Abstract P337: Valsalva Maneuver And Detection Of Late-onset Orthostatic Hypotension

Delayed orthostatic hypotension (dOH) is defined as OH occurring ≥3 minutes of standing. Standard autonomic testing now includes a 10 min head-up tilt (HUT) and detects “early” dOH, but “late” onset dOH (occurring ≥10 min of standing) remains a diagnostic challenge. To determine if the Valsalva maneuver (VM) can identify patients that would require a prolonged HUT (>10 min) to diagnose late dOH, we analyzed a database of 2,498 patients who underwent autonomic function tests (AFTs) in Korea University Anam Hospital between 2016-2022. Patients with diagnosis of OH (onset of OH VM2 ) and in heart rate at phase 3 (ΔHR VM3 ), pressure recovery time at phase 4 (PRT), Valsalva ratio (VR) and baroreflex sensitivity (BRSa and BRSv), were compared among groups. We found that ΔSBP VM2 , ΔHR VM3 and VR were lower in late dOH patients compared to controls (PVM3 remained significant. A receiver operating characteristic analysis revealed that cut-offs values of PRT ≥2.14 sec and ΔHR VM3 ≤15 bpm distinguished late dOH from an age and gender matched controls (PVM3 (OR=0.149 [0.056-0.398]) were more likely to have late dOH. In conclusion, our results in late dOH patients showed that PRT and ΔHR VM3 differ from those of controls, early dOH and OH, suggesting a milder form of autonomic dysfunction. These VM parameters could be used to identify patients who need prolonged >10min HUT to diagnose late-onset OH.