Intra-operative central vein angioplasty during arteriovenous access creation
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《血管的通路杂志》
1.Department of Surgery and Vascular Surgery Unit, Shaare Zedek Medical Center (Affiliated with the Faculty of Health Sciences, Ben-Gurion University of the Negev), Jerusalem - Israel
2.Invasive Radiology Unit, Shaare Zedek Medical Center (Affiliated with the Faculty of Health Sciences, Ben-Gurion University of the Negev), Jerusalem - Israel
3.Anesthesiology Department Shaare Zedek Medical Center (Affiliated with the Faculty of Health Sciences, Ben-Gurion University of the Negev), Jerusalem - Israel
ABSTRACT
Central vein stenosis or occlusion due to prior use of central vein hemodialysis catheters may lead to disabling extremity edema or cause early failure after arteriovenous access construction. Our integrated program for arteriovenous access management enables us to identify these stenoses pre-operatively. We carried out
intra-operative angiography and angioplasty during arteriovenous access creation in 3 patients with good immediate and long-term results. Intra-operative endovascular therapy is a new application of peripheral vascular surgery techniques for patients with significant central vein stenosis undergoing access surgery, which exploits the high postoperative flow state to maintain patency after angioplasty. It may also be applicable in situations such as proximal arterial stenosis with anticipated steal syndrome and other conditions that may compromise access patency.
Key Words: Renal dialysis, Surgical arteriovenous shunt, Ultrasonography, Doppler, Duplex, Angioplasty
INTRODUCTION
Many patients with end stage renal disease will require hemodialysis for a prolonged period. Careful preoperative venous and arterial mapping and
planning of the access procedure have minimized failure rates in the setting of a vascular access center (1, 2), utilizing color-coded duplex ultrasonography
(DUS) performed by the surgeon himself. Areas of stenosis and previous inflammation are taken into account in planning the fistula, and the best veins are selected by the surgeon. The arterial tree is also examined carefully in both arms to determine the suitability of the arteries for access creation and the risk of steal syndrome. Patients previously dialyzed via central vein catheters for prolonged periods or those with pacemakers should undergo preoperative venography (3-5). In patients with central vein occlusion or severe stenosis there is a high risk of access failure (6). If the access does not occlude, severe edema may result causing pain and delaying the start of dialysis via the access until postoperative angioplasty is performed. To prevent these potential complications we decided to combine the access surgery with intra-operative endovascular therapy, utilizing the high flow in the access to maintain patency. We describe the technique of central vein transluminal angioplasty carried out intra-operatively during surgery for autogenous arteriovenous access (AVA) construction in 3 patients.
DETAILS OF THE PROCEDURE
Preoperative imaging
All patients were examined preoperatively for planning the AVA according to our protocol (1, 2). DUS was performed by the access surgeon using an Acuson Sequoia 512 (Mountain View, CA, USA) with a 6L3 multifrequency linear array transducer. Preoperative venography was carried out on those patients who required further investigation for central venous stenosis as outlined above. Digital subtraction venography was performed (Siemens Polystar, Siemens, Erlangen, Germany) utilizing concurrent injections from both upper limbs during a single breath hold. Approximately 20 cc. of iopamidol low-osmolar contrast (Iopamiro 370, Bracco s.p.a. Milan, Italy) was injected utilizing veins previously mapped during DUS wherever possible. Normal saline flush and intravenous catheter removal were carried out immediately following the procedure.
Surgical technique
In all cases surgery took place under regional brachial plexus block. Exposure and anastomosis were carried out according to the pre-operative DUS findings. The end to side anastomosis between the cephalic or transposed basilic vein and the brachial artery was completed with preservation of
the intermediate cubital vein and basilic vein branches in all the patients. This enabled insertion of a 7 French introducer sheath through a side
branch after completion of the anastomosis and removal of the clamps, in the setting of a high flow state (Fig. 1).
Intraoperative endovascular procedure
Preliminary digital subtraction angiography was performed (OEC 9800 C-Arm, GE-OEC, Salt Lake City, Utah USA) to locate the previously identified central stenosis. A Berenstein Catheter (Angiodynamics Inc. Queensbury, New York, USA) and Nimble Roadrunner hydrophilic guidewire (Cook Inc. Bloomington, Indiana, USA) were passed through the lesion and angioplasty was performed using a Workhorse II balloon catheter (Angiodynamics Inc. Queensbury, New York, USA). This was followed by completion angiography, removal of the sheath and ligation of the side branch.
Postoperative follow-up
Sutures were removed 10 days postoperatively and patients were examined at 6 weeks by DUS. Hemodialysis was begun using the best available venipuncture sites selected according to the DUS findings and marked for the nephrology team (7). Planned angiography was repeated at 2 months with the aim of examining the treated region of the central vein and carrying out further endovascular treatment if necessary.
CLINICAL EXPERIENCE
Three patients with severe proximal central vein stenosis on pre-operative ascending venography were scheduled for upper arm autogenous AVA construction combined with intra-operative angioplasty (Tab. I).
Patient 1: Preoperative venography showed complete occlusion of the left subclavian and innominate veins precluding the use of that upper extremity
for access. On the right side DUS demonstrated a cephalic vein suitable for autogenous AVA but there was a severe stenosis of the subclavian vein on venography and surgery with operative angioplasty on the right was planned. Before the patient reached surgery a internal jugular catheter was inserted on the right for hemodialysis. A reasonable result was obtained on intraoperative angioplasty with a 40% residual stenosis in the right subclavian vein. The presence of a central venous catheter on the right side, where the new access was constructed, prevented further angioplasty, which was deferred until the access matured. Dialysis through the new access was begun 6 weeks after its
creation and the central venous catheter was removed. The planned post-operative angiography at 2 months showed the subclavian vein to be patent,
and the residual stenosis was angioplastied again. She had a kidney transplant 7 months later and gradually developed significant arm edema over until she died of stroke 6 months after the transplant. Further angioplasty was not carried out because of her precarious medical state. Patient 2: Preoperative ascending venography showed significant stenosis in the left subclavian vein where pacemaker wires entered the vein and significant stenosis at the confluence of the right subclavian and innominate veins (Fig. 2).
Patient 2 preoperative venography. Left ascending venography
with permanent pacemaker. There is a significant stenosis
in the subclavian vein. Right ascending venography. Pacemaker
wires are visible. There is a significant stenosis in the subclavian
vein and at the confluence with the internal jugular vein.
A right brachial cephalic autogenous AVA was planned after DUS. In the meantime, the central catheter in the left jugular vein that had been used for dialysis was re-sited in the right jugular vein. The stenoses
in the subclavian and innominate veins underwent intraoperative angioplasty resulting in a satisfactory outcome (Fig. 3).
Patient 2 intraoperative venography and balloon angioplasty.
In the interim between the 2 series, the patient required insertion of a tunneled central venous hemodialysis catheter in the right internal jugular vein. Preliminary intraoperative angiography
demonstrating the stenosis. A 7-mm balloon is passed through the stenosis and inflated. The waist in the balloon is visible at the stenosis (arrow ?central venous catheter; arrowhead ?pacemaker wires). Post angioplasty with a 7-mm balloon. Post angioplasty using an 8-mm balloon showing a better outcome.
Dialysis through the access was begun 6 weeks postoperatively and angiography performed through the indwelling hemodialysis catheter before its removal demonstrated minimal stenosis at the angioplasty site. The fistula is patent at 9 months. Patient 3: This patient had dialysis for 6 years and a kidney transplant after 2 years, that underwent acute rejection. Preoperative venography was performed because of the history of multiple central vein catheter insertions. This showed severe stenosis of the right subclavian vein and complete subclavian vein occlusion on the left. An autogenous AVA was constructed with a transposed basilic vein on the right. Intraoperative angiography was performed through the intermediate basilic vein confirming the preoperative findings and angioplasty was performed with a good outcome. Hemodialysis was initiated through the access 6 weeks postoperatively, but prolonged puncture site bleeding developed. Angiography at 2 months revealed a recurrent subclavian vein stenosis and unsatisfactory angioplasty necessitated the insertion of a wallstent (Boston Scientific, Galway, Ireland) resulting in a good final outcome. The access is patent and functioning well after 14 months.
DISCUSSSION
The ability to create a fistula at a particular site depends on the availability of suitable vessels. Patients on hemodialysis for prolonged periods may have
central vein stenosis or occlusion as a complication of central vein catheterization, posing a major challenge to the creation of any vascular access (8). Central vein stenosis should be ruled out in patients who have had multiple insertions of central lines for prolonged periods of hemodialysis or who have permanent cardiac pacemakers. These stenoses might be discovered during preoperative assessment with DUS, but some stenoses in the proximal subclavian or innominate veins cannot be visualized adequately for precise diagnosis. The gold standard for detection of central vein stenosis
remains ascending venography and should be performed in any patient in whom central vein stenosis is suspected. If this problem is recognized, it is
dealt with some time after the surgery as a separate procedure. The traditional approach to central vein occlusive disease is repeated postoperative angioplasty but it may be necessary to close the AVA in up to 50% of patients (9, 10). Endovascular therapy has been shown to be as efficacious as bypass surgery in dealing with access problems associated with central vein stenosis or occlusion discovered after access construction (11).
If the stenosis is detected preoperatively endovascular intervention could be undertaken at any one of three stages:
Preoperative. In this case there is presumably an excessive risk of immediate occlusion and re-stenosis because of the low velocity flow in veins (12).
Postoperative. This is preferred to preoperative treatment as the established AVA will supposedly provide the necessary high flow to maintain patency in the treated vein, but severe arm edema may develop or the AVA may occlude between the time of the surgery and the endovascular intervention.
Intraoperative. This is now our preferred option because the treated segment is immediately subjected to the new high-flow state in the central veins, and the probability of edema or occlusion may theoretically be the lowest. However treatment of central venous stenosis intraoperatively does not prevent recurrent stenosis and duplex survellance with repeated angioplasty may be needed. In the past we performed endovascular interventions on stenosed central veins a number of weeks after surgery. In our experience with intraoperative angioplasty there were no occurrences of disabling arm edema and no occlusions when managed according to the protocols of our surveillance program. In Patient 1 angioplasty for the recurrent stenosis was not feasible because of chronic kidney rejection and other problems, and arm edema gradually developed. We have decided as a matter of policy to perform endovascular angioplasty in the operating room at the conclusion of fistula construction. Once the access construction has been
completed, endovascular procedures can be carried out via the intermediate cubital or basilic vein branches that are deliberately preserved. The additional
advantage of this sort of timing is that the patient does not need a separate procedure taking up angiography suite time.
This new technique may be applicable to other conditions posing challenges in AVA surgery. In the case of proximal arterial stenosis, intraoperative angioplasty may diminish the risk of severe dialysis access induced steal syndrome. There may also be a place for this technique, less traumatic than metal dilators, in the case of stenoses within veins proposed for AVA construction. This technique may be suitable in construction of prosthetic AVAs as well, with direct puncture of the graft for intraoperative endovascular procecdures at the conclusion of access construction.
We view the introduction of intra-operative endovascular treatment of stenosed central veins during AVA construction as another step forward in
the evolution of techniques required to maximize autogenous AVA construction according to the DOQI (13, 14) recommendations, and for ensuring AVA patency in general.
REFERENCES
1. Shemesh D, Zigelman C, Olsha O, Alberton J, Shapira J, Abramowitz HB. Primary forearm arteriovenous fistula for hemodialysis access - an integrated approach to improve outcomes. Cardiovasc Surg 2003; 11: 35-41.
2. Shemesh D, Olsha O, Berelowitz D, Zaghal I, Zigelman C, Abramowitz HB. An integrated approach to construction and maintenance of prosthetic arteriovenous access for hemodialysis. Vascular 2004; 12: 243-56.
3. Surratt RS, Picus D, Hicks ME, Darcy MD, Kleinhoffer M, Jendrisak M. The importance of preoperative evaluation of the subclavian vein in dialysis access planning. AJR Am J Roentgenol 1991; 156: 623-5.
4. Konner K, Vorwerk D. Permanent pacemaker wires causing subclavian vein stenosis in presence of AV fistula - is it ever wrong to try angioplasty and stenting? Nephrol Dial Transplant 1997; 12: 1735-8.
5. Hernandez D, Diaz F, Rufino M, et al. Subclavian vascular access stenosis in dialysis patients: natural history and risk factors. J Am Soc Nephrol 1998; 9:1507-10.
6. Verstandig AG, Bloom AI, Sasson T, Haviv YS, Rubinger D. Shortening and migration of Wallstents after stenting of central venous stenoses in hemodialysis patients. Cardiovasc Intervent Radiol 2003; 26: 58-64.
7. Shemesh D, Olsha O, Berelowitz D, Zigelman C. An integrated vascular management program. EDTNA ERCA J 2004; 30: 201-7.
8. Lumsden AB, MacDonald MJ, Isiklar H, et al. Central venous stenosis in the hemodialysis patient: incidence and efficacy of endovascular treatment. Cardiovasc Surg 1997; 5: 504-9.
9. Sprouse LR 2nd, Lesar CJ, Meier GH 3rd, et al. Percutaneous treatment of symptomatic central venous stenosis [corrected].J Vasc Surg 2004; 39: 578-82. Erratum in: J Vasc Surg 2004; 39: 867.
10. Surowiec SM, Fegley AJ, Tanski WJ, et al. Endovascular management of central venous stenoses in the hemodialysis patient: results of percutaneous therapy. Vasc Endovascular Surg 2004; 38: 349-54.
11. Bhatia DS, Money SR, Ochsner JL, et al. Comparison of surgical bypass and percutaneous balloon dilatation with primary stent placement in the treatment of central venous obstruction in the dialysis patient: one-year follow-up. Ann Vasc Surg 1996; 10: 452-5.
12. Ward MR, Tsao PS, Agrotis A, Dilley RJ, Jennings GL, Bobik A. Low blood flow after angioplasty augments mechanisms of restenosis: inward vessel remodeling, cell migration, and activity of genes regulating migration. Arterioscler Thromb Vasc Biol 2001; 21: 208-13.
13. The Vascular Access Work Group, NKF-DOQI clinical practice guidelines for vascular access. Am J Kidney Dis 1997; 30 (suppl 3): S150-91.
14. National Kidney Foundation, K/DOQI clinical practice guidelines for vascular access, 2000. Am J Kidney Dis 2001; 37 (suppl 1): S137-81.(D. Shemesh, O. Olsha, D. )
2.Invasive Radiology Unit, Shaare Zedek Medical Center (Affiliated with the Faculty of Health Sciences, Ben-Gurion University of the Negev), Jerusalem - Israel
3.Anesthesiology Department Shaare Zedek Medical Center (Affiliated with the Faculty of Health Sciences, Ben-Gurion University of the Negev), Jerusalem - Israel
ABSTRACT
Central vein stenosis or occlusion due to prior use of central vein hemodialysis catheters may lead to disabling extremity edema or cause early failure after arteriovenous access construction. Our integrated program for arteriovenous access management enables us to identify these stenoses pre-operatively. We carried out
intra-operative angiography and angioplasty during arteriovenous access creation in 3 patients with good immediate and long-term results. Intra-operative endovascular therapy is a new application of peripheral vascular surgery techniques for patients with significant central vein stenosis undergoing access surgery, which exploits the high postoperative flow state to maintain patency after angioplasty. It may also be applicable in situations such as proximal arterial stenosis with anticipated steal syndrome and other conditions that may compromise access patency.
Key Words: Renal dialysis, Surgical arteriovenous shunt, Ultrasonography, Doppler, Duplex, Angioplasty
INTRODUCTION
Many patients with end stage renal disease will require hemodialysis for a prolonged period. Careful preoperative venous and arterial mapping and
planning of the access procedure have minimized failure rates in the setting of a vascular access center (1, 2), utilizing color-coded duplex ultrasonography
(DUS) performed by the surgeon himself. Areas of stenosis and previous inflammation are taken into account in planning the fistula, and the best veins are selected by the surgeon. The arterial tree is also examined carefully in both arms to determine the suitability of the arteries for access creation and the risk of steal syndrome. Patients previously dialyzed via central vein catheters for prolonged periods or those with pacemakers should undergo preoperative venography (3-5). In patients with central vein occlusion or severe stenosis there is a high risk of access failure (6). If the access does not occlude, severe edema may result causing pain and delaying the start of dialysis via the access until postoperative angioplasty is performed. To prevent these potential complications we decided to combine the access surgery with intra-operative endovascular therapy, utilizing the high flow in the access to maintain patency. We describe the technique of central vein transluminal angioplasty carried out intra-operatively during surgery for autogenous arteriovenous access (AVA) construction in 3 patients.
DETAILS OF THE PROCEDURE
Preoperative imaging
All patients were examined preoperatively for planning the AVA according to our protocol (1, 2). DUS was performed by the access surgeon using an Acuson Sequoia 512 (Mountain View, CA, USA) with a 6L3 multifrequency linear array transducer. Preoperative venography was carried out on those patients who required further investigation for central venous stenosis as outlined above. Digital subtraction venography was performed (Siemens Polystar, Siemens, Erlangen, Germany) utilizing concurrent injections from both upper limbs during a single breath hold. Approximately 20 cc. of iopamidol low-osmolar contrast (Iopamiro 370, Bracco s.p.a. Milan, Italy) was injected utilizing veins previously mapped during DUS wherever possible. Normal saline flush and intravenous catheter removal were carried out immediately following the procedure.
Surgical technique
In all cases surgery took place under regional brachial plexus block. Exposure and anastomosis were carried out according to the pre-operative DUS findings. The end to side anastomosis between the cephalic or transposed basilic vein and the brachial artery was completed with preservation of
the intermediate cubital vein and basilic vein branches in all the patients. This enabled insertion of a 7 French introducer sheath through a side
branch after completion of the anastomosis and removal of the clamps, in the setting of a high flow state (Fig. 1).
Intraoperative endovascular procedure
Preliminary digital subtraction angiography was performed (OEC 9800 C-Arm, GE-OEC, Salt Lake City, Utah USA) to locate the previously identified central stenosis. A Berenstein Catheter (Angiodynamics Inc. Queensbury, New York, USA) and Nimble Roadrunner hydrophilic guidewire (Cook Inc. Bloomington, Indiana, USA) were passed through the lesion and angioplasty was performed using a Workhorse II balloon catheter (Angiodynamics Inc. Queensbury, New York, USA). This was followed by completion angiography, removal of the sheath and ligation of the side branch.
Postoperative follow-up
Sutures were removed 10 days postoperatively and patients were examined at 6 weeks by DUS. Hemodialysis was begun using the best available venipuncture sites selected according to the DUS findings and marked for the nephrology team (7). Planned angiography was repeated at 2 months with the aim of examining the treated region of the central vein and carrying out further endovascular treatment if necessary.
CLINICAL EXPERIENCE
Three patients with severe proximal central vein stenosis on pre-operative ascending venography were scheduled for upper arm autogenous AVA construction combined with intra-operative angioplasty (Tab. I).
Patient 1: Preoperative venography showed complete occlusion of the left subclavian and innominate veins precluding the use of that upper extremity
for access. On the right side DUS demonstrated a cephalic vein suitable for autogenous AVA but there was a severe stenosis of the subclavian vein on venography and surgery with operative angioplasty on the right was planned. Before the patient reached surgery a internal jugular catheter was inserted on the right for hemodialysis. A reasonable result was obtained on intraoperative angioplasty with a 40% residual stenosis in the right subclavian vein. The presence of a central venous catheter on the right side, where the new access was constructed, prevented further angioplasty, which was deferred until the access matured. Dialysis through the new access was begun 6 weeks after its
creation and the central venous catheter was removed. The planned post-operative angiography at 2 months showed the subclavian vein to be patent,
and the residual stenosis was angioplastied again. She had a kidney transplant 7 months later and gradually developed significant arm edema over until she died of stroke 6 months after the transplant. Further angioplasty was not carried out because of her precarious medical state. Patient 2: Preoperative ascending venography showed significant stenosis in the left subclavian vein where pacemaker wires entered the vein and significant stenosis at the confluence of the right subclavian and innominate veins (Fig. 2).
Patient 2 preoperative venography. Left ascending venography
with permanent pacemaker. There is a significant stenosis
in the subclavian vein. Right ascending venography. Pacemaker
wires are visible. There is a significant stenosis in the subclavian
vein and at the confluence with the internal jugular vein.
A right brachial cephalic autogenous AVA was planned after DUS. In the meantime, the central catheter in the left jugular vein that had been used for dialysis was re-sited in the right jugular vein. The stenoses
in the subclavian and innominate veins underwent intraoperative angioplasty resulting in a satisfactory outcome (Fig. 3).
Patient 2 intraoperative venography and balloon angioplasty.
In the interim between the 2 series, the patient required insertion of a tunneled central venous hemodialysis catheter in the right internal jugular vein. Preliminary intraoperative angiography
demonstrating the stenosis. A 7-mm balloon is passed through the stenosis and inflated. The waist in the balloon is visible at the stenosis (arrow ?central venous catheter; arrowhead ?pacemaker wires). Post angioplasty with a 7-mm balloon. Post angioplasty using an 8-mm balloon showing a better outcome.
Dialysis through the access was begun 6 weeks postoperatively and angiography performed through the indwelling hemodialysis catheter before its removal demonstrated minimal stenosis at the angioplasty site. The fistula is patent at 9 months. Patient 3: This patient had dialysis for 6 years and a kidney transplant after 2 years, that underwent acute rejection. Preoperative venography was performed because of the history of multiple central vein catheter insertions. This showed severe stenosis of the right subclavian vein and complete subclavian vein occlusion on the left. An autogenous AVA was constructed with a transposed basilic vein on the right. Intraoperative angiography was performed through the intermediate basilic vein confirming the preoperative findings and angioplasty was performed with a good outcome. Hemodialysis was initiated through the access 6 weeks postoperatively, but prolonged puncture site bleeding developed. Angiography at 2 months revealed a recurrent subclavian vein stenosis and unsatisfactory angioplasty necessitated the insertion of a wallstent (Boston Scientific, Galway, Ireland) resulting in a good final outcome. The access is patent and functioning well after 14 months.
DISCUSSSION
The ability to create a fistula at a particular site depends on the availability of suitable vessels. Patients on hemodialysis for prolonged periods may have
central vein stenosis or occlusion as a complication of central vein catheterization, posing a major challenge to the creation of any vascular access (8). Central vein stenosis should be ruled out in patients who have had multiple insertions of central lines for prolonged periods of hemodialysis or who have permanent cardiac pacemakers. These stenoses might be discovered during preoperative assessment with DUS, but some stenoses in the proximal subclavian or innominate veins cannot be visualized adequately for precise diagnosis. The gold standard for detection of central vein stenosis
remains ascending venography and should be performed in any patient in whom central vein stenosis is suspected. If this problem is recognized, it is
dealt with some time after the surgery as a separate procedure. The traditional approach to central vein occlusive disease is repeated postoperative angioplasty but it may be necessary to close the AVA in up to 50% of patients (9, 10). Endovascular therapy has been shown to be as efficacious as bypass surgery in dealing with access problems associated with central vein stenosis or occlusion discovered after access construction (11).
If the stenosis is detected preoperatively endovascular intervention could be undertaken at any one of three stages:
Preoperative. In this case there is presumably an excessive risk of immediate occlusion and re-stenosis because of the low velocity flow in veins (12).
Postoperative. This is preferred to preoperative treatment as the established AVA will supposedly provide the necessary high flow to maintain patency in the treated vein, but severe arm edema may develop or the AVA may occlude between the time of the surgery and the endovascular intervention.
Intraoperative. This is now our preferred option because the treated segment is immediately subjected to the new high-flow state in the central veins, and the probability of edema or occlusion may theoretically be the lowest. However treatment of central venous stenosis intraoperatively does not prevent recurrent stenosis and duplex survellance with repeated angioplasty may be needed. In the past we performed endovascular interventions on stenosed central veins a number of weeks after surgery. In our experience with intraoperative angioplasty there were no occurrences of disabling arm edema and no occlusions when managed according to the protocols of our surveillance program. In Patient 1 angioplasty for the recurrent stenosis was not feasible because of chronic kidney rejection and other problems, and arm edema gradually developed. We have decided as a matter of policy to perform endovascular angioplasty in the operating room at the conclusion of fistula construction. Once the access construction has been
completed, endovascular procedures can be carried out via the intermediate cubital or basilic vein branches that are deliberately preserved. The additional
advantage of this sort of timing is that the patient does not need a separate procedure taking up angiography suite time.
This new technique may be applicable to other conditions posing challenges in AVA surgery. In the case of proximal arterial stenosis, intraoperative angioplasty may diminish the risk of severe dialysis access induced steal syndrome. There may also be a place for this technique, less traumatic than metal dilators, in the case of stenoses within veins proposed for AVA construction. This technique may be suitable in construction of prosthetic AVAs as well, with direct puncture of the graft for intraoperative endovascular procecdures at the conclusion of access construction.
We view the introduction of intra-operative endovascular treatment of stenosed central veins during AVA construction as another step forward in
the evolution of techniques required to maximize autogenous AVA construction according to the DOQI (13, 14) recommendations, and for ensuring AVA patency in general.
REFERENCES
1. Shemesh D, Zigelman C, Olsha O, Alberton J, Shapira J, Abramowitz HB. Primary forearm arteriovenous fistula for hemodialysis access - an integrated approach to improve outcomes. Cardiovasc Surg 2003; 11: 35-41.
2. Shemesh D, Olsha O, Berelowitz D, Zaghal I, Zigelman C, Abramowitz HB. An integrated approach to construction and maintenance of prosthetic arteriovenous access for hemodialysis. Vascular 2004; 12: 243-56.
3. Surratt RS, Picus D, Hicks ME, Darcy MD, Kleinhoffer M, Jendrisak M. The importance of preoperative evaluation of the subclavian vein in dialysis access planning. AJR Am J Roentgenol 1991; 156: 623-5.
4. Konner K, Vorwerk D. Permanent pacemaker wires causing subclavian vein stenosis in presence of AV fistula - is it ever wrong to try angioplasty and stenting? Nephrol Dial Transplant 1997; 12: 1735-8.
5. Hernandez D, Diaz F, Rufino M, et al. Subclavian vascular access stenosis in dialysis patients: natural history and risk factors. J Am Soc Nephrol 1998; 9:1507-10.
6. Verstandig AG, Bloom AI, Sasson T, Haviv YS, Rubinger D. Shortening and migration of Wallstents after stenting of central venous stenoses in hemodialysis patients. Cardiovasc Intervent Radiol 2003; 26: 58-64.
7. Shemesh D, Olsha O, Berelowitz D, Zigelman C. An integrated vascular management program. EDTNA ERCA J 2004; 30: 201-7.
8. Lumsden AB, MacDonald MJ, Isiklar H, et al. Central venous stenosis in the hemodialysis patient: incidence and efficacy of endovascular treatment. Cardiovasc Surg 1997; 5: 504-9.
9. Sprouse LR 2nd, Lesar CJ, Meier GH 3rd, et al. Percutaneous treatment of symptomatic central venous stenosis [corrected].J Vasc Surg 2004; 39: 578-82. Erratum in: J Vasc Surg 2004; 39: 867.
10. Surowiec SM, Fegley AJ, Tanski WJ, et al. Endovascular management of central venous stenoses in the hemodialysis patient: results of percutaneous therapy. Vasc Endovascular Surg 2004; 38: 349-54.
11. Bhatia DS, Money SR, Ochsner JL, et al. Comparison of surgical bypass and percutaneous balloon dilatation with primary stent placement in the treatment of central venous obstruction in the dialysis patient: one-year follow-up. Ann Vasc Surg 1996; 10: 452-5.
12. Ward MR, Tsao PS, Agrotis A, Dilley RJ, Jennings GL, Bobik A. Low blood flow after angioplasty augments mechanisms of restenosis: inward vessel remodeling, cell migration, and activity of genes regulating migration. Arterioscler Thromb Vasc Biol 2001; 21: 208-13.
13. The Vascular Access Work Group, NKF-DOQI clinical practice guidelines for vascular access. Am J Kidney Dis 1997; 30 (suppl 3): S150-91.
14. National Kidney Foundation, K/DOQI clinical practice guidelines for vascular access, 2000. Am J Kidney Dis 2001; 37 (suppl 1): S137-81.(D. Shemesh, O. Olsha, D. )