Comparison of the active standing test and head-up tilt test for diagnosis of syncope in childhood and adolescence

Abstract

We examined 51 children and adolescents with orthostatic symptoms using two orthostatic tests, the active standing test (the AS test) and head-up tilt test (HUT), and compared circulatory responses, autonomic function in addition to the induction rate of syncope during short-time orthostasis. Syncope was induced in eight patients with both tests, in only six patients with the AS test and in only one patient with HUT. The induction rate was significantly higher with the AS test (p<0.0001). In addition, the AS test is common and daily postural motion and does not require a tilt table. We calculated percent changes in systolic blood pressure at the initial drop (DeltaID-SBP), in systolic blood pressure (DeltaSBP), in diastolic blood pressure (DeltaDBP), in heart rate (DeltaHR), component coefficient variation LF/HF (DeltaLF/HF) from supine to upright. DeltaHR were significantly larger in fainters than in non-fainters with both tests, although there was no difference in DeltaSBP and in DeltaDBP. In six fainters only with the AS test, DeltaHR was significantly larger with the AS test than with HUT. With the AS test DeltaID-SBP were correlative with DeltaLF/HF, and DeltaLF/HF were correlative with DeltaHR, whereas these relations were not clear in HUT. These results indicated the AS test caused cardiac sympathetic activation associated with an initial pressure drop, and was more prone to induce syncope with a greater HR increase in some patients. We conclude the AS test is as potential as HUT as a diagnostic test for syncope.

Effects of variation in posture and respiration on RSA and pre‐ejection period

“…Changes from supine to sitting to standing postures led to a shortening of interbeat interval and a decrease in RSA, reflecting the expected decrease in cardiac vagal activity that has been well documented in studies using either passive head-up tilting or active standing (Cooke et al, 1999;Furlan et al, 2000;Matsushima, Tanaka, & Tamai, 2004;Mukai & Hayano, 1995;Siebert, Drabik, Lango, & Szyndler, 2004).…”

Delayed orthostatic hypotension

“…A recent report examining the diagnostic discrimination of tilt-table testing and active standing in patients with neurally mediated syncope drew a similar conclusion in a younger population group. 11 The symptomatic and asymptomatic patients in the present study demonstrated no difference in severity or time of BP falls on tilt test. The relationship between symptoms and the magnitude of the BP fall in patients with orthostatic intolerance is not linear; some patients with autonomic failure with profound BP falls immediately after standing due to autonomic failure are asymptomatic while patients with postural tachycardia syndrome and minimal BP falls report severe symptoms of orthostatic intolerance.…”

Cardiovascular response to functional electrical stimulation and dynamic tilt table therapy to improve orthostatic tolerance

“…This is possible, since brief static contractions in the leg muscles during upright stance will trigger the exercise and baroreceptor reflexes (Borst et al, 1982), thus resulting in an immediate increase in heart rate and thereby affecting blood flow. Furthermore, quiet standing was found to have a greater tendency to induce syncope when compared to HUT (Matsushima et al, 2004), which suggests that autonomic function and cardiovascular response differ between tilt and standing situations. Compared to isometric FES, passive mobilization and dynamic FES were able to either maintain or increase the mean IVC CSA , suggesting that these modalities are more effective for maintaining or improving circulatory hemodynamics under orthostatic conditions.…”