PERMANENT VASCULAR ACCESS consists

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1 Percutaneous Treatment of Dysfunctional Brescia-Cimino Fistulae Through a Radial Arterial Approach Huang-Joe Wang, MD, and Ya-Fei Yang, MD Background: Dysfunctional Brescia-Cimino fistulae contribute to significant morbidity in hemodialysis patients. These fistulae normally are treated through a retrograde venous approach. There are no data regarding a transradial approach. Furthermore, measurement of pressure reduction in the radial artery appears to be useful. Methods: We retrospectively examined 50 interventions to treat 49 patients (17 men, 32 women; mean age, years) with Brescia-Cimino fistulae. Inclusion criteria were patients with palpable radial arteries and dysfunctional end-to-side Brescia-Cimino fistulae. Patients with infected fistulae, contrast allergy, upper-arm/synthetic graft/central-vein stenosis, and end-to-end Brescia-Cimino fistulae were excluded from the study. Radial arterial pressures before and after angioplasty were compared as a surrogate of stenosis relief. Anatomic and clinical success rates were calculated. Results: Sixty-five stenoses and 4 total occlusions were treated through radial access. All radial punctures were successful, except in 1 patient. Most lesions were located in the cephalic vein (87%). Mean length of treated lesions was cm. Mean pretreatment diameter of lesion stenoses was 76.7% 12.1%. Mean posttreatment diameter stenosis was 22.6% 8.2% (P < 0.001). Systolic, diastolic, and mean blood pressures recorded from the radial artery decreased from , 60 18, and to 88 40, 43 18, and mm Hg (P < 0.001, P < 0.001, and P < 0.001), respectively. The anatomic success rate of the transradial approach was 91.3%. The clinical success rate of the transradial approach was 96%. Conclusion: The transradial approach is a feasible and highly effective approach to treat dysfunctional Brescia-Cimino fistulae. Measuring blood pressure reduction through the radial artery appears promising as a hemodynamic evaluation method. Am J Kidney Dis 48: by the National Kidney Foundation, Inc. INDEX WORDS: Brescia-Cimino fistula; transradial arterial approach; percutaneous transluminal angioplasty. From the Department of Internal Medicine, Division of Cardiology, and Department of Internal Medicine, Division of Nephrology, China Medical University Hospital, Taichung, Taiwan. Received April 17, 2006; accepted in revised form July 17, Originally published online as doi: /j.ajkd on August 28, Support: None. Potential conflicts of interest: None. Address reprint requests to Huang-Joe Wang, MD, Department of Internal Medicine, Cardiology Division, China Medical University Hospital, No. 2, Yuh-Der Rd, Taichung 404, Taiwan. joe5977@ms32.hinet.net 2006 by the National Kidney Foundation, Inc /06/ $32.00/0 doi: /j.ajkd PERMANENT VASCULAR ACCESS consists mainly of primary autogenous arteriovenous fistulae and synthetic polytetrafluoroethylene grafts. 1 Autogenous fistulae usually are created by either a side-to-side or end-to-side vein-to-artery anastomosis of the cephalic vein to radial artery in the wrist (Brescia-Cimino fistula). 2 Despite the superior long-term patency and low infection rate associated with autogenous fistulae compared with synthetic grafts, these autogenous fistulae often become dysfunctional and contribute to significant morbidity in hemodialysis patients. 3 Hyperplastic stenotic lesions frequently are the root cause of dysfunctional fistulae, which are caused by direct venous puncture trauma and differences in compliance of the artery and vein. 4 Such stenotic lesion can lead to thrombosis. Percutaneous transluminal angioplasty (PTA) has gained wide acceptance in the treatment of dysfunctional dialysis access owing to its minimal invasiveness. However, no consensus among professionals was reached regarding the appropriate entry site for treating dysfunctional fistulae. 5-8 Both the retrograde cephalic venous approach and antegrade brachial arterial approach have their supporters. The transradial approach is performed by interventional cardiologists who deal with both coronary and noncoronary procedures because of its low rates of access site related complications, early ambulation with cost reduction, and less invasive characteristics when using coronary devices to treat noncoronary lesions. 9,10 We retrospectively examined our experience using radial access (ie, antegrade approach into the radial artery distal to the radial-cephalic anastomosis) to salvage dysfunctional Brescia-Cimino fistulae. To our knowledge, radial access has never been reported in the literature. Therefore, the purpose of this observational study is to examine 652 American Journal of Kidney Diseases, Vol 48, No 4 (October), 2006: pp

2 RADIAL APPROACH IN BRESCIA-CIMINO FISTULA 653 the feasibility and efficacy of the transradial approach through antegrade radial arterial access to treat dysfunctional Brescia-Cimino fistulae. METHODS Patient Population From February 2004 to November 2005, a total of 49 patients with 50 dysfunctional Brescia-Cimino fistulae were referred by nephrologists to our cardiac catheterization laboratory for PTA. There were 17 men and 32 women with a mean age of years (range, 39 to 80 years). Fistulae were located on the right side in 11 patients and left side in 38 patients. Fistulae were defined as dysfunctional if they met 1 of the following criteria: (1) greater than 50% decrease in normal vessel diameter accompanied by clinical abnormality, such as elevated venous pressure during dialysis, prolonged bleeding after needle withdrawal, decreased blood flow, or increased negative arterial pump pressure that prevented increasing it to an acceptable blood flow; or (2) a fistula could not be successfully punctured to perform dialysis. Inclusion criteria were patients with a palpable radial artery associated with Brescia-Cimino fistulae created by end-to-side anastomosis. Exclusion criteria included patients with: (1) an infected fistula; (2) severe contrast allergy history; (3) a fistula in the upper arm, synthetic graft, or vascular stenoses in the central vein; and (4) an end-to-end Brescia-Cimino fistula. The 50 PTA procedures reported in this study represent a consecutive series of dysfunctional fistulae treated by the authors according to these criteria. All patients gave written informed consent before the PTA procedures took place. Transradial Arterial Puncture Technique Patients were anesthetized locally by using 2% lidocaine at the selected puncture site, usually 1 to 2 cm below the radial artery cephalic venous anastomosis. The radial artery was punctured at a 45 angle with a 30-mm 20-G sheathed needle (BD Angiocath Plus; Becton Dickinson Korea Ltd, Seoul, Korea) and then slowly withdrawn to allow for brisk blood purge from the central hub of the needle. After needle removal, a 45-cm in hydrophilic miniguidewire was inserted through the bleeding hub of the 20-G soft sheath. The 20-G soft sheath was removed and either a 5-Fr (1.67-mm) or 6-Fr (2.00-mm) short sheath (7 cm; Terumo, Leuven, Belgium) was introduced into the radial artery over the miniguidewire near the anastomotic site. The introducer of the sheath was removed, leaving the miniguide wire in place; flushed with normal saline; and connected to the pressure manifold. The downstream fistula stenosis or occlusion was visualized by means of fistulography. This 7-cm short sheath then was fixed in place by using a transparent dressing (Tegaderm; 3M Health Care, St Paul, MN). Typically, no heparin was used if only stenotic lesions were noted. Heparin, 3,000 units, was administered if the lesion was totally occluded or showed an obvious thrombus on the angiogram. If the in miniguidewire was unable to pass through the 20-G soft sheath (eg, weak blood purge), a in coronary wire (Choice PT or PT2; Boston Scientific, Miami, FL) was passed through the central hub of the 20-G soft sheath into either the radial artery or cephalic vein. This in coronary wire has a soft hydrophilic coating on the first 30 cm from the tip, followed by a stiff uncoated part. The stiff portion of the in wire was manipulated to insert the 20-G soft sheath into the radial artery without causing injury. This was followed by removing the in coronary wire, which allowed for brisk blood purge through the hub of the 20-G soft sheath. The in minihydrophilic guidewire then could be inserted into either the cephalic vein or radial artery, followed by insertion of either a 5-Fr or 6-Fr sheath. Hemodynamic Pressure Monitor Blood pressure was measured from the sidearm of a 6-Fr sheath as a surrogate marker of severity of stenosis. In the absence of radial artery stenosis, pressure was recorded from a site upstream from the stenotic downstream venous lesions. Higher pressure recordings denoted more severe downstream lesions, and vice versa. Sheath pressure was measured twice. The first recording was made soon after the sheath was inserted and flushed with saline. The second recording was made after the PTA procedure was completed. The sheath tip was distal to the radial-cephalic anastomosis; its position was verified before and at the end of the PTA procedure. PTA Techniques In patients with stenosis, the lesion was traversed with either a in or in hydrophilic guidewire (Terumo, Tokyo, Japan). A peripheral Wanda balloon (Boston Scientific Ireland, Galway, Ireland) at a 1:1 balloon-vessel ratio was advanced over the guidewire, and the balloon was dilated multiple times up to 6 to 14 atm, usually for 1 minute at a time. The balloon was dilated for up to 3 minutes for cases in which recoil was encountered. If the balloon met with significant resistance, a noncompliant Conquest balloon (Bard, Crawley, UK) at a 1:1 balloon-vessel ratio was used; the balloon then was inflated up to 24 to 28 atm. Occasionally, patients with resistant fistula lesions underwent angioplasty mediated by a cutting balloon. In patients with total occlusion, the lesion was traversed with either a 4-Fr (1.33-mm) JR4 catheter (Cook, Bloomington, IN) coupled with a in hydrophilic guidewire or a 5-Fr FR4 catheter (Boston Scientific, Maple Grove, MN) and a in hydrophilic guidewire. The direction of the guidewire was controlled by the catheter. After the wire was passed through the true lumen, the catheter was advanced to the downstream venous lumen over the hydrophilic guidewire. The guidewire then was removed, leaving the catheter in the true venous lumen. A puff of contrast medium was injected through the catheter to confirm the true lumen of the downstream fistula. The catheter was passed over the hydrophilic guidewire again into the distal fistula to aid in removal of the catheter. The balloon inflation procedure that followed was identical to that performed for stenotic lesions. At the end of the intervention, the short sheath was removed immediately and the puncture site was manually compressed for 5 to 15 minutes until hemostasis was obtained. Great care was given to avoid compression of the anastomotic site. After hemosta-

3 654 sis was achieved, pulsation of the intact radial artery was confirmed. A small compressive bandage was placed over the radial puncture site for 4 hours to ensure adequate hemostasis. Patients were able to undergo hemodialysis soon after hemostasis was achieved. Angiographic Analysis Digital angiograms were reviewed by the operator retrospectively. The method for calculating percentage of stenosis was modified from the quantitative coronary angiogram: Diameter stenosis ([reference vessel diameter target lesion diameter] Reference vessel diameter) 100% The reference vessel chosen generally was the vein upstream from the lesion. 11 Diameter stenosis was calculated automatically by using commercial software (Centricity Cardiology CA 1000, V1.0; GE Medical Systems, Waukesha, WI). Study Outcomes and Definitions Total procedure time was measured from the start of percutaneous transradial puncture to completion of the PTA procedure; it did not include time to achieve hemostasis. Total fluoroscopy time is a measure of the low-dose radiation that was adequate to create a television image; this real-time motion image was used to perform the wiring, balloon/catheter positioning, and test contrast injection. This measure was calculated automatically by the cardiac catheterization machine. Total contrast volume is total amount of contrast medium actually injected into the patient. Procedure outcomes are defined according to the definition proposed by the Society of Interventional Radiology; slight modification was made to include the transradial approach. 12 Anatomic success for the treated lesions is defined as achievement of stenosis less than 30% of the residual diameter after successful transradial approach. Clinical success is defined as at least 1 successful hemodialysis session after successful transradial approach. Statistical Analysis Statistical analyses were performed using SPSS 10.0 statistical software for Windows (SPSS Inc, Chicago, IL). Discrete variables are presented as percentages, and continuous variables, as mean SD. Paired t-test was used to determine the significance of the difference between continuous variables. P less than 0.05 is considered statistically significant. RESULTS Procedural Characteristics Forty-nine patients with 50 dysfunctional Brescia-Cimino fistulae were enrolled in this study. Sixty-nine lesions were treated by means of PTA. The transradial approach was performed with a 6-Fr sheath in 46 interventions and a 5-Fr sheath in 4 interventions. All transradial punctures were successful, except in 1 patient for WANG AND YANG Table 1. Number and Size of Angioplasty Balloons Used in 50 Interventions No. of balloons 1 9 (18) 2 20 (40) 3 15 (30) 4 4 (8) 5 2 (4) Maximal balloon diameter (mm) 3 1 (2) 4 4 (8) 5 18 (36) 6 19 (38) 7 7 (14) 8 1 (2) NOTE. Values expressed as number of interventions (percent). whom the transradial approach failed because of intense spasm after the initial puncture failure. Retrograde cephalic venous puncture was necessary to complete the PTA procedure. Numbers and sizes of angioplasty balloons are listed in Table 1. Mean number of balloons used per intervention was (median, 2 balloons; range, 1 to 5 balloons). Mean maximal balloon diameter was mm (median, 6 mm; range, 3 to 8 mm). Total procedure time was minutes (range, 15 to 75 minutes), and total fluoroscopy time, minutes (range, 2.8 to 23.3 minutes). Mean total contrast volume was ml (range, 40 to 200 ml). Angiographic Measurements and Procedure Outcomes Preinterventional angiographic findings of the 69 lesions in 50 Brescia-Cimino fistulae are listed in Table 2. Mean length of treated lesions was cm (range, 0.4 to 15 cm). Pretreatment diameter stenosis of lesions was 76.7% 12.1% (range, 54.3% to 100%). Posttreatment diameter stenosis was 22.6% 8.2% (range, 5.0% to 50.0%; P 0.001). The anatomic success rate of the transradial approach for treating lesions was 91.3% (63 of 69 lesions). Anatomic failure caused by residual stenosis greater than 30% was seen in 5 lesions treated by using the transradial approach. The radial approach failed in 1 lesion. All procedures were uncomplicated. All patients were able to undergo hemodialysis after the PTA procedures except for 1 patient, for

4 RADIAL APPROACH IN BRESCIA-CIMINO FISTULA 655 Table 2. Preinterventional Angiographic Characteristics of the 69 Treated Lesions Lesion Characteristic No. of Lesions (n 69) Type Stenosis 65 (94.2) Total occlusion 4 (5.8) Location Cephalic vein within 5 cm of RC anastomosis 42 (60.9) Cephalic vein beyond 5 cm of RC anastomosis 18 (26.1) Median cubital vein 5 (7.2) Radial artery anastomosis site 2 (2.9) Basilic vein 2 (2.9) Lesion length (cm) NOTE. Values expressed as number of lesions (percent) or mean SD. Abbreviation: RC anastomosis, radial artery to cephalic vein anastomosis. whom total occlusion was noted 1 day later. A repeated transradial approach procedure was successful. The cause of occlusion was inadvertent manual compression of the anastomotic site during the hemostasis process. The clinical success rate of the transradial approach therefore was 96% (48 of 50 lesions), with 1 failure in radial artery puncture and another failure in fistula occlusion before undergoing successful hemodialysis. Hemodynamic Measurement Radial artery pressure (antegrade to the stenotic lesion) measured from the sheath sidearm showed a significant decrease after PTA procedures in our patients. Systolic blood pressure decreased from mm Hg pretreatment to mm Hg posttreatment (P 0.001). Diastolic blood pressure decreased from mm Hg pretreatment to mm Hg posttreatment (P 0.001). Mean blood pressure decreased from mm Hg pretreatment to final mm Hg posttreatment (P 0.001). DISCUSSION The transradial approach for coronary procedures has gained widespread acceptance since it was introduced first by Campeau 13 in As noted in a recent meta-analysis of randomized trials, the radial approach can virtually eliminate local vascular complications. 14 Noncoronary transradial approaches, including transmyocardial revascularization, renal artery stenting, vertebral artery stenting, and mesenteric artery stenting, also were reported In this study, we managed dysfunctional Brescia-Cimino fistulae through the transradial approach. The excellent anatomic and clinical success rates found in our study support this approach for its general use in treating dysfunctional fistulae. Hemodialysis fistula lesions frequently are located in downstream veins near the arteriovenous anastomotic site. 19 Most investigators treated dysfunctional fistulae by means of venous puncture downstream from the lesion for their PTA technique. 4,5,20,21 A retrograde venous approach is considered the standard approach for managing Brescia-Cimino fistulae 5 ; however, this approach poses several inherent limitations. First, the lesion can be more difficult to evaluate because of contrast medium dilution by upstream arterial blood. This problem can be obviated in part by using a blood pressure cuff above the elbow; however, when side branches exist between the arteriovenous anastomosis and retrograde puncture site, the afferent radial artery sometimes is poorly depicted after injection of the venous contrast medium. 22 Second, lesions downstream from the puncture site cannot be treated by using a retrograde sheath and therefore require an additional sheath. Third, occlusion in the peripheral lesion of Brescia-Cimino fistulae is more difficult to treat through the retrograde approach; the reported success rate is only 65%. 23 Brachial arterial puncture and multiple venous sheaths are necessary to increase the success rate of treating occluded fistulae. 7,21,24 Fourth, hemostasis applied directly to outflow fistulae increases the risk for shunt thrombosis in patients with suboptimal PTA results. These drawbacks can be avoided by using the transradial approach. First, the antegrade location of the radial artery will make the downstream vascular anatomy from the radial artery to the central veins clearly visualized by using contrast medium injection. Second, 1 sheath is sufficient to treat all downstream lesions from the radial arterial anastomotic site to the central vein. Third, total occlusion also can be treated successfully with 1 sheath. Fourth, hemostasis is applied directly to the radial artery without interfering with the entire treated fistula, lessening the

5 656 risk for occlusion after the PTA procedure. We noted only 1 subacute occlusion in our series; the problem was caused by inadvertently applying hemostasis to the anastomotic site. In addition to the transradial approach, brachial artery access also can overcome the inherent drawbacks of venous puncture. Haage et al 6 recommended routine puncture of the brachial artery with a 22-G sheath needle as a diagnostic method before performing PTA. Furthermore, Manninen et al 7 adopted a direct interventional approach through the brachial artery by using either a 5-Fr or 6-Fr sheath after pretreatment with 5,000 units of heparin. Despite resolving the visualization problem by using the brachial artery, the diagnostic brachial approach still uses the retrograde vein to perform the intervention. Furthermore, it does not solve the occlusion problem and requires multiple sheaths. Although the interventional brachial approach can be used to treat total occlusion in 1 sheath, it has a reported complication rate of 12% after removal of the sheath. 7 Furthermore, treatment of upperarm fistulae and central veins through the brachial approach is problematic because of the balloon length and U-turn curvature in the arteriovenous anastomosis, resulting in difficulty advancing the PTA balloon. An additional sheath inserted antegrade into the downstream vein is necessary to overcome the problem. Conversely, the radial artery approach is appealing to interventionists who deal with hemodialysis fistulae because it does not pose complications and can be used to treat all downstream lesions with 1 sheath in an antegrade fashion. Most Brescia-Cimino fistulae have straight lesions downstream from the radial artery puncture site; only rarely does the radial artery approach encounter a difficult U-turn. We do not use heparin in patients with stenotic lesions because neither inflow nor outflow blood is impeded by the sheath. This can partially explain the lack of complications after removal of the radial sheath. Another reason for lack of local hemostasis complications is the great decrease in radial pressure caused by relief of the stenosis or occlusion after the PTA procedure, making hemostasis easier. Sullivan et al 25 recommended that an intragraft venous limb static systolic/cuffed brachial systolic pressure less than 0.33 or an intragraft arterial limb systolic pressure/cuffed pressure WANG AND YANG less than 0.5 be used to define hemodynamic success. We did not use their criteria because the brachial artery, polytetrafluoroethylene graft, and downstream venous system are larger compared with radial-cephalic fistulae. In addition, graft lesions in the report by Sullivan et al 25 were closer to central venous systems than in our study. Direct comparison with such criteria therefore was not suitable. We adopted hemodynamic measurement from the sidearm of the sheath to assist in evaluation of stenosis reduction. Generally, we observed a decrease of about one third in systolic, diastolic, and mean blood pressures after the PTA procedure in our patients. Only PTA at the radial artery anastomotic site can invalidate such sheath pressure measurements through the radial artery. This significant decrease in pressure is compatible with our high anatomic success rate in this study. Radial sheath pressure measurement accompanied by the transradial approach appears promising as hemodynamic evaluation of stenosis reduction; however, the definite criterion for hemodynamic success through the transradial approach is unknown in native fistulae at the present time and needs further study. Treatment of thrombotic Brescia-Cimino fistulae without prior use of mechanical thromboaspiration has incurred intense debate. 26 The most dreadful complication is pulmonary embolism caused by maceration of a large thrombus by the balloon. Fortunately, our 4 patients with occlusion showed a relatively low thrombus burden; all were treated by using balloon angioplasty without prior thrombolytics or thromboaspiration. No respiratory distress was noted during or immediately after the PTA procedure in these 4 patients. We agree with Liang et al 24 that thromboaspiration before PTA may not be necessary in patients for whom the burden of thrombus is not large. However, large thrombotic aneurysms still may require pharmacomechanical thrombolysis, possibly combined with distal protection devices, if a patient refuses to undergo surgery. The major limitation of the transradial approach is possible access failure because of the smaller radial artery size and end-to-side cephalic vein-to-radial anastomosis. True puncture failure through the transradial approach was reported to be as low as 0.25%. 27 However, the normal radial artery encountered in routine coronary

6 RADIAL APPROACH IN BRESCIA-CIMINO FISTULA 657 procedures by cardiologists is not anastomosed to a vein and has no problems of arterial-venous anastomotic stenosis or downstream venous stenosis. Both conditions will impede the smooth passage of a in short hydrophilic guidewire and make insertion of a sheath impossible. We adopted a in hydrophilic coronary wire to assist in our puncture success. Only 1 puncture failure during the transradial approach was noted in the present study. Dysfunctional Brescia-Cimino fistulae can be treated safely and efficaciously through the transradial arterial approach. This technique virtually eliminates the drawbacks associated with the retrograde venous and brachial approaches. Furthermore, the decrease in radial artery pressure appears to be a promising hemodynamic evaluation of stenosis reduction. For interventionalists dealing with dysfunctional Brescia-Cimino fistulae, the transradial approach is a simple and highly effective method with excellent anatomic and clinical outcomes. REFERENCES 1. Berkoben MJ, Schwab SJ: Hemodialysis vascular access, in Henrich WL (ed): Principles and Practice of Dialysis (ed 3). Philadelphia, PA, Lippincott, Williams & Wilkins, 2004, pp Brescia M, Cimino J, Appel K, Hurwich B: Chronic hemodialysis using venipuncture and a surgically created arteriovenous fistula. N Engl J Med 275: , Ackad A, Simonian GT, Steel K, et al: A journey in reversing practice patterns: A multidisciplinary experience in implementing DOQI guidelines for vascular access. Nephrol Dial Transplant 20: , Turmel-Rodrigues L, Raynaud A, Shapoval M, Beyssen B: Interventions in dialysis fistulas, in Dyet JF, Ettles DF, Nicholson AA, Wilson SE (eds): Textbook of Endovascular Procedures. 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7 Liang HL, Pan HB, Chung HM, et al: Restoration of thrombosed Brescia-Cimino dialysis fistulas by using percutaneous transluminal angioplasty. Radiology 223: , Sullivan KL, Besarab A, Bonn J, Shapiro MJ, Gardiner GA Jr, Moritz MJ: Hemodynamics of failing dialysis grafts. Radiology 186: , 1993 WANG AND YANG 26. Turmel-Rodrigues L: Underestimated drawbacks of combined simple dilation and thrombolytics for restoration of thrombosed Brescia-Cimino dialysis fistula. Radiology 226: , 2002 (letter) 27. Louvard Y, Lefèvre T: Loops and transradial approach in coronary diagnosis and intervention. Catheter Cardiovasc Interv 51: , 2000