Use of Valsalva Maneuver to Detect Late-Onset Delayed Orthostatic Hypotension

Background: Standard autonomic testing includes a 10-minute head-up tilt table test to detect orthostatic hypotension. Although this test can detect delayed orthostatic hypotension (dOH) between 3 and 10 minutes of standing, it cannot detect late-onset dOH after 10 minutes of standing. Methods: To determine whether Valsalva maneuver responses can identify patients who would require prolonged head-up tilt table test to diagnose late-onset dOH; patients with immediate orthostatic hypotension (onset <3 minutes; n=176), early-onset dOH (onset between 3 and 10 minutes; n=68), and late-onset dOH (onset >10 minutes; n=32) were retrospectively compared with controls (n=114) with normal head-up tilt table test and composite autonomic scoring scale score of 0. Results: Changes in baseline systolic blood pressure at late phase 2 (∆SBP VM2 ), heart rate difference between baseline and phase 3 (∆HR VM3 ), and Valsalva ratio were lower and pressure recovery time (PRT) at phase 4 was longer in late-onset dOH patients than in controls. Differences in PRT and ∆HR VM3 remained significant after correcting for age. A PRT ≥2.14 s and ∆HR VM3 ≤15 bpm distinguished late-onset dOH from age- and sex-matched controls. Patients with longer PRT (relative risk ratio, 2.189 [1.579–3.036]) and lower ∆HR VM3 (relative risk ratio, 0.897 [0.847–0.951]) were more likely to have late-onset dOH. Patients with longer PRT (relative risk ratio, 1.075 [1.012–1.133]) were more likely to have early-onset than late-onset dOH. Conclusions: Long PRT and short ∆HR VM3 can help to identify patients who require prolonged head-up tilt table test to diagnose late-onset dOH.