Defining the factors leading to stroke due to retrograde embolism in arterial thoracic outlet syndrome by literature search and report of two cases

Abstract

Context: Stroke due to retrograde embolization in a case of arterial thoracic outlet syndrome (aTOS) is rare, and little is known about predisposing factors. Objective: The aim of this study is to analyze the predisposing factors and mechanisms of stroke in aTOS based on literature survey and experience with two cases. Materials and Methods: – Data Sources and Selection: Databases MEDLINE, PubMed, Scopus, and Cochrane Library were searched, supplemented by scanning of reference lists of relevant publications. All publications with subclavian artery/axillary artery stenosis/occlusion, either due to bony and/or muscular abnormality, in the thoracic outlet, with stroke, till January 2020 were included. Data Extraction: The clinical and anatomical details such as gender, age, side affected the type of stroke (anterior/posterior), bony/skeleton abnormality, upper limb symptoms, and their duration, were noted and analyzed. Data Synthesis: A systematic analysis of the accessed reports was performed. Statistical Analysis: The measure of the significance of the association of various factors was calculated with z-test. Results: Forty-eight articles describing 58 patients were identified. Fifty-five patients were analyzed. The involvement of the right upper limb (P = 0.00001), age <40 years (P = 0.00001), and the presence of upper limb ischemic symptoms (P = 0.00001) significantly predispose to the development of stroke in aTOS. Twenty-seven percent had a recurrent stroke. Conclusions: Stroke is a rare complication of aTOS. A possible explanation exists for retrograde embolism; however, validation is required by further studies. Stroke in young with upper limb ischemia or absent pulses merits a search for aTOS.

Keywords

• arterial thoracic outlet syndrome
• retrograde embolism
• stroke