Diagnostic utility of the head-up tilt test in syncope and the related complications

Abstract

Background: Recurrent syncope is a distressing symptom in which the cause may remain undetermined. A definitive diagnosis may help the patients to lead a normal life and avoid the unnecessary risk to their lives. Objective: To evaluate the effectiveness and safety of Head up Tilt Test (HUTT) in patients with undiagnosed syncope and to detect and follow up any complications arising out of the procedure. Material and methods: The head up tilt table test was performed in department of cardiology. 72 patients with a history of syncope or presyncope underwent upright tilt table testing to exclude vasovagal syncope, with baseline tilt and if negative followed by progressively increasing doses of isoprenaline infusion. 70° tilt was used and continuous heart rate and non-invasive BP recordings were made every 2 minutes or earlier when symptomatic. Results: The mean age of the patients was 48±16 years. None of the patients had carotid sinus hypersensitivity. Forty-five patients (62.5%) were positive for syncope. Four (5.55 %) were positive during the baseline tilt and forty-one (56.9%) were positive with the use of isoprenaline during tilt. The majority of positive responses were mixed 23 (51.11%), 17(37.77%) were vasodepressor and 5(11.11%) were cardioinhibitory. The mean time to syncope was 31.84 ± 8.0 minutes. There was a mean drop of 55.65 mmHg in systolic blood pressure and 36.06 mmHg in diastolic blood pressure in the positive group (p = <0.001 for both).No statistical significance was observed as regards the age ,sex and type of response. No significant untoward incidents were noted except partial seizures in one patient. Conclusion:The head-up tilt test is a simple, non-invasive, relatively safe test which is useful in documenting objective measures of orthostatic hypotension that cannot be obtained in a clinical setting.