Efficacy of Servo-Controlled Splanchnic Venous Compression in the Treatment of Orthostatic Hypotension: A Randomized Comparison With Midodrine

Abstract

Splanchnic venous pooling is a major hemodynamic determinant of orthostatic hypotension, but is not specifically targeted by pressor agents, the mainstay of treatment. We developed an automated inflatable abdominal binder that provides sustained servo-controlled venous compression (40 mm Hg) and can be activated only on standing. We tested the efficacy of this device against placebo and compared it to midodrine in 19 autonomic failure patients randomized to receive either placebo, midodrine (2.5-10 mg), or placebo combined with binder on separate days in a single-blind, crossover study. Systolic blood pressure (SBP) was measured seated and standing before and 1-hour post medication; the binder was inflated immediately before standing. Only midodrine increased seated SBP (31±5 versus 9±4 placebo and 7±5 binder, P=0.003), whereas orthostatic tolerance (defined as area under the curve of upright SBP [AUCSBP]) improved similarly with binder and midodrine (AUCSBP, 195±35 and 197±41 versus 19±38 mm Hg×minute for placebo; P=0.003). Orthostatic symptom burden decreased with the binder (from 21.9±3.6 to 16.3±3.1, P=0.032) and midodrine (from 25.6±3.4 to 14.2±3.3, P<0.001), but not with placebo (from 19.6±3.5 to 20.1±3.3, P=0.756). We also compared the combination of midodrine and binder with midodrine alone. The combination produced a greater increase in orthostatic tolerance (AUCSBP, 326±65 versus 140±53 mm Hg×minute for midodrine alone; P=0.028, n=21) and decreased orthostatic symptoms (from 21.8±3.2 to 12.9±2.9, P<0.001). In conclusion, servo-controlled abdominal venous compression with an automated inflatable binder is as effective as midodrine, the standard of care, in the management of orthostatic hypotension. Combining both therapies produces greater improvement in orthostatic tolerance.

Clinical trial registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00223691.

Keywords: autonomic nervous system; blood pressure; hemodynamic; midodrine; orthostatic hypotension; splanchnic circulation.

Conflict of interest statement

Conflicts of Interest/Disclosures

LEO, AD, FJB, RH and IB have submitted a patent application for the use of an automated inflatable abdominal binder as a medical device

© 2016 American Heart Association, Inc.

Figures

Figure 1

Changes from baseline in seated systolic blood pressure (ΔSBP, Panel A), and areas under the curve of standing SBP (ΔAUCSBP, Panel B) after 1 hour postdrug, and orthostatic symptom scores (Panel C) at baseline (pre) and after 1 hour of the intervention (post). The binder was inflated immediately before standing. The total score ranges from 0 to 60, with lower scores reflecting lower symptom burden. Values are expressed as mean±SEM. Overall differences in ΔSBP and ΔAUCSBP among treatment groups were determined by repeated-measures ANOVA (P=0.003 for both comparisons).

Figure 2

Standing systolic blood pressure (SBP) without the binder (No Binder, measured at 1 minute of standing), and with the binder inflated (Binder inflated, measured at 1 and 10 minutes of standing) or deflated (Binder deflated, measured at 11 minute of standing). Values are expressed as mean±SEM.

Figure 3

Changes from baseline in seated systolic blood pressure (ΔSBP, Panel A), and areas under the curve of standing SBP (ΔAUCSBP, Panel B) after 1 hour postdrug, and orthostatic symptom scores (Panel C) at baseline (pre) and after 1 hour of the intervention (post). The binder was inflated immediately before standing. The total score ranges from 0 to 60, with lower scores reflecting lower symptom burden. Values are expressed as mean±SEM.

Figure 4

Changes from baseline in seated SBP (ΔSBP) and standing SBP (1 min standing) after 1 hour of the intervention. The binder, either alone or in combination with midodrine, produced a selective increase in upright SBP (arrows). Values are expressed as mean±SEM.