Superior vena cava stenting

Superior vena cava stenting is an interventional procedure used for the management of superior vena cava (SVC) obstruction.

Indication

This procedure is indicated in severe symptomatic SCV obstruction with failure of the medical treatment (e.g. corticosteroids, anticoagulation therapy, diuretics, chemotherapy).

Preprocedural assessment

• clinical history

• pre-procedure phleboscanner

  • analyze the length and diameter of the stenosis to determine the choice of the stent to be used

  • verify patency of the subclavian and brachiocephalic veins, for navigation

• If the patient has stenosis around a central venous catheter

  • consider displacing it using a retained-fragment retriever (placement in the IJV, leaving room for stent placement, and then using the retriever again, to replace it back in the stent)

  • no need for displacement if the catheter allows the placement of the stent

Patient preparation

• informed consent

• clear fluids per oral for 4-6 hours prior to the procedure

• IV access

• monitoring

Procedure

• If the patient is not under anticoagulation therapy, administration of a bolus of 3000 IU of heparin is needed

• local anesthesia or sedation

• ultrasound-guided percutaneous venous access

  • femoral venous route: better pushability, better position for the radiologist

  • upper arm vein route (right basilic/brachial veins) ¹

  • right subclavian vein approach¹

  • internal jugular vein

  • if the patient has a central venous catheter, it could be used for access if the stenosis is too tight, and cannot get through other routes

• introduce a large vascular sheath catheter in the selected vein (6-10 F)

  • depends on the size of the stent that will be used

• insert a navigation wire with a

  • pigtail catheter: better for phlebography

  • vertebral catheter

• after reaching target stenosis, a phlebograpam should be peformed

  • to determine the size of stent to be placed

• angioplasty

  • insertion of an Amplatz wire and mounting a 3-5 mm diameter balloon

  • inflation of the balloon in the target stenosis

  • if the stenosis is benign, an angioplasty could be sufficient and there is no need for a stent ²

  • If the stenosis is tight, an angioplasty could be useful to dilate the stenosis and place the stent

  • could be performed before and after stenting, through the stent

• stenting using a

  • uncovered, self-expandable metal stent - for a smooth opening and reduced risk of SVC rupture

  • diameter between 10-16 mm - should be <16 mm to reduce the risk of SVC rupture

  • the length should cover the stenosis, and reach the brachiocephalic trunk

  • high radial force is prefered for tight stenoses

• if a pharmacomechanical thrombolysis is preferred

  • a pigtail catheter should be used for high-rate injections

• end procedure phlebogram

  • to confirm the stent position and efficacy

  • the smallest collateral pathways should disappear

  • persistance of the the bigger collaterals is normal

Medical prescrption

There is no consensus on wich precription the patient should get after procedure, but generally, patients get antiplatelet drug and anticoagulation therapy for at least 3 months.

Follow up

Clinical and CT follow-up at 1 month and 6 month - no need for a multiphased phleboscanner, a venous phase is sufficient

Complications

• acute

  • pulmonary embolism

    • due to thrombus migration during angioplasty or stenting

  • SVC rupture

    • intra-pericarial rupture causes cardiac tamponade: requires pericardial drainage

    • exta-pericardial rupture: mediastinal hemorrhage

    • acute decompensated heart failure / overload syndrome

• chronic ³

  • stent thrombosis

  • stent migration

  • stent fracture

  • Inferior laryngeal nerve compression