The Diagnostic Value of the Treadmill Exercise Test Combined with the
Head Up Tilt Test for Diagnosing Vasovagal Syncope
Abstract
Objective: Increased adrenergic tone can be a trigger of orthostatic
stress of vasovagal syncope (VVS). This study aimed to explore the
diagnostic value of treadmill exercise test (TET) combined with head up
tilt test (HUTT) for VVS. Methods: A total of 73 patients with
unexplained syncope or presyncope were enrolled. VVS was diagnosed in 57
patients according to the Calgary Score (≥-2). Initially, all patients
were subjected to the first HUTT. Then, patients with negative response
in HUTT would further received TET on the next day. At last, patients
who remained getting negative response in TET would be subjected to the
second HUTT within 10min after TET. The symptoms of syncope, heart rate
and blood pressure were recorded during the tests. Results: Syncope or
presyncope occurred in 34 patients in the first HUTT. The sensitivity
and specificity of HUTT for Calgary score-based VVS were 56.1% and
87.5%, respectively. Then, another 14 patients in TET and 9 patients in
the second HUTT experienced syncope or presyncope during the tests. The
sensitivity of TET combined with HUTT for VVS significantly increased to
94.7%, with the specificity only slightly decreasing to 81.3%. No
patients required anticholinergics injection to restore vital signs
during the tests. Conclusion: The combination of TET with HUTT is an
effective and safe diagnostic strategy for VVS.