Abstract Details

Title Initial Orthostatic Hypotension in Patients with Postural Orthostatic Tachycardia Syndrome

Topic Autonomic Disorders

Presentation(s) P03 - (-)

Poster/Presentation
Number 039

Objective

Background BACKGROUND: Patients fulfilled POTS criteria and were highly symptomatic. Beat-to-beat systolic blood pressure (SBP) and interbeat intervals (IBI) were measured by the Finapress device.

Design/Methods DESIGN/METHODS: Both groups rested in the supine position for 5 to 10 minutes before they were asked to stand up. We measured supine basal heart rate (HR) in beats per minute, basal systolic blood pressure (bSBP) in mmHg, the peak increase of HR upon standing (HRp), the peak fall of SBP (SBPpf), the time to the onset of recovery of the SBP (total fall time, TFt) in seconds and finally, the recovery time of SBP until a stable baseline (Rt).

Results RESULTS: Patients fulfilled the criteria of Wieling of a fall of SBP greater than 40 mmHg in the first 15 seconds after assuming the upright posture. Basal HR, TFt, Rt and SBPpf were significantly higher in the patients than in controls. HRp was significantly increased in the patients as compared to controls.

Conclusions CONCLUSIONS: The increase in TFt probably also contributed to the fall in SBP. The delayed Rt indicates a defect in the baroreflex vasosympathetic action and therefore sympathetic damage to the blood vessels. The increase in HR was only partially baroreceptor mediated in 10 patients as the SBP recovered but the HR remained elevated. In two patients both SBP and HR remained elevated (hyperadrenergic POTS). In two patients the SBP remained below the basal SBP and therefore a baroreceptor cardiosympathetic tachycardic action seems plausible. The tachycardia appears to be mediated by a hyperactive cardiosympathetic baroreceptor reflex. A defect in the cardiovagal baroreceptor reflex is also likely.

Authors/Disclosures
Rodolfo C. Callejas-Rojas, MD (Neuro Sleep Klinik) PRESENTER	No disclosure on file
Bruno E. Vidal, MD (Instituto Nacional de Ciencias Médicas y Nutrición)	No disclosure on file
	No disclosure on file
Lauri S. Soinne, MD, PhD, FAAN	Dr. Soinne has nothing to disclose.

��ɫ��

��ɫ��