Comparison of short head-up tilt test with conventional protocol after omission of nonmedicated phase in children and young adults

Background: Syncope is an important and common clinical condition, and the neurally mediated syncope is the most frequent type of syncope. Tilt testing is considered as a first-line diagnostic test. Materials and Methods: We conducted the conventional and modified tilt test on 200 subjects in the age range of 5-20 years. In conventional protocol, the patient was tilted for up to 15 min without medication. If syncope did not develop, the patient received 0.1 mg/kg sublingual isosorbide dinitrate. Then, the patient was continued to be tilted for another 15 min. In modified tilt test, before starting the test, the patient received 0.1 mg/kg isosorbide dinitrate sublingually in supine position. Then, the table was tilted for a maximum of 25 min or until the test became positive. Results: In conventional tilt test group 79.13% and in modified tilt test group 87.06% of subjects showed positive results. In conventional tilt test, the mean of response time was 17.67 ± 4.74 min. The mean of the total time of conventional tilt test was 49.81 ± 5.57 min. In modified tilt test, the mean of response time was 7.24 ± 4.83 min. The mean of the total time of modified tilt test was 35.09 ± 7.58 min. Furthermore, the means of both response and total times between two groups were significantly different ( P < 0.001). Conclusions: Our study showed that we can save about 15-20 min in total test time which may increase the cooperation and compliance of young patients and decrease their anxiety with this new protocol.