Surgical Treatment of Cephalic Arch Problems in Arteriovenous Fistulas: A Center Experience

Accepted Manuscript Surgical treatment of cephalic arch problems in arteriovenous fistulas: a center experience Mónica Fructuoso, Joana Ferreira, Pedro Sousa PII:

S0890-5096(18)30076-1

DOI:

10.1016/j.avsg.2017.11.034

Reference:

AVSG 3656

To appear in:

Annals of Vascular Surgery

Received Date: 9 May 2017 Revised Date:

3 October 2017

Accepted Date: 2 November 2017

Please cite this article as: Fructuoso M, Ferreira J, Sousa P, Surgical treatment of cephalic arch problems in arteriovenous fistulas: a center experience, Annals of Vascular Surgery (2018), doi: 10.1016/j.avsg.2017.11.034. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT CASE REPORT

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TITLE:

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Surgical treatment of cephalic arch problems in arteriovenous fistulas: a center

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experience.

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Mónica Fructuosoa, Joana Ferreirab, Pedro Sousac

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Faculdade de Ciências da Saúde da Universidade da Beira Interior, Covilhã, Portugal

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Nephrology Department, Centro Hospitalar de Trás os Montes e Alto Douro EPE, Vila Real, Portugal;

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Vascular Surgery Department, Centro Hospitalar de Trás os Montes e Alto Douro EPE, Vila Real,

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Portugal

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Real, Portugal

Interventional Radiology Department, Centro Hospitalar de Trás os Montes e Alto Douro EPE, Vila

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Corresponding author: Mónica Fructuoso

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Adress:

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Serviço de Nefrologia, Centro Hospitalar de Trás os Montes e Alto Douro EPE

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Avenida da Noruega

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5000-508 Vila Real, Portugal

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E-mail: [email protected]

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This research did not receive any specific grant from funding agencies in the

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public, commercial, or not-for-profit sectors.

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ACCEPTED MANUSCRIPT ABSTRACT

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Introduction:

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Cephalic arch problems, mainly stenosis (CAS), are a common cause of arteriovenous

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fistulas (AVFs) failure and the most effective treatment is yet to be clearly defined.

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Restenosis usually occurs soon and multiple interventions become necessary to

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maintain patency and functionality.

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The authors present the experience of their center with cephalic vein transposition in a

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group of patients with different problems involving the cephalic arch.

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Material and Methods:

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After consultation of the medical records, an observational retrospective analysis was

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performed to evaluate the outcomes of surgical treatment in cephalic arch problems of

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AVFs treated at the author’s center between January of 2013 and December of 2015.

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The considered outcomes were endovascular intervention rate, thrombosis rate, primary

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and secondary patencies.

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Results:

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Seven patients were treated by venovenostomy with transposition of the cephalic arch

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and anastomosis to the axillary vein. The average age was 72 years (59-81), most were

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female (71%) and diabetic (71%). All accesses were brachiocephalic AVFs with a mean

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duration of 4 years (1-7). The underlying problems were intrinsic CAS (n=5),

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entrapment of the cephalic vein (n=1) and clinically significant vein tortuosity at the

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cephalic arch (n=1). These last 2 problems conducted to a surgical approach as first-line

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ACCEPTED MANUSCRIPT therapy instead of endovascular intervention, the initial treatment in the other 5 cases

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(all with high pressure balloons, with cutting-balloon in one case). Previous thrombotic

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episodes were reported in 57% of the patients. The mean access flow before surgical

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intervention was 425 ml/min (350-1500).

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No complications related with the surgical procedure were reported. One patient

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underwent surgical thrombectomy after AVF thrombosis, followed by transposition of

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the vein. In another case, a simultaneously flow reduction was performed. Most of the

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patients on dialysis (5/6) used the AVF after surgery.

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After a mean follow-up period of 9 months (1-22), surgical treatment was associated

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with a reduction in endovascular intervention rate (1.9 interventions per patient-year

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pre-surgery vs 0.4 post-surgery ; p<0.05) and thrombosis rate (0.93 thrombotic episodes

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per patient-year pre-surgery vs 0.17 post-surgery; p<0.05). The problems leading to

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endovascular reintervention were: new venous anastomosis stenosis (57%), axillary

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vein stenosis (29%) and swing-point stenosis (14%). Primary and secondary patency at

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6 months were 57% and 71%, respectively.

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Conclusions:

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In this group of patients with cephalic arch problems and multiple previous procedures,

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surgical treatment was associated with a reduction in endovascular intervention and

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thrombosis rate, but didn’t avoid reintervention. Facing the complexity and multiplicity

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of the cephalic arch complications, treatment should be individually decided.

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1- INTRODUCTION The failure of a functioning autologous access in dialysis results in significant morbidity

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and mortality in patients with end-stage renal disease. It is well known nowadays, based

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on relatively large series [1], that most upper arm fistula failure are due to outflow

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disease, with a significant number of problems located in the cephalic arch. This portion

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of the cephalic vein has a unique morphology, with a variable curvature and an

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involvement in an aponeurotical conduit that crosses the deltopectoral and

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claviculopectoral fascias [2]. The pressure increase and the shear forces caused by the

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higher flow of brachiocephalic fistulas (BCFs), with exclusive drainage via the cephalic

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vein, combined with the flow direction change in the curvature predispose to intimal

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hyperplasia and subsequent stenosis. The larger number of valves in the cephalic

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outflow and the higher predisposition to wall thickening and intimal hyperplasia in

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patients with renal failure are other potentially involved factors in the development of

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venous stenosis [3]. Entrapment of the vein due to extrinsic compression is also

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possibly troublesome.

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Cephalic arch stenosis (CAS) has been reported in 39% to 77% of dysfunctional BCFs,

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with only 2% to 20% in lower arm fistulas [4, 5]. The lower flow and multiple venous

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drainage of radio-cephalic fistulas justifies the smaller incidence of CAS in this type of

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access. CAS can lead to access flow reduction and thrombosis, sometimes combined

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with aneurysmatic degeneration of the cephalic vein.

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Multiple management strategies have been described in literature for CAS, from

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percutaneous intervention to surgical treatment, however, the most effective treatment

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for cephalic arch problems is yet to be clearly defined [3,6]. Restenosis usually occurs

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soon and multiple interventions become necessary to maintain patency and

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ACCEPTED MANUSCRIPT functionality. Additionally, cephalic arch problems complexity can be potentiated by

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the coexistence of high-flow, that correlates directly with intimal hyperplasia [7,8] and

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entrapment.

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Surgical options like vein transposition, venoplasty and bypass have been described

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mostly in small patient groups with varying results [9-12]. The authors present the

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experience of their center with cephalic vein transposition in a group of patients with

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different problems involving the cephalic arch.

2- MATERIAL AND METHODS:

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Patients and study design

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An observational retrospective study was conducted. Clinical data regarding all patients

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with an arteriovenous fistula (AVF) and cephalic arch problems surgically treated in the

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author’s center between January of 2013 and December of 2015 was collected. Patient’s

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medical records were assessed for demographic information (age, gender), presence of

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diabetes, type and duration of the AVF, underlying problems (stenosis, high-flow, steal-

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syndrome), type and number of previous percutaneous or surgical interventions and

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related complications.

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The vascular access (VA) problem was usually initially detected in our dialysis units

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where a surveillance program is implemented. This program includes periodic clinical

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evaluation of the VA by an experient nephrologist complemented by flow evaluation on

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BTM® (blood temperature monitor). All patients are subsequently directed to our

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Vascular Access Clinic for a duplex scan and treatment decision. If a cephalic arch

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ACCEPTED MANUSCRIPT problem is diagnosed, intervention is recommended in all patients with significant

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stenosis (≥50%) and clinical repercussion (hyperpulsatility, bleeding, aneurysmal

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growth…) or decreasing flow (≥25%). A flow reduction procedure is advised when VA

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flow is above 1500 ml/min.

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Only the patients with cephalic arch problems treated surgically were selected for the

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study. A before and after-surgery analysis was performed. Patients were evaluated for

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endovascular cephalic arch interventions per access-year, thrombotic episodes per

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access-year and patency after surgical intervention. Primary patency interval was

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defined until the first endovascular intervention after surgery to maintain AVF patency

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and secondary patency until the access loss.

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Surgical procedure

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Surgical technique consisted of venovenostomy with transposition of the cephalic arch

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and anastomosis to the axillary vein (Figures 1-4), performed in all cases by the same

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surgeon. Before surgery, all patients had an ultrasound scan for flow evaluation, correct

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identification of the axillary vein, marking of the new path to avoid excessive

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angulation and the preferable location of the new venous anastomosis. All procedures

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were performed under regional anesthesia and antibiotic prophylaxis with cefazolin.

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After approach and isolation of the cephalic and axillary veins (Figure 1), cephalic vein

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was marked to avoid rotation (Figure 2) and tunneled to the axillary vein (Figure 3)

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using 3 to 4 incisions (Figure 4). Regarding the different biotypes and variable anatomy

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in the axilla, vein angulation is also variable between patients, but performed with the

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widest possible angle. The new venous anastomosis was performed with 6/0 prolene.

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ACCEPTED MANUSCRIPT 158

If flow reduction is necessary, the surgical techniques used in our center are cephalic

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vein plication after the arterio-venous anastomosis or modified Miller banding

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procedure.

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Data analysis:

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Before and after-surgery endovascular intervention and thrombosis rates were compared

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using a paired t-test. Kaplan-Meier analysis was performed to estimate patencies.

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3- RESULTS:

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During the study period, seven patients were treated by venovenostomy with

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transposition of the cephalic arch and anastomosis to the axillary vein. The average

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patient age was 72 years (range 59-81), 71% were female and 71% had diabetes.

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Demographic and clinical variables of all patients are described in detail in Table I.

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All accesses were brachiocephalic AVFs, with a mean duration of 4 years (range, 1-7).

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The diagnosed problems were intrinsic cephalic arch stenosis (n=5), entrapment of the

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cephalic vein (n=1) and clinically significant vein tortuosity (n=1). The 5 cases of CAS

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were previously submitted to percutaneous angioplasty, all with high pressure balloons

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and a cutting-balloon in one patient. In this case, the use of cutting-balloon improved

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the immediate result, but had no additional benefit in the restenosis rate comparing to

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simple balloons. Entrapment of the cephalic vein (n=1) and clinically significant vein

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tortuosity (n=1) conducted to a surgical approach as first-line treatment. None of these

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two patients presented high-flow fistulas.

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ACCEPTED MANUSCRIPT Four patients (57%) had previous thrombotic episodes. One patient underwent surgical

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thrombectomy followed by transposition of the vein.

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The mean access flow before surgical intervention was 425 ml/min (range, 350-1500).

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In one patient with CAS and high flow (1500 ml/min), submitted to multiple

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endovascular interventions (4) with high-pressure balloons, simultaneously flow

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reduction was performed through vein plication.

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No complications related to the surgical procedure were reported. Most of the patients

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on dialysis (5/6) used AVF after surgery, without the need for central venous catheter.

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One patient developed post-surgical arm oedema that prevented the immediate use of

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the AVF.

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After a mean follow-up period of 9 months (range, 1-22), surgical treatment was

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associated with a reduction in endovascular intervention rate (1.9/patient/year before

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surgery

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(0.93/patient/year before surgery and 0.17/patient/year after surgery, p<0.05)- Table II.

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All patients needed endovascular reintervention after surgery with standard angioplasty,

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mainly because of new venous anastomosis stenosis (57%)- Table III.

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Primary and secondary patencies at 6 months were 57% and 71%, respectively.

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p<0.05)

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4- DISCUSSION:

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No definitive management strategy exists for CAS. Systematic reviews conclude that

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studies are limited by being primarily single-center retrospective trials featuring

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heterogenous patient populations, interventions, and endpoints [13]. 9

ACCEPTED MANUSCRIPT We were able to find different etiologies for the cephalic arch problems, that conducted

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to distinct treatment approaches. In some specific problems like entrapment and vein

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tortuosity, surgical treatment was considered the preferred approach. In patients with

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intrinsic CAS, surgical treatment was reserved for recurrent stenosis after multiple

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percutaneous angioplasties. In the presence of a high flow AVF, flow reduction was

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simultaneously performed. Surgical treatment was associated with a reduction in

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endovascular intervention and thrombosis rate, but didn’t avoid reintervention.

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The effectiveness of percutaneous interventions like transluminal angioplasty (PTA)

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with low or high-pressure balloons, cutting-balloons, bare metal stents and stent grafts

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has been studied in CAS, but with limited efficacy. Hammes et al. demonstrated higher

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thrombosis rate in patients with CAS and higher angioplasty resistance with 2.1% of

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patients requiring stents [5]. These stenosis frequently require high-pressure balloons

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and restenosis after angioplasty is common, with 6 month primary patency rates lesser

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than 50% [1, 14]. Stent grafts have proved better results when compared with bare metal

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stents or balloon angioplasty [15,16]. Cutting-balloons had similar results in other

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studies [17].

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Surgical treatment includes in the majority of cases venovenostomy with transposition

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of the cephalic arch to the basilic or axillary veins and flow reduction. All published

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data regarding surgical options consist mainly in rectrospective studies and a small

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number of patients. Kian et al demonstrated post-surgery patencies at 6 and 12 months

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of 69% and 39%, respectively, in 13 patients with angioplasty [10]. Prospective studies

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comparing endovascular intervention to surgery are missing.

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In our center, the initial treatment decision depends on the type of problem at the

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cephalic arch. The mainstay of treatment for CAS is PTA with a simple balloon.

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ACCEPTED MANUSCRIPT Cutting-balloons may be used in the absence of response to high-pressure balloons and

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indications for stent graft include significant residual stenosis after the previous

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endovascular procedures and uncontrolled rupture. Our limited use of stent grafts in

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CAS relates with the difficulties caused by the vein curvature in the cephalic arch and

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the angle of the cephalic-axillary confluence, possible migration and intra-stent stenosis.

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Verstanding et al. overstepped the confluence problem passing a stiff Amplatz

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guidewire retrograde into the axillary vein from the confluence, increasing its

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perpendicularity [6]. We also believe that the use of stent grafts may also jeopardize a

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surgical option in the future of the vascular access. In recurrent clinically relevant

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stenosis (more than 3 PTA procedures in the last year), with less than 3 months after the

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last successful angioplasty, we perform surgical treatment.

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Transposition of the cephalic vein to the axillary vein provides good initial results but

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stenosis of the new venous anastomosis is a latter problem, as it has been referred in

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previous papers [11] and confirmed in our group of patients. However, these stenosis

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responded to PTA in our study and the surgical procedure was associated with a

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significant reduction in endovascular intervention and thrombosis rates. Our primary

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patency at 6 months was inferior to other studies [11, 12] but comparable to series of

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surgical treatment where patients had been previously submitted to endovascular

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procedures. Kian et al. [10] evaluated 13 patients with CAS recurring after PTA, with

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12 months primary patency of only 39%. Wang et al. [18] found a 12 months primary

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patency of only 12% in patients treated with cephalic vein transposition with preceding

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PTA compared to 58% in previously untreated patients. These data suggest a negative

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impact of percutaneous interventions in the surgery outcome. The authors believe that if

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total exclusion of the damaged and fibrous segment of vein during surgery is possible,

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ACCEPTED MANUSCRIPT this may contribute to a better response of the new anastomosis stenosis to angioplasty,

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has occurred in our patients.

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High flow is a significant trigger for intimal hyperplasia [19] and flow reduction has

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proved efficacy in reducing the recurrence of CAS. Miller et al. demonstrated that flow

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reduction in patients with CAS was associated with an intervention rate reduction from

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3.34 prebanding to 0.9 postbanding [20]. One patient in our series was submitted to

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transposition of the vein and simultaneous flow reduction. This was a case of recurrent

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CAS and previous PTA, with rapid restenosis after the last endovascular procedure.

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Limitations in our study include the small number of patients and its retrospective

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nature.

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5- CONCLUSIONS:

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In this group of patients with cephalic arch problems and multiple previous procedures,

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surgical treatment was associated with a reduction in endovascular intervention and

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thrombosis rate, but didn’t avoid reintervention. Facing the complexity and multiplicity

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of the cephalic arch complications and in the absence of randomized controlled trials

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comparing percutaneous and surgical approaches, treatment should be individually

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decided.

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Acknowledgements:

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To Dr. Norton de Matos, Vascular Surgeon.

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6- REFERENCES [1] Turmel-Rodrigues L, Pengloan J, Baudin S, et al. Treatment of stenosis and

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thrombosis in haemodialysis fistulas and grafts by interventional radiologi. Nephrol

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Dial Transplant. 2000; 15 (12): 2029-2036.

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[2] Yeri LA, Houghton EJ, Palmieri B, Flores M, Gergely M, Gomez JE. Cephalic vein.

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Detail of its anatomy in the deltopectoral triangle. International Journal of Morphology.

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2009. 27 (4): 1037-1042.

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[3] Gajan S, Leo M, Neil JH. Cephalic arch stenosis in dialysis patients: review of

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clinical relevance, anatomy, current theories on etiology and management. J Vasc

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Access. 2014. 15(3): 157-162.

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[4] Rajan DK, Clark TW, Patel NK, Stavropoulos SW, Simons ME. Prevalence and

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treatment of cephalic arch stenosis in dysfunctional autogenous hemodialysis fistulas. J

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Vasc Interv Radiol. 2003. 14(5): 567-573.

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[5] Hammes MS, Boghosian ME, Cassel KW, Funaki B, Coe FL. Characteristic

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differences in cephalic arch geometry for diabetic and non-diabetic ESRD patients.

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Nephrol Dial Transpl. 2009; 24(7): 2190-2194.

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[6] Verstandig AG, Shemesh D. Managing cephalic arch stenosis. Endovascular Today.

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2012; 63-65.

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[7] Heise M, Schmidt S, Kruger U, et al. Local haemodynamics and shear stress in

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cuffed and straight PTFE-venous anastomosis: an in-vitro comparison using particle

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image velocimetry. Eur J Vasc Endovasc Surg. 2003; 26: 367-73.

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[8] Jaberi A, Schwartz D, Marticorena R, et al. Risk factors for the development of

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cephalic arch stenosis. J Vasc Access. 2007; 8: 287-95.

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ACCEPTED MANUSCRIPT [9] Shenoy S. Cephalic arch stenosis: surgery as first line therapy. J Vasc Access. 2007;

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8:149-151.

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[10] Kian K, Unger SW, Mishler R, Schon D, Lenz O, Asif A. Role of surgical

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intervention for cephalic arch stenosis in the “fistula first” era. Semin Dial. 2008; 21

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(1): 93-96.

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[11] Chen JC, Kamal DM, Jastrzebski J, Taylor DC. Venovenostomy for outflow

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venous obstruction in patients with upper extremity autogenous hemodialysis

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arteriovenous access. Ann Vasc Surg. 2005 Sep;19 (5):629-35.

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[12] Sigala F, Saßen R, Kontis E, et al. Surgical treatment of cephalic arch stenosis by

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central transposition of the cephalic vein. J Vasc Access 2014; 15 (4): 272-277.

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[13] Vasanthamohan L, Gopee-Ramanan P, Athreya S. The Management of Cephalic

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Arch Stenosis in Arteriovenous Fistulas for Hemodialysis: A Systematic Review.

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Cardiovasc Intervent Radiol. 2015 Oct; 38(5):1179-85.

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[14] Hammes M, Funaki B, Coe FL. Cephalic arch stenosis in patients with fistula

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access for hemodialysis: relationship to diabetes and thrombosis. Hemodial Int. 2008;

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12: 85-89.

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[15] Shemesh D, Goldin I, Zaghal I, Berlowitz D, Raveh D, Olsha O. Angioplasty with

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stent graft versus bare stent for recurrent cephalic arch stenosis in autogenous

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arteriovenous access for hemodialysis: a prospective randomized clinical trial. J Vasc

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Surg. 2008; 48(6): 1524-1531.

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[16] Rajan DK, Falk A. A Randomized Prospective Study Comparing Outcomes of

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Angioplasty versus VIABAHN Stent-Graft Placement for Cephalic Arch Stenosis in

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Dysfunctional Hemodialysis Accesses. J Vasc Interv Radiol. 2015 Sep; 26(9):1355-61.

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ACCEPTED MANUSCRIPT [17] Heerwagen ST, Lonn L, Schroeder TV, Hansen MA. Cephalic arch stenosis in

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autogenous brachiocephalic hemodialysis fistulas: results of cutting balloon angioplasty.

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J Vasc Access. 2010; 11 (1): 41-45.

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[18] Wang S, Almehmi A, Asif A. Surgical management of cephalic arch occlusive

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lesions: are there predictors for outcomes? Semin Dial. 2013;26(4): E33-E41.

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[19] Fillinger MF, Reinitz ER, Schwartz RA, et al. Beneficial effects of banding on

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venous intimal-medial hyperplasia in arteriovenous loop grafts. Am J Surg 1989;

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158:87-94.

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[20] Miller GA, Friedman A, Khariton A, Peddie DC, Savranky Y. Access flow

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reduction and recurrent symptomatic cephalic arch stenosis in brachiocephalic

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hemodialysis arteriovenous arteriovenous fistulas. J Vasc Access. 2010; 11(4): 281-287.

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ACCEPTED MANUSCRIPT 7- TABLES

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349 Table I. Demographic and clinical characteristics

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AVF

AVF

Cephalic arch

(M/F)

(Y/N)

type

duration (y)

problem

F

Y

BC

3

CAS

2

59

F

Y

BC

1

CAS

3

81

M

N

BC

7

CAS

70

F

Y

BC

5

79

M

N

BC

6

61

F

Y

BC

77

F

Y

BC

3

CAS

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VV with vein transposition VV with vein transposition Thrombectomy + VV with

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Surgical procedure

vein transposition

VV with vein transposition

1

entrapment

VV with vein transposition

5

CAS, high-

VV with vein transposition

flow

+ cephalic plication

tortuosity

VV with vein transposition

5

M-Male, F-Female, Y-Yes, N-No, AVF-arteriovenous fistula, BC-brachiocephalic, CAS-cephalic arch stenosis, y-years, VV-venovenostomy

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Diabetes

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Gender

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Age

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Table II. AVF endovascular intervention and thrombosis rates Before surgery

After surgery

Endovascular intervention rate

1.9/patient/year

0.4/patient/year

p<0.05

Thrombosis rate

0.93/patient/year

0.17/patient/year

p<0.05

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AVF- arteriovenous fistula

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Table III. Problems leading to endovascular reintervention after surgery (n=7)

new venous anastomosis stenosis

5 (57%)

axillary vein stenosis

2 (29%)

swing-point stenosis

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1 (14%)

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8- LEGENDS TO FIGURES

401 Figure 1-approaching and isolating cephalic and axillary veins

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Figure 2-marking the cephalic vein to avoid rotation

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Figure 3-tunneling the cephalic vein to the axillary vein with a specific tunneler

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Figure 4- final result after sutures

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