Tilt table testing in patients referred from an epilepsy clinic

OBJECTIVE To assess the role of head up tilt testing (HUT) in diagnosing probable or possible vasovagal syncope (VVS) in patients referred from an epilepsy clinic. METHODS One hundred thirty two patients underwent HUT over 36 months. Complete data were available on 128 patients (52 male) aged 14-80 (mean 36.7) years. The main indication for HUT (head up tilt at 70 degrees for 45 minutes) was recurrent undiagnosed blackouts, likely to be VVS. Patients were divided, prior to knowledge of the HUT results, into probable VVS, possible VVS, or probable/possible VVS associated with definite epilepsy. RESULTS HUT was positive in 72 patients (56%), and led to an alternative definite diagnosis in 31 (24%). Diagnostic change was more likely in those provisionally labelled either as possible VVS (15 of 34; 44%) or as a combination of epilepsy with possible or probable VVS (12 of 19; 63%) compared to those with probable VVS (4 of 75; 5%; P<0.01).Of the 45 patients previously treated with antiepileptic medications 27 did not have epilepsy. CONCLUSION HUT has an important role in confirming or refuting the diagnosis of VVS in patients presenting with undiagnosed blackouts to an epilepsy clinic, and particularly so in patients with possible rather than probable VVS, and in those thought to have a combination of epilepsy and possible or probable VVS.