev Hospital, Herlev Ringvej 75, 2730 Herlev, Denmark; Department of Clinical Physiology and Nuclear Medicine, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Denmark; Laboratory of Experimental Cardiology, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark.
authors.forename: Christian
authors.initials: C
authors.lastname: Haarmark
authors.affiliation: Laboratory of Experimental Cardiology, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark; Department of Cardiology, Herlev Hospital, Herlev Ringvej 75, 2730 Herlev, Denmark.
authors.forename: Jørgen K
authors.initials: JK
authors.lastname: Kanters
authors.affiliation: Department of Clinical Physiology and Nuclear Medicine, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Denmark; Coordinating Research Centre, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Denmark.
authors.forename: Jesper
authors.initials: J
authors.lastname: Mehlsen
keywords: Cardiac pacing; Nitroglycerine; Pacemaker; Reflex syncope; Syncope; Tilt table test