Thread by @aishaikh

💥 Dialysis Access Associated Venous Thoracic Outlet Syndrome (VTOS) is a rare but under-recognized cause of central vein stenosis in dialysis patients
⚡️Tweetorial on Dialysis Access Associated VTOS 👇🏽
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@ASDINNews
@MedTweetorials
#VascularAccessPearls

💥Venous Thoracic Outlet Syndrome
is due to:
⚡️Subclavian Vein stenosis caused by
it’s compression in the thoracic
outlet
⚡️Thoracic outlet is formed by the 1st
Rib, Clavicle & Subclavius
muscle👇🏽
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💥 Subclavian vein stenosis due to thoracic outlet compression can occur in healthy individuals & can present with:
⚡️Intermittent positional venous obstruction (McCleery Syndrome)
⚡️Venous thrombosis (Paget-Schroetter Syndrome)
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💥Take a look at this image posted by @paulgamboad that demonstrates the the phenomenon of venous compression at the thoracic outlet in a healthy individual 👇🏽

https://twitter.com/paulgamboad/status/1159821239118159873?s=21

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💥 In dialysis patients with an AV access, the subclavian vein is particularly vulnerable to stenosis due to high venous outflow & associated turbulence in the setting of mechanical compression by the 1st rib & clavicle at the thoracic outlet👇🏽
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💥Dialysis Vascular Access associated VTOS can present with these symptoms:
⚡️Arm swelling👇🏽
⚡️ High venous pressure (on dialysis)
⚡️ Prolonged bleeding from the AV
access during or after cannulation
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💥Venous stenosis in dialysis AV access is typically Rx with endovascular interventions (angioplasty/stent)
⚡️But venous stenosis due to VTOS can be resistant to angioplasty/stent & may require surgical bone decompression
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💥Look at the ‘nut-cracker’ effect of the first rib & clavicle on the stent placed in the subclavian vein at the thoracic outlet
⚡️This can lead to stent fracture & persistent stenosis
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💥Surgical bone decompression for venous stenosis at the the thoracic outlet can be done by:
⚡️1st Rib Resection
⚡️ Medial Claviculectomy
⚡️Sternoclavicular junction rotation by partial sternotomy
💥Rarely vein bypass is performed
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💥Summary:
⚡️Dialysis Access Associated VTOS
can cause debilitating symptoms
⚡️Subclavian vein stenosis can be
resistant to angioplasty & stenting
⚡️In such patients, surgical
decompression procedures may
need to be considered
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