Endothelial Function and Arterio-Venous Fistula Maturation (EFAVF)

• Maturation of Arteriovenous Fistula [ Time Frame: 90 days ]

  Maturation is defined by either:

  • Less than three months have elapsed since AVF creation and cannulation of the fistual with two 17 gauge needles and delivery of a minimum of 400 ml/min for the duration of dialysis
  • Greater than three months have elapsed since AVF creation and the individual has not yet initiated hemodialysis and the vein diameter is 4 mm and the volumetric flow rate is 400 ml/min.
  
  

• Primary Patency [ Time Frame: 90 days ]
  Primary patency of the AV fistula
  
  
• Secondary Patency [ Time Frame: 90 days ]
  Secondary patency of the AV fistula
  
  
• Stenosis of AV fistula [ Time Frame: 90 days ]
  Moderate or severe stenosos of AV fistual as detected by duplex ultrasound or fistulagram
  
  
• Venous remodeling [ Time Frame: 90 days ]
  Venous remodeling at 3 months
  
  
• Arterial remodeling [ Time Frame: 90 days ]
  Arterial remodeling at 3 months
  
  

Current practice guidelines stipulate that 65% of all prevalent ESRD patients should receive HD through some sort of arterio-venous fistula (AVF). An AVF is a subcutaneous, permanent vascular access created surgically by connecting a vein with an artery and is the preferred mode of access due to lower rates of infection or thrombosis compared to prosthetic grafts or tunneled lines. An AVF is mature if it can sustain high quality HD. However, rates of primary failure (the inability of an AVF to sustain HD) are high, ranging from 40-70%. Traditional coronary risk factors such as hypertension, hypercholesterolemia, and diabetes mellitus, have limited ability to allow surgeons to predict which AVFs will mature.

One possible explanation involves vascular remodeling, the structural changes which occur in a blood vessel in response to hemodynamic stimuli. The endothelial, lying at the interface of the vessel wall and flowing blood, is a "biosensor", responding to changes in blood flow and pressure. It initiates a complex biological response including cellular proliferation and migration, matrix degradation, and cellular apoptosis. This longitudinal, observational study hypothesizes that endothelial function is a critical modulator of AVF maturation. Specifically, that patients with inflammation will have impaired endothelial function and demonstrate less significant remodeling than others.