What procedure is recommended for an arteriovenous (AV) fistula thrombosis?

Management of Arteriovenous Fistula Thrombosis

For arteriovenous fistula thrombosis, endovascular techniques including mechanical thrombectomy and thrombolysis with angioplasty of underlying stenosis are recommended as first-line treatment, with surgical thrombectomy reserved for specific cases such as juxta-anastomotic stenoses in forearm AVFs. 1

Immediate Management Approach

• Thrombosed fistulae should be treated as soon as possible after detection to increase likelihood of successful restoration and avoid temporary catheter placement 1
• Initial evaluation should include assessment of the location and extent of thrombosis through clinical examination and imaging 1
• Treatment selection depends on:
  • Location of thrombosis and underlying stenosis
  • Time since thrombosis occurred
  • Local expertise and available resources 1

Endovascular Techniques (First-Line)

• Endovascular management is preferred as first-line therapy over surgical techniques for most AV fistula thromboses 1

• Success rates for endovascular techniques are greater than 90%, compared to only 65% for surgical thrombectomy 1

• Options include:

  • Mechanical thrombectomy (suction thrombectomy, balloon thrombectomy, clot maceration) 1
  • Pharmacologic thrombolysis using tissue plasminogen activator 2
  • Combination of mechanical and pharmacologic approaches 1
  • Balloon angioplasty of underlying stenosis 1

• Fistulography must be performed to identify and correct underlying stenosis, which is present in up to 85% of thrombosis cases 1

• Stent placement may be considered for central vein stenosis or to decrease early recurrence of stenosis/thrombosis 1

Surgical Techniques

• Surgical thrombectomy is performed using a Fogarty thrombectomy catheter with retrograde digital expression of thrombotic material 1
• Surgery is preferred specifically for:
  • Forearm AVFs with juxta-anastomotic stenoses, mainly by placement of a new anastomosis 1, 3
  • Cases where endovascular techniques have failed 1
• When both artery and vein are thrombosed, conversion from side-to-side to end-to-side anastomosis may be attempted 1

Location-Specific Approach

• For juxta-anastomotic stenoses in forearm AVFs: Surgical thrombectomy with placement of new anastomosis is preferred 1
• For more proximal/central thromboses: Endovascular techniques are preferred 1
• For thrombosis with concurrent central venous stenosis: Endovascular techniques with possible stent placement 1

Timing Considerations

• AVF function may be successfully reestablished up to one week after thrombosis occurs, but treatment should be initiated as soon as possible 1
• Early intervention (within 24-48 hours) is recommended to maximize success rates 1
• Delay increases risk of:
  • Need for temporary catheter placement
  • Progressive growth of thrombus making procedures more difficult
  • Increased damage to endoluminal layer from prolonged contact with thrombus 1

Expected Outcomes and Follow-up

• Technical success rates for endovascular techniques: 75-94% 1
• Primary patency rates after successful intervention:
  • Percutaneous techniques: 30-40% at 90 days 1
  • Surgical techniques: approximately 50% at 6 months and 20% at 1 year 1
• Secondary patency rates after intervention:
  • 54-80% at 6 months 4, 5
  • 70-77% at 12 months 6, 7
• Regular monitoring for recurrent stenosis or thrombosis is essential 1

Common Pitfalls and Considerations

• Failure to identify and treat underlying stenosis will result in rapid repeat thrombosis 1

• Excessive force during thrombectomy can damage vessel walls or expel clots into circulation 2

• Vigorous suction should be avoided during attempts to determine catheter occlusion 2

• If thrombosis recurs more than twice within a month, consider:

  • Hypercoagulability testing 1
  • Vascular surgery consultation for access revision 1
  • Flow/d-dimer ratio <0.63 may predict recurrent thrombosis after surgical thrombectomy 8

• If restoration fails, a tunneled dialysis catheter may be needed temporarily while planning for a new access creation 1