ASDIN 7th Annual Scientific Meeting

Transcription

1 Partial aneurysmectomy is effective in managing aneurysm-associated complications and preserving dialysis arteriovenous fistulae Ammar Almehmi, MD, MPH Shouwen Wang, MD, PhD University of Arizona and AKDHC-ASC Phoenix, Arizona Arteriovenous Fistula Aneurysm Fistula aneurysm formation is common. The formation of fistula aneurysm is usually multifactorial. Repeated cannulation of fistula for dialysis causes local tissue injury, scarring and weakening. Elevated intra-fistula pressure caused by down stream stenosis and/or excessive inflow are usually contributing factor. Post stenotic dilatation can also cause aneurysm. Fistula aneurysm formation usually does not affect fistula function/cannulation. Fistula Aneurysm-associated Complications Skin and fistula thinning Easy bleeding post dialysis Skin necrosis and erosion Skin scab formation (usually underlying defect) Skin and fistula tissue defects Massive fistula bleeding Aneurysm-associated complications may cause fistula dysfunction, bleeding, even access loss. Basic Pathology of Aneurysmassociated Complications The pathophysiology of aneurysm formation is not well understood. Tissue injury, enzymes release, signaling activations, hemodynamic factors Tissue scarring and thinning Skin ischemia and necrosis Skin tissue defect Fistula tissue defect Fortunately, these complications are usually localized to part of the aneurysm. Faces of aneurysm complications Reported approaches to manage fistula aneurysm and complications Limited literature available Resection and prosthetic interposition (graft) (Georgiadis DS, et al: J Vasc Surg 47:1284, 2008) Aneurysmal fistula reconstruction Aneurysm plication and reshaping with stapler Aneurysmorrhaphy with metal mesh/graft wrap Endovascular stents Endovascular grafts Sadly, many fistulae are abandoned by ligation and/or resection 1

2 Aneurysmal fistula reconstruction Reconstruction with exoprosthesis 19 pts, aneurysmal fistulae 4-7 cm in diameter, skin breakdown (10), bleeding (4), infection (2), Thrombosis, poor flow Resect redundant length, reduce diameter, reconstruct fistula Median 23 mo f/u, median primary patency 14 mons two ligated for infection, one thrombosed, two died, 3 lost to f/u Woo K, et al. J Vasc Surg 51:921, pts, expanding/pain (7), frequent bleeding or skin damage (8), stenosis (2), high flow (16) 12 mo f/u, primary patency 93%, 2 fail, 12/16 reduced flow, 4 re-op Berard, et al: EJVES 40:100, 2010 Fistula aneurysm plication, stapling, perivascular mesh and graft Endovascular stents/grafts for aneurysm 15 cases, uncomplicated, aneurysm reduction Lo HY and Tan SG: Ann Acad Med Singapore 2007;36:851-3 Reshaping with surgical stapler: Pierce GE, et al: Vasc Endovasc Surg 41:55, 2007 Hakim NS, et al: Int Surg 82:376, 1997 Perivascular mesh: Grauhan, et al: Eur J Vasc Endovasc Surg 21:274, 2001 Perivascular graft: Balaz, et al: J Vasc Access 9:81, 2008 Yevzlin AS, Maya ID, Asif A: ACKD 16:352, 2009 (review) Shrilkhande A, et al: SID 22:97, 2009 (case) Mantha ML, et al: KI 76:918, 2009 (case) Keeling AN, et al: SID 21:553, 2008 (case, graft, stent + thrombin) Allaria PM, et al: JVA 3:85, 2002 (case, Wallgraft endoprosthesis) Najibi S, et al: J Surg Res 106:15, 2002 (graft/fistula, 10) Vesely TM: JVIR 16:1301, 2005; Barshes NR, VES 42:228, 2008 (graft) May work, very limited Difficult to work for fistula Affect cannulation Leave lump in place Other complications (clots, infection, occlusion) Do not use when skin defect Should be cautious with use Take a closer look and think twice Partial aneurysmectomy is a practical approach Pathological changes related to complications are usually localized. Extra tissue of aneurysm can be used for repair. Removal of diseased skin and fistula is essential to promote tissue healing. Defects of fistula and skin needs to be properly repaired. With healthier tissue, primary healing is usually achieved. Courtesy of Dr. Shyam Colattur of AKDHC 2

3 Fistula Aneurysm Repair-CP Aneurysm repair - case 2 skin hole and fistula defects Aneurysm repair - case 3 skin scab and fistula defect Fistula aneurysm repair case 4 skin necrosis and fistula defect - indications Active bleeding (skin and fistula hole) 15%(3) Scab/necrosis in danger of bleeding (usually associated with fistula defect) 45%(9) Skin necrosis/erosion 15%(3) Skin and fistula thinning 25%(5) total 100%(20) - clinical data Gender: 60% male Age: 56.7 ± 16.2 Diabetes: 45% Hypertension: 100% Fistula age: 81.2 months (20-222) Upper arm brachial cephalic 90% Forearm radiocephalic 10% 3

4 - clinical outcome Follow-up length: 4.7 ± 3.8 months (1-15 months) All continued dialysis using their current fistula without interruption. All had primary skin healing All fistula functional during follow up period. Two patient died of non-procedure related causes at 3 months after aneurysm repair with functional fistula (cardiac arrests). - conclusion Partial aneurysmectomy is an effective, reliable approach to manage fistula aneurysm-associated complications. Autogenous tissue is preserved and no prosthetic material is introduced. Targeted and localized surgery does not interfere with fistula cannulation. No need for catheter. Partial aneurysmectomy can preserve fistulae and extend their life-span. When to intervene? Most fistula aneurysms do not need intervention. Indications (when there are problems): Bleeding At high risk for bleeding Skin defect/erosion Progressively expanding Excessive fistula flow Thrombosis Significant cosmetic issues What is an ideal intervention for aneurysm-associated complications? Preserves fistulae and their function Easy to learn and apply Safe and fast to accomplish Reliable, with predictable outcomes Economical Does not introduce prosthesis Does not affect cannulation - no catheter Does not leave undesirable mass/lump Is applicable to most of the problems Motto: Nothing is better than a person s own tissue. When you see these faces, Which option to choose? 1. Fistula ligation and new access 2. Aneurysm resection and bridging graft 3. Fistula reconstruction 4. Fistula reconstruction with exoprosthesis 5. Aneurysm plication or stapling 6. Aneurysmorrhaphy with mesh/graft wrap 7. Endovascular stents/grafts placement 8. Partial aneurysmectomy and repair 4

5 Individualize the choice based on what is best for the patient s specific need. Thank you for your attention Questions? AV graft hole repair 5