The Emerging Use of Endovascular Stenting in Primary Aortoduodenal Fistula

1. The Emerging Use of Endovascular Stenting in Primary Aortoduodenal Fistula YU Hok Yee Harry Pamela YoudeNethersole Eastern Hospital Joint Hospital Surgical Grand Round 16th April 2011

2. Introduction • First described by Sir Astley Cooper in 1822 • About 300 reported in literature • Incidence • 0.04 – 0.07% in large autopsy study • 3% of massive GI bleed, 6% of fatal GI bleed • Mortality: 67%; inevitable fatal without operative intervention • Primary vs. secondary • Can occur anywhere between oesophagus, commonest in duodenum (80%); can be multiple • Mostly associated with AAA (>80%), infection; and other rarer causes Edgard et al, 2001 Kane et al, 1955 Farber et al., 2001 Sevastos et al, 2002 Sintler et al, 2008

3. Clinical Presentation • Presentation of “Classical Triad” is minority (11%) • Gastrointestinal bleed (94%): “herald” bleeding  massive haemorrhage and exsanguination • Abdominal pain (48%) • Pulsating abdominal mass (17%) • Non-specific symptoms • Suspicious in patient • Known AAA • Unexplained GI bleeding, over 50-year-old • Upper endoscopy & CT scan as the mainstay of investigation modalities Saers et al, 2005 Sintler et al, 2008 Mylona et al, 2007

4. Management • Prompt operation is only the only mean to save patient’s life • Treatment aim • To control bleeding • To eradicate infection • To maintain adequate distal perfusion Montgomery et al, 1996

5. Management • Classical methods: • Debridement of infected tissues together with • Primary repair of intestinal defect, with • Aneurysmorrphaphy; or, • Replacement of aneurysm with prosthetic graft • Aortic ligation with extra-anatomical bypass, e.g. axillary-bifemoral graft

6. Management-Problems with Conventional Treatment • Overall mortality: 63% • Complications • Aortic stump rupture: 10 – 50% • Limb loss, resulting in amputation: 5 – 25% • Time consuming operation: extra strain to a stressful condition Farber et al., 2001 Burks et al, 2001

7. Emergence of Endovascular Aortic Repair (EVAR) in Aortoduodenal Fistula

8. Emergence of EVAR • First reported by Burks in 2001 • 2 of 7 patients with primary aortoenteric fistula • 82-year-old, male, hypertension, coronary artery disease, 10cm AAA • Treated with Aortouniiliac stent graft • Immediate cessation of bleeding achieved • Died 13 months due to myocardial infarction • Several case reports with similar success

9. EVAR in Aortoduodenal Fistula- Advantages • Rapid control of bleeding • Minimal physiologic insult to patient • Avoidance of operating in hostile abdomen • Straightforward and speed of procedure • Eliminating complications associated with open surgical repair • Lower perioperative complication incidence • Shorter hospital stay and more likely to discharge home Roche-Nagle et al, 2009 Chan et al, 2005

10. EVAR in Aortoduodenal Fistula- Candidate Selection • Pre-operative CT scan: diagnosis and planning • Significant co-morbidities / High-risk for conventional operation • Medical: cardiopulmonary, renal, etc. • Surgical: hostile abdomen • Expertise for emergency EVAR • Stent graft in immediate availability

11. EVAR in Aortoduodenal Fistula- Complications • Persistent sepsis • Repeat intervention or image-guided drainage • Fungal infection, e.g. Aspergillus • Long-term (or life-long) antibiotics • Medical: underlying co-morbidities of patient • Persistent bleeding • No reported incidence • Case report: unsuccessful result not reported? • Secondary aortoenteric fistula

12. Stent Graft in Infected Region- A Contraindication? • Against general surgical principle: putting endovascular graft in infected environment • Lack of excision and debridement of infected nidi • Arguments • Low bacterial load over aortic side due to direction of blood flow: bacteria washed away to enteric side • Increased infection resistance by stent-grafts compared to standard polyester grafts • Endovascular stent graft: 0.43% • Conventional open repair: 0.5 – 3% • Adjunct techniques to suppress local infection: antibiotics; CT-guided drainage, injection of fibrin, cyanocylate sealants, local antibiotic cleansing Ducasse et al 2004

13. Haemostasis is the Key • Basic principle of resuscitation: Airway, Breathing, Circulation • Basic principle to manage gastrointestinal bleed: Resuscitation, identify the bleeding, stop the bleeding • High mortality and morbidity with conventional treatment: to achieve haemostasis and eradicate infection in haemodynamically unstable patient • EVAR allows expeditious bleeding control with less physiological insult • Infection can be dealt in later stage of management • Traditional repair after EVAR remained an option Verhey et al, 2006

14. Mortality- Comparison between Types of Operation Saers et al. 2005

15. EVAR in Aortoduodenal Fistula- Definitive vs. “Bridging” • Debatable • Particular on “infection” issue • Endovascular stent does not include intestinal repair • Life-long antibiotics • Long-term suppression of sepsis • Death mainly due to coexistent cardiopulmonary disease • Adjunctive treatment may contain sepsis • Percutaneous drainage • Bowel diversion Burks et al. 2001

16. SummaryEVAR in Primary Aortoduodenal Fistula • Rare disease carries high mortality • Conventional therapy • Aim to control bleeding, maintain distal circulation and eradicate infection • Very high mortality • EVAR can have rapid control of bleeding • Multiple adjunct techniques available to control infection • Definitive or “bridging” therapy depends on scenario