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Ex Vivo Repair of a Large Renal Artery Aneurysm and Associated Arteriovenous Fistula
Papers Presented to the Southern
California Vascular Surgical Society
ANNALSo/ VASCULAR SURGERY --{
InteTnatioaalJeurnll of VascuLarSurgery ]
Ex Vivo Repair of a Large Renal Artery Aneurysm and Associated Arteriovenous Fistula Gustavo Torres, MD, Thomas T. Terramani, MD, and Fred A. Weaver, MD, Los Angeles, California
The development of a renal artery to vein arteriovenous fistula due to a large extraparenchymal renal artery aneurysm is uncommon. Previous surgical experience with this entity is limited. Based on the existing surgical literature, nephrectomy has been the treatment of choice. We report preservation of the kidney by surgical correction of this entity using ex vivo "bench" repair in a middle-aged female with fibromuscular dysplasia of the renal artery. The technique, results, and recommendations for surgical management are discussed.
INTRODUCTION Fibromuscular dysplasia (FMD) of the renal arteries is a leading cause of renovascular hypertension. FMD most c o m m o n l y affects w o m e n ages 35-55 and includes a variety of hyperplastic and fibrosing lesions of the intima, media, a n d / o r adventitia. Medial fibrodysplasia is the most c o m m o n type, and is present in approximately 85% of patients with FMD of the renal artery. Angiographically it is likened to a string of beads that involves the mid- to distal main renal artery with extension to the firstorder segmental branch vessels in approximately 25% of patients. 1 The association of renal artery aneurysms with medial fibrodysplasia FMD is well
Department of Surgery, Division of Vascular Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA. Presented at the Annual Meeting of the Southern California Vascular Surgical Society, Santa Barbara, CA, April 27-29, 2001. Correspondence to: F.A. Weaver, MD, USC School of Medicine, 1510 San Pablo Avenue, Suite 514, Los Angeles, CA 90033-4612, USA. Phone: 323-442-5907, Fax: 323-442-5735 E-mail: [email protected]. Ann Vasc Surg 2002; ld: 141-144 DO[: lO.IO07/slOO16-OOl-O155-z 9 Annals of Vascular Surgery Inc. Published online: February 13, 2002
recognized. However, it is u n c o m m o n , even with large renal artery aneurysms that erosion and fistulization into the adjacent renal vein occurs. This report describes a patient with a giant renal artery a n e u r y s m associated with medial fibrodysplasia complicated by high-outflow fistula into the right renal vein. The patient was treated successfully with preservation of the kidney by orthotopic ex vivo vascular reconstruction. CASE REPORT A 61-year-old female was found on routine urinalysis to have microscopic hematuria. Her past medical history was significant for hypertension for 20 years, mitral valve prolapse, atrial tachyarrhythmias, and mild congestive heart failure (CHF) manifested by two-pillow orthopnea. Her medications included Zestril, Atenolol, and Prinivil. To evaluate the hematuria she u n d e r w e n t an abdominal c o m p u t e r t o m o g r a p h y (CT) scan, which demonstrated a large right renal artery a n e u r y s m and enlarged right renal vein. This prompted an abdominal aortogram, which showed a large saccular right renal artery a n e u r y s m measuring 3.2 cm located in the renal hilum, an arteriovenous fistula
141
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Fig. 1. Angiogram demonstrating large right renal artery with dysplastic changes and a large saccular aneurysm. from the a n e u r y s m to the right renal vein, and an 8-turn right renal artery with a beaded, corrugated appearance consistent with medial fibrodysplasia (Figs. 1 and 2). The left renal artery was normal in size and w i t h o u t evidence of FMD. She was then referred to University of Southern California (USC) University Hospital for further evaluation and treatment. At initial evaluation her blood pressure was 190/90; she was in n o r m a l sinus r h y t h m with a II/VI cardiac systolic ejection m u r m u r . A pulsatile right-sided abdominal mass was evident and associated with a machine-like c o n t i n u o u s abdominal bruit. Trace-pitting pretibial edema was observed in both lower extremities. Laboratory data indicated n o r m a l renal function with a blood urea nitrogen (BUN) of 19 and creatinine of 0.9. The patient u n d e r w e n t operative repair t h r o u g h a midline transabdominal approach. Intraoperatively the right renal vein was f o u n d to be dilated to approximately 2.5 times normal caliber. The aneurysm was calcified and appeared to arise from the upper pole first-order segmental branch. The repair of the renal artery was performed using an ex vivo approach that has been previously described. 2 The kidney p a r e n c h y m a was freed from the s u r r o u n d -
Annals o[ Vascular Surgery
Fig. 2. Later phase of angiogram documenting fistulous connection with right renal vein and early visulization of inferior vena cava. ing Gerota's fascia and mobilized on the renal artery and vein pedicle. The origin of the renal artery was identified and the artery was traced u n d e r the cava to the renal hilum. Lumbar branches to the vena cava were ligated to provide access to the renal artery as it coursed posterior to the inferior vena cava. The ureter was mobilized to the pelvic brim, taking care to preserve the periureteral vesssels. Following intravenous administration of heparin, the renal artery at its origin was clamped, oversewn, and divided. A side-biting clamp was placed on the vena cava at the renal vein origin and the vein was divided by taking a small cuff of vena cava. The kidney was lifted from the renal fossa, an atraumatic clamp was applied to the ureter to p r e v e n t renal w a r m i n g from ureteral vessels, and the kidney was flushed t h r o u g h the renal artery with a cold (4~ modified Collins solution until the venous effluent was clear and the p a r e n c h y m a pale. It was placed in a plastic bag and cooled externally with cold laparotomy packs. The a n e u r y s m was opened and the fistulous c o n n e c t i o n to a large upper pole branch of the renal vein was identified. The renal branch was severed from the a n u e r y s m and ligated. The
Vo]. 16, No. 2, 2 0 0 2
a n e u r y s m originated at the branch point of the u p p e r and middle first-order segmental branches. After resection of the a n e u r y s m and proximal dilated m a i n renal artery, a c o m m o n cuff of the two b r a n c h e s was created by suturing the medial walls of the branches together using 7-0 Prolene suture. A s e g m e n t of reverse greater s a p h e n o u s vein, h a r v e s t e d from the thigh, was sutured to the c o m m o n cuff containing the u p p e r a n d mid-segm e n t a l branches. The lower pole b r a n c h was attached to the side of the vein graft at a separate location. The kidney was placed back in its anatomic position, the arterial graft was placed posterior to the v e n a cava, and an end-to-side anastomosis to the infrarenal a b d o m i n a l aorta was performed. The renal vein was reattached to the v e n a cava. The arterial and v e n o u s clamps were released simultaneously a n d the renal p a r e n c h y m a was reperfnsed. Intraoperative duplex e x a m docum e n t e d a satisfactory repair with n o r m a l velocity profiles in the m a i n renal artery a n d vein. Gerotas fascia was closed over the kidney to p r e v e n t torsion. The patient had an u n e v e n t f u l postoperative course; she was discharged on postoperative day 6. At follow-up of 8 m o n t h s her blood pressure was 125/80 on Atenolol only. Renal function (BUN - 8 and creatinine - 0.7) was n o r m a l a n d a renal artery duplex scan s h o w e d a right kidney i0 cm in length with n o r m a l velocity profiles in the right renal artery and vein. She no longer complained of shortness of breath w h e n supine.
DISCUSSION A l t h o u g h FMD of the renal arteries is an u n c o m m o n condition, it is the s e c o n d - m o s t c o m m o n cause of correctable renovascnlar h y p e r t e n s i o n in the United States, accounting for 18-40% of cases. 3 The right renal artery is m o r e c o m m o n l y affected t h a n the left, but bilateral i n v o l v e m e n t is present in the vast majority of patients. The classical FMD finding of "string of beads" usually involves the m i d - m a i n renal artery but can e x t e n d into the segmental branches on occasion. Small and, on occasion, large renal artery a n e u r y s m s are associated with the medial fibrodysplasia type of FMD. However, fistulization to the adjacent renal vein is rarely reported, with only three cases having b e e n d o c u m e n t e d in the English literature. The rarity of fistula f o r m a t i o n is s o m e w h a t surprising, given the proximity of the renal vein and the possibility of vein branches being stretched tautly o v e r the surface of a large a n e u r y s m . 4
Ex vivo repair of re~al arte W aneut3'sm
143
Although renal artery a n e u r y s m s are most c o m m o n l y associated with EMD, they can also occur following renal artery dissection, renal artery t r a u m a , or in association with m e d i u m - s i z e d vessel arteritis. Large, solitary a n e u r y s m s occur less frequently and are most likely congenital. Approximately 90% of renal artery a n e u r y s m s are e x t r a p a r e n c h y m a l and saccular in configuration. Most are a s y m p t o m a t i c at the time of diagnosis. The most c o m m o n complication is rupture. Risk factors for rupture include p r e g n a n c y and hypertension. Indications for operation include s y m p t o m a t i c patients with a ruptured or leaking a n e u r y s m , ane u r y s m s suspected of causing renovascular hypertension, and expansion of an a n e u r y s m or renal p a r e n c h y m a l embolization. For a s y m p t o m a t i c aneurysms discovered incidentally, size determines the need for intervention, with most authors reco m m e n d i n g surgery for a n e u r y s m s >1.5-2.5 cm in diameter. 4,5 There are only three reports in the literature concerning the surgical m a n a g e m e n t of a large e x t r a p a r e n c h y m a l renal artery a n e u r y s m that has fistulized to the renal vein. Two cases presented with acute i n t r a a b d o m i n a l h e m o r r h a g e requiring i m m e d i a t e operation and one case was diagnosed a n d treated electively. Similar to our patient, all three patients at diagnosis had evidence of a central h i g h - o u t p u t arteriovenous f i s t u l a - - n a m e l y diastolic hypertension, a m a c h i n e - l i k e c o n t i n u o u s abdominal bruit, and heart failure. 6-9 The three patients were treated with n e p h r e c t o m y , but these reports were before the t e c h n i q u e of ex vivo reconstruction was refined. In 1975, Belzer et al. described five patients in w h o m the t e c h n i q u e of ex vivo reconstruction was used to surgically treat r e n o v a s c u l a r h y p e r t e n s i o n due to complex branch disease of the renal artery, l~ The advantages of such an a p p r o a c h were optimal vascular exposure in a bloodless surgical field and renal protection from prolonged w a r m ischemia. By establishing renal h y p o t h e r m i a t h r o u g h external renal cooling and flushing of the p a r e n c h y m a with Ringer's lactate at 4~ Belzer was able to minimize renal metabolic d e m a n d . This preserved renal p a r e n c h y m a and function and provided the time needed to reconstruct renal b r a n c h vessels 1 to 3 m m in diameter. Following vascular reconstruction, he placed the reconstructed kidney in the pelvis with arterial and v e n o u s anastomoses to the c o m m o n iliac or hypogastric artery and vein. For renal transplant surgeons such as Belzer, the advantages of the heterotopic position of the kidney included easy
144
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m a n u a l p a l p a t i o n of t h e k i d n e y , easy access for biopsy, use of t h e h y p o g a s t r i c a r t e r y for i n f l o w , a n d ease of r e m o v a l for t r a n s p l a n t r e j e c t i o n , H o w e v e r , in the n o n t r a n s p l a n t p a t i e n t , n o n e of these adv a n t a g e s are o p e r a t i v e . Since t h e k i d n e y c a n be q u i t e easily p l a c e d i n its u s u a l a n a t o m i c location, w i t h the a d d e d b e n e f i t of e l i m i n a t i n g t h e pelvic dissection r e q u i r e d to expose t h e c o m m o n iliac or h y p o g a s t r i c a r t e r y a n d iliac v e i n , D e a n et al. m o d ified Belzer's ex v i v o t e c h n i q u e a n d placed t h e reconstructed k i d n e y in an orthotopic position, a technique that we have adopted with only minor m o d i f i c a t i o n . ~1 Despite t h e s e e m i n g c o m p l e x i t y of ex vivo vascular reconstruction, postoperative complications are r e p o r t e d l y f e w a n d p a t e n c y of t h e r e c o n s t r u c t e d r e n a l a r t e r y a p p r o a c h e s 1 0 0 % . 2'11 O u r p r e v i o u s e x p e r i e n c e w i t h ex vivo r e c o n s t r u c t i o n for a v a r i e t y of r e n a l a r t e r y lesions suggested t h a t it w o u l d e n able v a s c u l a r i s o l a t i o n a n d r e p a i r of o u r p a t i e n t ' s r e n a l a r t e r y to v e i n fistula w i t h m i n i m a l b l o o d loss, renal dysfunction, and morbidity. This is t h e first r e p o r t of a large e x t r a p a r e n c h y m a l saccular r e n a l a r t e r y a n e u r y s m c o m p l i c a t e d b y f i s t u l i z a t i o n to t h e r e n a l v e i n w h i c h was r e p a i r e d u s i n g ex vivo r e c o n s t r u c t i v e t e c h n i q u e s . A l t h o u g h n e p h r e c t o m y is a n a c c e p t a b l e o p t i o n i n the elective setting, ex vivo repair is preferred, since it allows for salvage of r e n a l p a r e n c h y m a w i t h a h i g h d e g r e e of reliability. C o n s e q u e n t l y , n e p h r e c t o m y s h o u l d be r e s e r v e d for p a t i e n t s w h o p r e s e n t i n e x t r e m i s d u e to t h e c a r d i o v a s c u l a r c o m p l i c a t i o n s of t h e
fistula or h e m o r r h a g e f r o m a l e a k i n g r e n a l a r t e r y aneurysm.
REFERENCES 1. Alimi Y, Mercier C, Pellissier JF, et aI. Fibromuscular disease of the renal artery: a new histopathologic classification. Ann Vasc Surg 1992;110:220-224. 2. Hood DB, Weaver FA. Orthotopic ex vivo renal artery reconstruction. Am Surg 1994;60;804-808. 3. Weaver FA, Kuehne JP, Papanicolaou G. A recent institutional experience with renovascular hypertension. Am Surg 1996;62:241-245. 4. Stanley JC, Rhodes EL, Gewertz BL, et al. Renal artery aneurysms: significance of macroaneurysms exclusive of dissections and fibrodysplastic mural dilatations. Arch Surg 1975; 110:1327-1333. 5. Ernst C, Stanley J. Current Therapy in Vascular Surgery, 4th ed. Mosby, St. Louis 2001, pp 760-763. 6. Oxman H, Sheps S, Bematz P, Harrison E. An unusual cause of renal arteriovenous fistuta--fibromuscular dysplasia of the renal arteries. Mayo Clin Proc 1973;48:207210. 7. Maldonado JE, Sheps SG, Bematz PE, et al. Renal arteriovenous fistula: a reversible cause of hypertension and heart failure. Am J Med 1964;37:499-513. 8. Maldonado JE, Sheps SG. Renal arteriovenous fistula. Postgrad Med 1966;40:263-269. 9. Bron K, Redman H. Renal arteriovenous fistula and fibromuscular hyperplasia. A new association. Ann Intern Med 1968;68:1039-1043. 10. Belzer FO, Salvatierra O, Palubinskas A, Stoney RJ. Ex vivo renal artery reconstruction with autotransplamation. Ann Surg 1975;182:456-463. 11. Dean RH, Meacham PW, Weaver FA. Ex vivo renal artery reconstructions; indications and techniques. J Vasc Surg 1986;4:546-552.
California Vascular Surgical Society
ANNALSo/ VASCULAR SURGERY --{
InteTnatioaalJeurnll of VascuLarSurgery ]
Ex Vivo Repair of a Large Renal Artery Aneurysm and Associated Arteriovenous Fistula Gustavo Torres, MD, Thomas T. Terramani, MD, and Fred A. Weaver, MD, Los Angeles, California
The development of a renal artery to vein arteriovenous fistula due to a large extraparenchymal renal artery aneurysm is uncommon. Previous surgical experience with this entity is limited. Based on the existing surgical literature, nephrectomy has been the treatment of choice. We report preservation of the kidney by surgical correction of this entity using ex vivo "bench" repair in a middle-aged female with fibromuscular dysplasia of the renal artery. The technique, results, and recommendations for surgical management are discussed.
INTRODUCTION Fibromuscular dysplasia (FMD) of the renal arteries is a leading cause of renovascular hypertension. FMD most c o m m o n l y affects w o m e n ages 35-55 and includes a variety of hyperplastic and fibrosing lesions of the intima, media, a n d / o r adventitia. Medial fibrodysplasia is the most c o m m o n type, and is present in approximately 85% of patients with FMD of the renal artery. Angiographically it is likened to a string of beads that involves the mid- to distal main renal artery with extension to the firstorder segmental branch vessels in approximately 25% of patients. 1 The association of renal artery aneurysms with medial fibrodysplasia FMD is well
Department of Surgery, Division of Vascular Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA. Presented at the Annual Meeting of the Southern California Vascular Surgical Society, Santa Barbara, CA, April 27-29, 2001. Correspondence to: F.A. Weaver, MD, USC School of Medicine, 1510 San Pablo Avenue, Suite 514, Los Angeles, CA 90033-4612, USA. Phone: 323-442-5907, Fax: 323-442-5735 E-mail: [email protected]. Ann Vasc Surg 2002; ld: 141-144 DO[: lO.IO07/slOO16-OOl-O155-z 9 Annals of Vascular Surgery Inc. Published online: February 13, 2002
recognized. However, it is u n c o m m o n , even with large renal artery aneurysms that erosion and fistulization into the adjacent renal vein occurs. This report describes a patient with a giant renal artery a n e u r y s m associated with medial fibrodysplasia complicated by high-outflow fistula into the right renal vein. The patient was treated successfully with preservation of the kidney by orthotopic ex vivo vascular reconstruction. CASE REPORT A 61-year-old female was found on routine urinalysis to have microscopic hematuria. Her past medical history was significant for hypertension for 20 years, mitral valve prolapse, atrial tachyarrhythmias, and mild congestive heart failure (CHF) manifested by two-pillow orthopnea. Her medications included Zestril, Atenolol, and Prinivil. To evaluate the hematuria she u n d e r w e n t an abdominal c o m p u t e r t o m o g r a p h y (CT) scan, which demonstrated a large right renal artery a n e u r y s m and enlarged right renal vein. This prompted an abdominal aortogram, which showed a large saccular right renal artery a n e u r y s m measuring 3.2 cm located in the renal hilum, an arteriovenous fistula
141
142
Torres et al.
Fig. 1. Angiogram demonstrating large right renal artery with dysplastic changes and a large saccular aneurysm. from the a n e u r y s m to the right renal vein, and an 8-turn right renal artery with a beaded, corrugated appearance consistent with medial fibrodysplasia (Figs. 1 and 2). The left renal artery was normal in size and w i t h o u t evidence of FMD. She was then referred to University of Southern California (USC) University Hospital for further evaluation and treatment. At initial evaluation her blood pressure was 190/90; she was in n o r m a l sinus r h y t h m with a II/VI cardiac systolic ejection m u r m u r . A pulsatile right-sided abdominal mass was evident and associated with a machine-like c o n t i n u o u s abdominal bruit. Trace-pitting pretibial edema was observed in both lower extremities. Laboratory data indicated n o r m a l renal function with a blood urea nitrogen (BUN) of 19 and creatinine of 0.9. The patient u n d e r w e n t operative repair t h r o u g h a midline transabdominal approach. Intraoperatively the right renal vein was f o u n d to be dilated to approximately 2.5 times normal caliber. The aneurysm was calcified and appeared to arise from the upper pole first-order segmental branch. The repair of the renal artery was performed using an ex vivo approach that has been previously described. 2 The kidney p a r e n c h y m a was freed from the s u r r o u n d -
Annals o[ Vascular Surgery
Fig. 2. Later phase of angiogram documenting fistulous connection with right renal vein and early visulization of inferior vena cava. ing Gerota's fascia and mobilized on the renal artery and vein pedicle. The origin of the renal artery was identified and the artery was traced u n d e r the cava to the renal hilum. Lumbar branches to the vena cava were ligated to provide access to the renal artery as it coursed posterior to the inferior vena cava. The ureter was mobilized to the pelvic brim, taking care to preserve the periureteral vesssels. Following intravenous administration of heparin, the renal artery at its origin was clamped, oversewn, and divided. A side-biting clamp was placed on the vena cava at the renal vein origin and the vein was divided by taking a small cuff of vena cava. The kidney was lifted from the renal fossa, an atraumatic clamp was applied to the ureter to p r e v e n t renal w a r m i n g from ureteral vessels, and the kidney was flushed t h r o u g h the renal artery with a cold (4~ modified Collins solution until the venous effluent was clear and the p a r e n c h y m a pale. It was placed in a plastic bag and cooled externally with cold laparotomy packs. The a n e u r y s m was opened and the fistulous c o n n e c t i o n to a large upper pole branch of the renal vein was identified. The renal branch was severed from the a n u e r y s m and ligated. The
Vo]. 16, No. 2, 2 0 0 2
a n e u r y s m originated at the branch point of the u p p e r and middle first-order segmental branches. After resection of the a n e u r y s m and proximal dilated m a i n renal artery, a c o m m o n cuff of the two b r a n c h e s was created by suturing the medial walls of the branches together using 7-0 Prolene suture. A s e g m e n t of reverse greater s a p h e n o u s vein, h a r v e s t e d from the thigh, was sutured to the c o m m o n cuff containing the u p p e r a n d mid-segm e n t a l branches. The lower pole b r a n c h was attached to the side of the vein graft at a separate location. The kidney was placed back in its anatomic position, the arterial graft was placed posterior to the v e n a cava, and an end-to-side anastomosis to the infrarenal a b d o m i n a l aorta was performed. The renal vein was reattached to the v e n a cava. The arterial and v e n o u s clamps were released simultaneously a n d the renal p a r e n c h y m a was reperfnsed. Intraoperative duplex e x a m docum e n t e d a satisfactory repair with n o r m a l velocity profiles in the m a i n renal artery a n d vein. Gerotas fascia was closed over the kidney to p r e v e n t torsion. The patient had an u n e v e n t f u l postoperative course; she was discharged on postoperative day 6. At follow-up of 8 m o n t h s her blood pressure was 125/80 on Atenolol only. Renal function (BUN - 8 and creatinine - 0.7) was n o r m a l a n d a renal artery duplex scan s h o w e d a right kidney i0 cm in length with n o r m a l velocity profiles in the right renal artery and vein. She no longer complained of shortness of breath w h e n supine.
DISCUSSION A l t h o u g h FMD of the renal arteries is an u n c o m m o n condition, it is the s e c o n d - m o s t c o m m o n cause of correctable renovascnlar h y p e r t e n s i o n in the United States, accounting for 18-40% of cases. 3 The right renal artery is m o r e c o m m o n l y affected t h a n the left, but bilateral i n v o l v e m e n t is present in the vast majority of patients. The classical FMD finding of "string of beads" usually involves the m i d - m a i n renal artery but can e x t e n d into the segmental branches on occasion. Small and, on occasion, large renal artery a n e u r y s m s are associated with the medial fibrodysplasia type of FMD. However, fistulization to the adjacent renal vein is rarely reported, with only three cases having b e e n d o c u m e n t e d in the English literature. The rarity of fistula f o r m a t i o n is s o m e w h a t surprising, given the proximity of the renal vein and the possibility of vein branches being stretched tautly o v e r the surface of a large a n e u r y s m . 4
Ex vivo repair of re~al arte W aneut3'sm
143
Although renal artery a n e u r y s m s are most c o m m o n l y associated with EMD, they can also occur following renal artery dissection, renal artery t r a u m a , or in association with m e d i u m - s i z e d vessel arteritis. Large, solitary a n e u r y s m s occur less frequently and are most likely congenital. Approximately 90% of renal artery a n e u r y s m s are e x t r a p a r e n c h y m a l and saccular in configuration. Most are a s y m p t o m a t i c at the time of diagnosis. The most c o m m o n complication is rupture. Risk factors for rupture include p r e g n a n c y and hypertension. Indications for operation include s y m p t o m a t i c patients with a ruptured or leaking a n e u r y s m , ane u r y s m s suspected of causing renovascular hypertension, and expansion of an a n e u r y s m or renal p a r e n c h y m a l embolization. For a s y m p t o m a t i c aneurysms discovered incidentally, size determines the need for intervention, with most authors reco m m e n d i n g surgery for a n e u r y s m s >1.5-2.5 cm in diameter. 4,5 There are only three reports in the literature concerning the surgical m a n a g e m e n t of a large e x t r a p a r e n c h y m a l renal artery a n e u r y s m that has fistulized to the renal vein. Two cases presented with acute i n t r a a b d o m i n a l h e m o r r h a g e requiring i m m e d i a t e operation and one case was diagnosed a n d treated electively. Similar to our patient, all three patients at diagnosis had evidence of a central h i g h - o u t p u t arteriovenous f i s t u l a - - n a m e l y diastolic hypertension, a m a c h i n e - l i k e c o n t i n u o u s abdominal bruit, and heart failure. 6-9 The three patients were treated with n e p h r e c t o m y , but these reports were before the t e c h n i q u e of ex vivo reconstruction was refined. In 1975, Belzer et al. described five patients in w h o m the t e c h n i q u e of ex vivo reconstruction was used to surgically treat r e n o v a s c u l a r h y p e r t e n s i o n due to complex branch disease of the renal artery, l~ The advantages of such an a p p r o a c h were optimal vascular exposure in a bloodless surgical field and renal protection from prolonged w a r m ischemia. By establishing renal h y p o t h e r m i a t h r o u g h external renal cooling and flushing of the p a r e n c h y m a with Ringer's lactate at 4~ Belzer was able to minimize renal metabolic d e m a n d . This preserved renal p a r e n c h y m a and function and provided the time needed to reconstruct renal b r a n c h vessels 1 to 3 m m in diameter. Following vascular reconstruction, he placed the reconstructed kidney in the pelvis with arterial and v e n o u s anastomoses to the c o m m o n iliac or hypogastric artery and vein. For renal transplant surgeons such as Belzer, the advantages of the heterotopic position of the kidney included easy
144
Annals of Vascular Surgery
Tortes et al.
m a n u a l p a l p a t i o n of t h e k i d n e y , easy access for biopsy, use of t h e h y p o g a s t r i c a r t e r y for i n f l o w , a n d ease of r e m o v a l for t r a n s p l a n t r e j e c t i o n , H o w e v e r , in the n o n t r a n s p l a n t p a t i e n t , n o n e of these adv a n t a g e s are o p e r a t i v e . Since t h e k i d n e y c a n be q u i t e easily p l a c e d i n its u s u a l a n a t o m i c location, w i t h the a d d e d b e n e f i t of e l i m i n a t i n g t h e pelvic dissection r e q u i r e d to expose t h e c o m m o n iliac or h y p o g a s t r i c a r t e r y a n d iliac v e i n , D e a n et al. m o d ified Belzer's ex v i v o t e c h n i q u e a n d placed t h e reconstructed k i d n e y in an orthotopic position, a technique that we have adopted with only minor m o d i f i c a t i o n . ~1 Despite t h e s e e m i n g c o m p l e x i t y of ex vivo vascular reconstruction, postoperative complications are r e p o r t e d l y f e w a n d p a t e n c y of t h e r e c o n s t r u c t e d r e n a l a r t e r y a p p r o a c h e s 1 0 0 % . 2'11 O u r p r e v i o u s e x p e r i e n c e w i t h ex vivo r e c o n s t r u c t i o n for a v a r i e t y of r e n a l a r t e r y lesions suggested t h a t it w o u l d e n able v a s c u l a r i s o l a t i o n a n d r e p a i r of o u r p a t i e n t ' s r e n a l a r t e r y to v e i n fistula w i t h m i n i m a l b l o o d loss, renal dysfunction, and morbidity. This is t h e first r e p o r t of a large e x t r a p a r e n c h y m a l saccular r e n a l a r t e r y a n e u r y s m c o m p l i c a t e d b y f i s t u l i z a t i o n to t h e r e n a l v e i n w h i c h was r e p a i r e d u s i n g ex vivo r e c o n s t r u c t i v e t e c h n i q u e s . A l t h o u g h n e p h r e c t o m y is a n a c c e p t a b l e o p t i o n i n the elective setting, ex vivo repair is preferred, since it allows for salvage of r e n a l p a r e n c h y m a w i t h a h i g h d e g r e e of reliability. C o n s e q u e n t l y , n e p h r e c t o m y s h o u l d be r e s e r v e d for p a t i e n t s w h o p r e s e n t i n e x t r e m i s d u e to t h e c a r d i o v a s c u l a r c o m p l i c a t i o n s of t h e
fistula or h e m o r r h a g e f r o m a l e a k i n g r e n a l a r t e r y aneurysm.
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