Balloon-Assisted Maturation of Autogenous Arteriovenous Fistulae; Clinical Efficacy and Complications: Randomized Prospective Study

INTRODUCTION:

End-stage renal disease (ESRD) is the crossing point of multiple heterogeneous disease pathways that can alter the structure and function of the kidneys irreversibly. Both definition and classification of ESRD have been developing over time. However, current international guidelines define ESRD as declined kidney function shown by GFR of less than 60 mL/min per 1•73 m², kidney damage markers or both, for at least 3 months duration, regardless of underlying cause.1 Haemodialysis (HD) is a lifeline management for patients with ESRD. A critical factor in the survival of renal dialysis patients is the surgical creation of vascular access, and international guidelines recommend arteriovenous fistulas (AVF) as the gold standard vascular access for haemodialysis. Arteriovenous graft and central vein catheters have higher primary patency rates compared to AVF, however native AVFs last longer. 3 There is conflicting evidence about the impact of various demographic characteristics of the patients on the functional maturation of the native AVFs. Certain characteristics such as diabetes mellitus, female gender, thrombophilia and various hematological factors, such as platelet count and hemoglobin levels, can affect fistula maturation. Also the impact of certain operative and anatomical factors, including but not limited to diameter of artery and venous limb of the AVF, presence of palpable thrill, audible bruit, and anatomical site of fistula may affect outcome.4 Functional fistula maturation is defined as patent fistula, ready for cannulation with vein length of at least 10 cm long segment, diameter more than 6 mm, depth not more than 6 mm and ability of the access to deliver a flow rate of 350 to 400 ml/min and maintain dialysis for 3.5 to 4 hours.5 Delayed maturation of AVF among patients who require hemodialysis can lead to catheter sepsis with its resultant morbidity and mortality. Some authors have proposed that sequential BAM may accelerate maturation process and shorten the maturation times of these accesses.6 Balloon angioplasty maturation is emerging as a surgical technique that could increase utilization and improve function of autogenous arteriovenous hemodialysis accesses. This approach includes primary balloon angioplasty (PBA) of small veins during AVF creation.9-10 However there are no studies that directly compare maturation times for AVF with and without using BAM. There are several studies that document the safety and efficacy of the BAM technique. 7 Ultimately, there are also studies that report its possible negative consequences such as fibrosis and restenosis of venous outflow, leading to malfunctioning AVF. 8 Thus, in an effort to increase the number of primary AVFs, shorten maturation times, and reduce the number of indwelling catheters, we ascertain the BAM technique within this study to optimize access care and maximize use of AVFs.

Patients and Methods:

This is a randomized prospective study conducted in the department of vascular surgery, Mansoura university hospitals. Between July 2017 and May 2019 Three hundred patients were recruited from a total of 648 primary AVF creation cases. Patients had been advised to undergo elective surgery for AVF once their renal glomerular filtration rate estimated (eGFR) is less than 15 ml/min. Block randomization was the method used for stratification of patients' groups.

Inclusion and exclusion criteria: All patients aged 18 years or older who need AVF formation in the upper limb were included as a recruitment target. In patients with multiple episodes of AVF creation, each episode was considered separately and data from the corresponding episode had been recorded in our data sheet. Patients who underwent salvage procedures to improve maturation, i.e. secondary maturation, or those who could not give informed consent were not included1. A total of 335 patients who needed Autogenous AVF were enrolled in the study during that period.