Malignant venous thrombosis - Ep.2/2 - SLICE Worldwide 2022

Technical issues in Cerebral venous sinus thrombosis

Introduction:

Cerebral venous sinus thrombosis mostly affects young adults, and endovascular treatment is not shown to be beneficial. However, EVT is currently contemplated as a rescue technique in several severe cases in which interventionalist rely on off-label use of devices developed mostly for arterial ischemic stroke but also for several different venous pathologies. While there is no exact technique, and literature data is often restricted to case reports and small series, technical aspects complementary to this Slice Issues are further discussed.

Problems faced with current devices and evidence for several techniques(1):

• Dural venous sinus diameter is around 10 mm, while:
  1. Typical aspiration catheter diameter is 2-3mm
  2. Biggest stents are approximately 6 mm
• This discrepancy makes complete thrombus removal unlikely. However, several experts say that this is not necessary and that the goal of the treatment is to create a channel inside the thrombosed sinus that will facilitate the action of systemic anticoagulation.
• A recent review identified 42 studies. 30 reported a combination of intravenous local thrombolysis and mechanical thrombus debulking, while 8 studies used intravenous thrombolysis only. Two studies did just mechanical debulking. Due to the heterogeneity and the type of this studies an optimal technique cannot be described.
• Aspiration and stent-retriever technique: due to the experience with aspiration catheters and stent-retriever use in acute ischemic stroke. Several authors advise using the same technique, either by employing several passages of simple aspiration in the thrombus mass, to create a channel and maceration of the clot or by performing several pinching maneuvers with 1 or even 2 large and long stents (6x40mm) in the thrombus mass. Several small boluses of tPA inside the clot burden frequently but inconsistently aid this technique.
• This classic technique is frequently helped by deploying a 6x40mm stent in a far distal location and performing several passes of aspiration on its pusher with the aspiration catheter.
• Angiojet technique: Angiojet uses hydrodynamic thrombolytic action through high-velocity saline jets. The aspiration force then draws the thrombus debris to the catheter inflow zone, where it is evacuated from the body through the catheter. The device is reportedly stiff and bulky, and navigation may be a problem. However, this is starting to be improved with the more frequent use of large-bore catheters 0.88, which are easier to navigate inside the dural sinuses and can be used to deliver the Angiojet catheter in the desired location. Thereby unsheathing the catheter in the thrombus mass. Several authors also infused the thrombus with a mix of alteplase or Tenecteplase.(2)
• Fogarty balloon technique: The technique is exemplified in the accompanying video. 3 or 4 Fr. Fogarty balloons are navigated distal to the clot location, inflated, and retrieved in the jugular vein. Access is usually through a 6-Fr jugular sheet. A 4-Fr multihole catheter is navigated through the thrombus, and 5-10mg of Tenecteplase is injected through it before performing an embolectomy. The authors do not try to extract the clot from the patient but leave it to lise in the jugular veins. Apparently, pulmonary embolism is not a major issue, but adequate literature data is still lacking.(3)

Conclusion

Current data regarding an optimal approach for CVST thrombosis are lacking. Despite numerous published case reports and techniques, due to the unknown benefit of the procedure, a cautious approach would be to use devices that one is familiar with and escalate depending on the result and the severity of the patient. Current silicon models offer the chance to test different techniques and are advised before using novel devices with whom we, as neurointerventionalist, are not familiar directly in patients.

Bibliography:

1.           Goyal M, Fladt J, Coutinho JM, McDonough R, Ospel J. Endovascular treatment for cerebral venous thrombosis: current status, challenges, and opportunities. J Neurointerv Surg. 2022 Aug 1;14(8):788. 

2.           Bress A, Hurst R, Pukenas B, Smith M, Kung D. Mechanical thrombectomy for cerebral venous sinus thrombosis employing a novel combination of Angiojet and Penumbra ACE aspiration catheters: the Triaxial Angiojet technique. Journal of Clinical Neuroscience. 2016 Sep 1;31:196–8. 

3.           Frei D, Huddle D, Bellon R, Dooley G. O-009 Mechanical balloon thromboembolectomy for the treatment of cerebral venous sinus thrombosis (CVT): a restropsective analysis of safety and efficacy in 65 consecutive patients. J Neurointerv Surg. 2011 Jul 1;3(Suppl 1):A4.