Access Flow Based Intervention for Management of Arteriovenous Hemodialysis Access Dysfunction.

Summary

Hemodialysis (HD) vascular access dysfunction is a huge clinical problem which results in significant clinical morbidity in patients with End Stage Renal Disease (ESRD), causing a severe economic burden on any health care system. Arteriovenous (A-V) dialysis accesses are the preferred form of permanent dialysis access as compared to central venous catheters (CVC) . One of the reasons for CVC use is poor long term patency rates of A-V access. Arteriovenous Grafts (AVG) have a primary patency rates of just under 50% at 12 months and around 33% at 18 months. Native arteriovenous fistula (AVF) are slightly better with primary patency rates of around 60 percent at one year and 51 percent at 2 years. The most common cause for AVF and AVG dysfunction is stenosis development due to neointimal hyperplasia (NIH) within the circuit leading to access thrombosis. Percutaneous transluminal angioplasty (PTA) is the current standard of treatment for these lesions. Despite being the treatment of choice for these lesions patency rates after PTA continue to be dismal. One of the problems with poor long term outcomes after successful intervention is how you assess immediate intervention success. Successful angioplasty is defined by Dialysis Outcome Quality Initiative (DOQI) guidelines as one where only less than 30% residual stenosis remains at the end of intervention. Unfortunately angiographic images post angioplasty correlate poorly with improvement of access flows through the arteriovenous circuit. There are two main problems with these practice standards. First, they are based on a 2-dimensional angiographic view of the lesion which may be misleading. Secondly, this assessment of recoil is very subjective and not base on objective data.

Access flow monitoring can now be performed intra-procedurally with thermal dilution technique. Its benefit was shown in a small pilot study. To date there have not been any randomized controlled trials to assess the benefit of such an approach where intervention is based on improvements in access flow at the time of intervention. We hypothesize that such an approach will improve outcomes after interventions related to access dysfunction. This may also identify the right scenarios in which stent placement may benefit thus improving outcomes after stent placement as well.

Conditions

• Hemodialysis Arteriovenous Fistula Maturation Failure

Interventions

PROCEDURE

Intra-procedural access flow

Intra-procedure access flow technique: Room temperature saline is injected into the vascular access blood stream during angioplasty via ReoCath(tm) 6 French antegrade or retrograde flow catheters. When the saline is injected into the access, an injection thermistor located close to the proximal end of the catheter records the temperature of the injected saline. A second thermistor located close to the distal tip of the catheter then records the thermodilution within the access and the HVT100 endovascular flow meter calculates and displays intragraft blood flow in ml/min.

PROCEDURE

Standard Angioplasty

Intervention based on 2 Dimensional fluoroscopy views

Sponsors & Collaborators

• King Faisal Specialist Hospital & Research Center

  lead OTHER

Principal Investigators

• Naveed U Haq, MD, FASN · King Faisal Specialist Hospital & Research Center

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2015-10-31

Primary Completion

2018-10-31

Completion

2018-10-31

Countries

• Saudi Arabia

Study Locations