CHARACTERIZATION OF ARTERIAL STIFFNESS IN PATIENTS WITH POSTURAL ORTHOSTATIC TACHYCARDIA SYNDROME AND EHLERS-DANLOS SYNDROME JOINT HYPERMOBILITY SYNDROME TYPE III

Abstract

Postural orthostatic tachycardia syndrome (POTS) is characterized by symptoms of orthostatic intolerance associated with an exaggerated increase in heart rate (HR) on standing. Recently, researchers have been reported that patients with Joint Hypermobility Syndromes, genetic disorders that affect collagen synthesis and deposition such as Ehlers-Danlos syndrome type 3 (EDS-3), have associated symptoms of POTS. The combination of these disorders may produce an altered vascular phenotype that has not been previously investigated. To characterize arterial stiffness in POTS+EDS-3 individuals and compare to healthy age-sex-matched controls (CON). Nine clinically diagnosed individuals with POTS+EDS-3, and 9 CON participated in the study. Vascular assessments were conducted after 10 minutes of supine rest. Primary outcome measures include central, upper limb, and lower limb arterial pulse wave velocity (PWV) obtained using applanation tonometry; local carotid artery distensibility measured with simultaneous ultrasound imaging and applanation tonometry; and carotid intima-media thickness (IMT) measured with ultrasound imaging 2-5 cm proximal to the carotid bifurcation. No differences were observed between the POTS+EDS-3 and CON groups in carotid elasticity including compliance, distensibility and beta-stiffness. There were also no differences between groups in regional PWV including central, upper limb and lower limb pulse wave velocity. There were no significant differences in IMT between groups. Arterial stiffness is not significantly different between individuals with POTS+EDS-3 and CON. Vasoactive medications used by POTS+EDS-3 patients may preclude the detection of arterial stiffness differences. Further investigations should increase the sample size and be conducted in conditions absent of vasoactive medications.