Incidence of Thoracic Outlet Syndrome in Patients With Postural Orthostatic Tachycardia Syndrome

Abstract

Thoracic outlet syndrome (TOS) refers to a constellation of symptoms resulting from neurovascular compression at the thoracic outlet, causing some combination of pain in the neck and upper extremity, weakness, sensory loss, paresthesia, swelling, and discoloration. Classification of TOS would depend on the anatomical structure that is compressed: venous TOS (VTOS)—compression of Subclavian vein; arterial TOS (ATOS)—compression of subclavian artery; and neurogenic TOS (NTOS)—compression of brachial plexus. Postural Orthostatic Tachycardia Syndrome (POTS) is characterized by orthostatic tachycardia that develops in the absence of orthostatic hypotension, with a symptom duration of >6 months. POTS is now known to be commonly associated with Ehlers-Danlos Syndrome (EDS), thereby raising speculation about the extent of prevalence of TOS symptoms in EDS patients. The aim of the study was to quantify the influx of patients with POTS, reporting symptoms of arm fatigue with or without numbness and tingling. The symptoms were quantified initially by conducting postural maneuvers that would reproduce the symptoms, to rule-in the possibility of TOS and further confirmed by using ultrasonography in upper limbs as the imaging modality of choice to evaluate arterial and/or venous compression. This study also looks at the presence of a concurrent diagnosis of EDS among the symptomatic patients who test positive for TOS.