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Abdominal Aortic Aneurysm Associated With Horseshoe Kidney and Duplication of the Inferior Vena Cava
Abdominal Aortic Aneurysm Associated With Horseshoe Kidney and Duplication of the Inferior Vena Cava Pierre Julia, MD, Marie-Christine Hanotel, MD, Balkis GhatayinL MD, and Jean-Noel FabianL MD, Paris, France
A patient with an abdominal aortic aneurysm associated with horseshoe kidney and duplication of the inferior vena cava is described. Of all the preoperative investigations, CT scan was the most accurate. Operative difficulties stemmed essentially from the abnormal origin of the renal arteries and the functional anatomy of the horseshoe kidney. An anterior approach, as opposed to the posterior approach, allowed easy access to the aneurysmal neck despite the presence of a duplicated inferior vena cava. (Ann Vasc Surg 1993;7:587-589.)
The presence of either renal or v e n o u s a b n o r m a l ities of embryologic origin can h i n d e r surgical access to the a b d o m i n a l aorta. A l t h o u g h the h o r s e s h o e k i d n e y is one of the m o s t frequent renal embryologic abnormalities, its association w i t h a n a b d o m i n a l aortic a n e u r y s m (AAA) is rare, w i t h a n e s t i m a t e d incidence of 0.5% to 0.8%.' Duplication of the inferior vena cava (IVC) is seen in 0.5% to 3% of the p o p u l a t i o n 2 a n d failure to recognize this a b n o r m a l i t y c a n lead to disastrous v e n o u s injuries) To the best of our k n o w l e d g e the association of these t w o a n o m a l i e s w i t h a n AAA has n o t been reported previously. We report a case a n d describe the technical difficulties related to t r e a t m e n t .
CASE REPORT A 58-year-old man was admitted to our hospital in March 1992 for treatment of aneurysms of the abdominal aorta and right common iliac artery. He had a history of coronary artery disease that required a dou-
From the Service de Chirurgie Cardiovasculaire, Hopital Broussais, Paris, France. Reprint requests: Jean-Noel Fabiani, MD, Service de Chirurgie Cardiovasculaire, Hopital Broussais, 96 rue Didot, 75014 Paris, France.
ble coronary artery bypass in February 1990. In November 1989, prior to myocardial revascularization, abdominal sonograms had revealed the presence of an AAA. A follow-up CT scan performed in March 1992 (Fig. 1) showed that the aneurysm had increased in size, measuring 5 cm at the level of the aorta and 4 cm at the level of the right fliac artery. Moreover, the CT scan showed a horseshoe kidney and a duplicated IVC. Preoperative arteriograms (Fig. 2) showed that the AAA was infrarenal and the iliac extension limited to the right common iliac artery. The distal arterial runoff was satisfactory. On the other hand, as selective films were not obtained, no information was available regarding polar vessels or arteries feeding the isthmus of the kidney. Through a midline xiphoid to pubis incision, control of the aneurysmal neck was obtained distal to the left renal vein (LRV) at the level of its confluence with the left inferior vena cava (LWC)~ The LIVC was mobilized without difficulty and no division was required. The origin of the left common iliac artery and the bifurcation of the right common fliac artery were dissected free. The isthmus of the horseshoe kidney, which was vascularized by two arteries originating from a common trunk arising from the anterior aspect of the aneurysm, was ligated and divided. A 20/10 albumincoated prosthetic graft was inserted between the infrarenal aorta and the origin of the left common iliac artery and the right common femoral artery, excluding the right iliac artery aneurysm. The common trunk of the isthmic arteries, retrieved with a button of aortic 587
588
Annals of Vascular Surgery
Julia et al.
Fig. 1. CT scan showing the abdominal aneurysm, the isthmus of the kidney in front of it, and the duplicated IVC.
DISCUSSION
Fig. 2. Arteriogram showing the right aortoiliac aneurysm. Note the abnormal location of the urinary collecting system.
tissue, was reimplanted on the anterior aspect of the graft. The postoperative course was uneventful and there were no signs of infection or urinary tract leak. The patient was discharged on day 8. At 3 months the patient was asymptomatic. Duplex scanning demonstrated patency of the graft and the patient had no urologic manifestations.
A h o r s e s h o e k i d n e y associated w i t h an AAA is rare. A preoperative diagnosis can usually be m a d e by CT scan. 4 According to the literature, however, in 25% of cases the diagnosis is m a d e intraoperatively. Arteriograms are essential to delineate the origins of the m a i n renal and isthmic arteries. Major difficulties arise w h e n a substantial part of the kidneys is vascularized by arteries arising f r o m the a n e u r y s m , particularly w h e n renal artery anomalies are associated. 5 The incid e n c e of such renal artery anomalies can be as high as 60% to 80%. 6 The k i d n e y isthmus, w h i c h is generally located o n the anterior aspect of the a n e u r y s m , poses the second problem. Suture ligation of the i s t h m u s is usually n e e d e d to gain access to the a n e u r y s m , ~'7 but despite the attend a n t risk o f postoperative urinary tract leak a n d / o r infection, severe complications are exceptional. However, w h e n the i s t h m u s is thick, functional, a n d heavily vascularized, it m a y be preferable to t u n n e l the prosthesis b e h i n d it. Those w h o advocate the posterolateral retroperitoneal app r o a c h for this surgery claim two advantages: ( 1 ) the a n e u r y s m can potentially be o p e n e d in its posterolateral aspect and therefore the arteries r e i m p l a n t e d to vascularize the kidneys transane u r y s m a l l y and (2) the i s t h m u s can potentially be retracted anteriorly w i t h o u t having to divide i t . 4'6'7 These p r o p o n e n t s reserve the anterior transperitoneal a p p r o a c h for renal revascularization w h e n the two m a i n renal arteries arise above the aneur y s m or w h e n the i s t h m u s is located b e h i n d the a n e u r y s m , a rare finding. 6 We preferred to use an
Vol. 7, No. 6 1993
anterior approach because of the presence of an associated large aneurysm of the right common iliac artery. The postoperative course after suture division of the kidney isthmus was uneventful. Moreover, the anterior approach allowed control of the aneurysmal neck distal to the left renal artery without being hindered by the presence of the LIVC. This would not be possible through a retroperitoneal approach. LIVC and duplication of the IVC m'n are the most commonly encountered anomalies of the IVC. According to autopsy series, duplication of the IVC seems to be found more frequently than LIVC: 1.5% to 3% vs 0.2% to 0 . 4 5 % . 2'3'8 When these anomalies are not recognized preoperatively, they can be responsible for potentially severe bleeding complications, particularly in the case of ruptured aneurysm repair. 9 However, even during the course of elective surgery, the presence of posterior retroaortic venous branches can be a hazard during attempts to control the aorta. A preoperative CT scan can detail venous anomalies, including IVC duplication as well as a left duplicated or retroaortic renal vein. ~2 Technical difficulties related to WC duplication are essentially encountered at the level of the aneurysmal neck, which is usually crossed anteriorly and obliquely by the junction of the LRV and LIVC. When clamping is not possible after simple dissection, the LRV or the infrarenal portion of the LIVC may be divided and reconstructed. In our case the aneurysmal neck was accessible after simple dissection. In one case reported in the literature an AAA was approached retroperitoneally in the presence of an LIVC.'3 The d{agnosis had not been made on a preoperative CT scan. The neck of the aneurysm was accessible only after the LIVC was fully mobilized b y division of several lumbar veins.
CONCLUSION To the best of our knowledge the association of horseshoe kidney and duplicated vena cava with an AAA has not been previously described. These
AAA with horseshoe kidney and duplication of lVC
589
embryologic anomalies arise between the fourth and eighth ~4 and fifth and seventh weeks of fetal life, respectively. Preoperative detection by CT scan is paramount to reduce the risk of venous injury and to choose the most appropriate surgical approach. In the case presented the operation was performed through an anterior approach without any intra- or postoperative complications. This seems to be the preferred route in the event of associated IVC anomalies. REFERENCES 1. Cayten CG, Davis AV, Berkowitz HD, et at. Ruptured abdominal aortic a n e u r y s m s in the presence of horseshoe kidneys. Surg Gynecol Obstet 1972;135:945-949. 2. Lindblad L. Duplicated inferior vena cava in a patient with an abdominal aortic a n e u r y s m . A n n Chir Gynecol 1978;67:3032. 3. Battle EJ, Pearce WH, Sun JH, et al. Infrarenal venous anomalies and aortic surgery: Avoiding vascular injury. d Vasc Surg 1987;6:590-593. 4. Crawford ES, Coselli JS, Sail HJ, et al. The impact of renal fusion a n d ectopia on aortic surgery, d Vasc Surg 1988;8:375383. 5. Van D a m m e H, Garcez JL, Dereume JP. An~vrysme de l'aorte abdominale et rein en fer h chevaL J Mal Vasc 1987;12:241245. 6. Morin JF, J o h n s t o n KW. Thoracoabdominal retroperitoneal approach for repair of a b d o m i n a l aortic a n e u r y s m associated with horseshoe kidney. A n n Vasc Surg 1988;2:82-84. 7. Lesage R, Vignes B, Bahnini A, et al. An6vrysmes de l'aorte abdominale et anomalies r6nales cong6nitales. In Kieffer E, ed. Les An6vrysmes de l'Aorte Abdominale Sous-r6nale. Paris: AERCV, 1990, pp 319-335. 8. Mayo J, Gray R, St. Louis E, et al. Anomalie of the inferior vena cava, AJR 1983;140:339-345. 9. De Laurentis DA, Calligaro KD, Savarese RP, Anomalies veineuses compliquant la chirurgie des an6vrysmes de l'aorte abdominale. In Kieffer E, ed. Les An6~Tysmes de l'Aorte Abdominale Sous-r6nale. Paris: AERCV, 1990, pp 287-294. 10. Strange-Vognsen HH, Lindewald H, B r o - R a s m u s s e n E et al. A n o m a l o u s vena cava impeding implantation of aortobifemoral vascular prosthesis. J Cardiovasc Surg 1988;29:488-490. l l . Hans SS, Gordon M. Double inferior vena cava a n d abdominal aortic a n e u r y s m . J Cardiovasc Surg 1985;26:76-78. 12. Giordano JM, Trout HH, Anomalies of the inferior vena cava. J Vasc Surg 1986;3:924-928. 13. Perler BA. Abdominal aortic replacement with a left-sided inferior vena cava: Transperitoneal a n d retroperitoneal approaches. J Cardiovasc Surg 1989;30:236-240. 14. Glen JF. Analysis of 51 patients with horseshoe kidney. N Engl J Med 1959;261:684-687.
A patient with an abdominal aortic aneurysm associated with horseshoe kidney and duplication of the inferior vena cava is described. Of all the preoperative investigations, CT scan was the most accurate. Operative difficulties stemmed essentially from the abnormal origin of the renal arteries and the functional anatomy of the horseshoe kidney. An anterior approach, as opposed to the posterior approach, allowed easy access to the aneurysmal neck despite the presence of a duplicated inferior vena cava. (Ann Vasc Surg 1993;7:587-589.)
The presence of either renal or v e n o u s a b n o r m a l ities of embryologic origin can h i n d e r surgical access to the a b d o m i n a l aorta. A l t h o u g h the h o r s e s h o e k i d n e y is one of the m o s t frequent renal embryologic abnormalities, its association w i t h a n a b d o m i n a l aortic a n e u r y s m (AAA) is rare, w i t h a n e s t i m a t e d incidence of 0.5% to 0.8%.' Duplication of the inferior vena cava (IVC) is seen in 0.5% to 3% of the p o p u l a t i o n 2 a n d failure to recognize this a b n o r m a l i t y c a n lead to disastrous v e n o u s injuries) To the best of our k n o w l e d g e the association of these t w o a n o m a l i e s w i t h a n AAA has n o t been reported previously. We report a case a n d describe the technical difficulties related to t r e a t m e n t .
CASE REPORT A 58-year-old man was admitted to our hospital in March 1992 for treatment of aneurysms of the abdominal aorta and right common iliac artery. He had a history of coronary artery disease that required a dou-
From the Service de Chirurgie Cardiovasculaire, Hopital Broussais, Paris, France. Reprint requests: Jean-Noel Fabiani, MD, Service de Chirurgie Cardiovasculaire, Hopital Broussais, 96 rue Didot, 75014 Paris, France.
ble coronary artery bypass in February 1990. In November 1989, prior to myocardial revascularization, abdominal sonograms had revealed the presence of an AAA. A follow-up CT scan performed in March 1992 (Fig. 1) showed that the aneurysm had increased in size, measuring 5 cm at the level of the aorta and 4 cm at the level of the right fliac artery. Moreover, the CT scan showed a horseshoe kidney and a duplicated IVC. Preoperative arteriograms (Fig. 2) showed that the AAA was infrarenal and the iliac extension limited to the right common iliac artery. The distal arterial runoff was satisfactory. On the other hand, as selective films were not obtained, no information was available regarding polar vessels or arteries feeding the isthmus of the kidney. Through a midline xiphoid to pubis incision, control of the aneurysmal neck was obtained distal to the left renal vein (LRV) at the level of its confluence with the left inferior vena cava (LWC)~ The LIVC was mobilized without difficulty and no division was required. The origin of the left common iliac artery and the bifurcation of the right common fliac artery were dissected free. The isthmus of the horseshoe kidney, which was vascularized by two arteries originating from a common trunk arising from the anterior aspect of the aneurysm, was ligated and divided. A 20/10 albumincoated prosthetic graft was inserted between the infrarenal aorta and the origin of the left common iliac artery and the right common femoral artery, excluding the right iliac artery aneurysm. The common trunk of the isthmic arteries, retrieved with a button of aortic 587
588
Annals of Vascular Surgery
Julia et al.
Fig. 1. CT scan showing the abdominal aneurysm, the isthmus of the kidney in front of it, and the duplicated IVC.
DISCUSSION
Fig. 2. Arteriogram showing the right aortoiliac aneurysm. Note the abnormal location of the urinary collecting system.
tissue, was reimplanted on the anterior aspect of the graft. The postoperative course was uneventful and there were no signs of infection or urinary tract leak. The patient was discharged on day 8. At 3 months the patient was asymptomatic. Duplex scanning demonstrated patency of the graft and the patient had no urologic manifestations.
A h o r s e s h o e k i d n e y associated w i t h an AAA is rare. A preoperative diagnosis can usually be m a d e by CT scan. 4 According to the literature, however, in 25% of cases the diagnosis is m a d e intraoperatively. Arteriograms are essential to delineate the origins of the m a i n renal and isthmic arteries. Major difficulties arise w h e n a substantial part of the kidneys is vascularized by arteries arising f r o m the a n e u r y s m , particularly w h e n renal artery anomalies are associated. 5 The incid e n c e of such renal artery anomalies can be as high as 60% to 80%. 6 The k i d n e y isthmus, w h i c h is generally located o n the anterior aspect of the a n e u r y s m , poses the second problem. Suture ligation of the i s t h m u s is usually n e e d e d to gain access to the a n e u r y s m , ~'7 but despite the attend a n t risk o f postoperative urinary tract leak a n d / o r infection, severe complications are exceptional. However, w h e n the i s t h m u s is thick, functional, a n d heavily vascularized, it m a y be preferable to t u n n e l the prosthesis b e h i n d it. Those w h o advocate the posterolateral retroperitoneal app r o a c h for this surgery claim two advantages: ( 1 ) the a n e u r y s m can potentially be o p e n e d in its posterolateral aspect and therefore the arteries r e i m p l a n t e d to vascularize the kidneys transane u r y s m a l l y and (2) the i s t h m u s can potentially be retracted anteriorly w i t h o u t having to divide i t . 4'6'7 These p r o p o n e n t s reserve the anterior transperitoneal a p p r o a c h for renal revascularization w h e n the two m a i n renal arteries arise above the aneur y s m or w h e n the i s t h m u s is located b e h i n d the a n e u r y s m , a rare finding. 6 We preferred to use an
Vol. 7, No. 6 1993
anterior approach because of the presence of an associated large aneurysm of the right common iliac artery. The postoperative course after suture division of the kidney isthmus was uneventful. Moreover, the anterior approach allowed control of the aneurysmal neck distal to the left renal artery without being hindered by the presence of the LIVC. This would not be possible through a retroperitoneal approach. LIVC and duplication of the IVC m'n are the most commonly encountered anomalies of the IVC. According to autopsy series, duplication of the IVC seems to be found more frequently than LIVC: 1.5% to 3% vs 0.2% to 0 . 4 5 % . 2'3'8 When these anomalies are not recognized preoperatively, they can be responsible for potentially severe bleeding complications, particularly in the case of ruptured aneurysm repair. 9 However, even during the course of elective surgery, the presence of posterior retroaortic venous branches can be a hazard during attempts to control the aorta. A preoperative CT scan can detail venous anomalies, including IVC duplication as well as a left duplicated or retroaortic renal vein. ~2 Technical difficulties related to WC duplication are essentially encountered at the level of the aneurysmal neck, which is usually crossed anteriorly and obliquely by the junction of the LRV and LIVC. When clamping is not possible after simple dissection, the LRV or the infrarenal portion of the LIVC may be divided and reconstructed. In our case the aneurysmal neck was accessible after simple dissection. In one case reported in the literature an AAA was approached retroperitoneally in the presence of an LIVC.'3 The d{agnosis had not been made on a preoperative CT scan. The neck of the aneurysm was accessible only after the LIVC was fully mobilized b y division of several lumbar veins.
CONCLUSION To the best of our knowledge the association of horseshoe kidney and duplicated vena cava with an AAA has not been previously described. These
AAA with horseshoe kidney and duplication of lVC
589
embryologic anomalies arise between the fourth and eighth ~4 and fifth and seventh weeks of fetal life, respectively. Preoperative detection by CT scan is paramount to reduce the risk of venous injury and to choose the most appropriate surgical approach. In the case presented the operation was performed through an anterior approach without any intra- or postoperative complications. This seems to be the preferred route in the event of associated IVC anomalies. REFERENCES 1. Cayten CG, Davis AV, Berkowitz HD, et at. Ruptured abdominal aortic a n e u r y s m s in the presence of horseshoe kidneys. Surg Gynecol Obstet 1972;135:945-949. 2. Lindblad L. Duplicated inferior vena cava in a patient with an abdominal aortic a n e u r y s m . A n n Chir Gynecol 1978;67:3032. 3. Battle EJ, Pearce WH, Sun JH, et al. Infrarenal venous anomalies and aortic surgery: Avoiding vascular injury. d Vasc Surg 1987;6:590-593. 4. Crawford ES, Coselli JS, Sail HJ, et al. The impact of renal fusion a n d ectopia on aortic surgery, d Vasc Surg 1988;8:375383. 5. Van D a m m e H, Garcez JL, Dereume JP. An~vrysme de l'aorte abdominale et rein en fer h chevaL J Mal Vasc 1987;12:241245. 6. Morin JF, J o h n s t o n KW. Thoracoabdominal retroperitoneal approach for repair of a b d o m i n a l aortic a n e u r y s m associated with horseshoe kidney. A n n Vasc Surg 1988;2:82-84. 7. Lesage R, Vignes B, Bahnini A, et al. An6vrysmes de l'aorte abdominale et anomalies r6nales cong6nitales. In Kieffer E, ed. Les An6vrysmes de l'Aorte Abdominale Sous-r6nale. Paris: AERCV, 1990, pp 319-335. 8. Mayo J, Gray R, St. Louis E, et al. Anomalie of the inferior vena cava, AJR 1983;140:339-345. 9. De Laurentis DA, Calligaro KD, Savarese RP, Anomalies veineuses compliquant la chirurgie des an6vrysmes de l'aorte abdominale. In Kieffer E, ed. Les An6~Tysmes de l'Aorte Abdominale Sous-r6nale. Paris: AERCV, 1990, pp 287-294. 10. Strange-Vognsen HH, Lindewald H, B r o - R a s m u s s e n E et al. A n o m a l o u s vena cava impeding implantation of aortobifemoral vascular prosthesis. J Cardiovasc Surg 1988;29:488-490. l l . Hans SS, Gordon M. Double inferior vena cava a n d abdominal aortic a n e u r y s m . J Cardiovasc Surg 1985;26:76-78. 12. Giordano JM, Trout HH, Anomalies of the inferior vena cava. J Vasc Surg 1986;3:924-928. 13. Perler BA. Abdominal aortic replacement with a left-sided inferior vena cava: Transperitoneal a n d retroperitoneal approaches. J Cardiovasc Surg 1989;30:236-240. 14. Glen JF. Analysis of 51 patients with horseshoe kidney. N Engl J Med 1959;261:684-687.