Abstracts

Rationale: At the Level 4 Epilepsy center University of Colorado Hospital, approximately 30 percent of inpatient video EEG monitoring stays for characterization of seizure events are non-diagnostic. Besides the financial and social weight of this testing for non diagnostic admissions, there is additional burden on patient and provider of possible misdiagnosis and potential initiation or continuation of unnecessary anti-seizure medications with side effects. Tilt table testing is considered the diagnostic gold standard for evaluation and characterization of loss of consciousness syncopal events. In 2009, The American Academy of Cardiology/ American Heart Association and European Society of Cardiology listed differentiating syncope with jerking movements from epilepsy as an indication for Tilt-Table Testing. Many institutions have incorporated video EEG monitoring with tilt table testing for evaluation of unexplained syncopal spells to better characterize clinical phenomenon recognized with vasodepressor syncope such as convulsive syncope. Added benefit of identification of psychogenic non epileptic seizures has been documented. (LaRoche S et al 2011) Methods: A Retrospective analysis of Tilt table EEG testing performed on 26 consecutive patients from 2013 to 2016 at UCH was reviewed to assess for the percentage of diagnostic tilt table EEGs performed versus non diagnostic. Additionally, events were identified as either Epileptic, Non Epileptic, Vasodepressor syncope, and Postural orthostatic tachycardia syndrome. Clinical history was reviewed for presenting clinical features which prompted Tilt Table EEG testing. EEG was recorded throughout the study with video and EKG single lead tracing. Results: Tilt table EEG testing was diagnostic in 20 of 26 patients (76 %). Syncope was observed in 18 of 26 patients ( 69 %). Diagnoses included Type 1 mixed cardioinhibitory response, Type 2a, Cardioinhibitory response,Type 2b Cardioinhibitory response, Type 3 Pure Vasodepressor response. Postural Orthostatic Tachycardia syndrome was identified in 4 additional patients. Three patients experienced Non Epileptic seizures. Common clinical features in patients experiencing syncope included one or more of the following: a history of symptomatic orthostatic intolerance, hypermobility, and "seizure aura" with characteristics similar to vertebrobasilar dysfunction ( tunnel vision, vertigo, muting of ears). Conclusions: Our review suggests that in select patients, Tilt table testing with video EEG monitoring may provide an initial diagnostic alternative to Epilepsy monitoring unit admissions for characterization of refractory loss of consciousness events. It may also represent a diagnostic strategy for Medical Centers without access to an inpatient video EEG monitoring unit in select patients. Funding: No funding