For Old or Young Dialysis Patients, AV Fistulas Remain Pure Gold

Andrew R. Forauer, MD

Michael Bazylewicz, BS

Kristine A. Pattin, BS

Interventional RadiologyDartmouth-Hitchcock Medical Center

Lebanon, NH

Scope of the problem

• End-stage kidney disease effects hundreds of thousands of U.S. patients

• Approximately 400,000 require hemodialysis

• 20 % of those on dialysis are age 75 or older • That’s 1 out of 5 patients !

When your kidneys don’t work

• Kidneys filter the blood & remove harmful substances

• When they don’t work properly, the toxins accumulate, & patients become ill

• They will require :– an artificial form of blood filtering (=DIALYSIS)– kidney transplant

Dialysis 101

• This requires removing blood, filtering it, and returning it the patient

Dialysis 101

• This filtering can be accomplished by creating a connection between an artery & a vein, typically in the arm.

• Termed an ARTERIOVENOUS (AV) access

• The preferred method uses the patient’s own veins to create this connection (=an AV fistula)

Connection of the vein to the artery

The flow of blood is indicated by the arrows () from the artery, into the fistula & back to the heart.

artery

Fistula (vein)

Left upper arm AV fistula

• Unfortunately, narrowings develop in these AV fistulas over time

• Reducing blood flow through them

• Making dialysis less efficient

• Requires a medical procedure to correct

• Interventional Radiologists can identify these narrowings, position a balloon catheter , & dilate them (Angioplasty)

Misconception: The elderly patient does not do well when they require dialysis

• Why wouldn’t the way we provide dialysis be the same for younger vs. older patients?

• The elderly may have more chronic medical conditions & be receiving more medications

• But do these factors effect the patient’s AV access ?

Goals

• Does balloon dilation (angioplasty) of dialysis fistulas in elderly patients work the same, better, or worse compared to younger patients ?

• Are the patency rates (how long these fistulas remained open) in older patients to a younger patients the same ?

Comparing the two groups

Patients aged 75 yrs & older

Younger patients (age 40 – 60 yrs)

Number of patients 38 36

Average age(years)

80.0 52.9

Time on dialysis(days)

120 360

Co-existing medical conditions

Patients aged 75 yrs & older

Younger patients (age 40 – 60 yrs)

Diabetes 17 24

High blood pressure

30 27

Heart disease or atherosclerosis

28 15

Heart function(% EF)

52% 63%

Our Findings…

• Heart or vascular disease, the time spent on dialysis & medications had no influence on two important aspects:

1. how long the access stayed open

2. response to angioplasty to keep them open

How well did angioplasty work in keeping the access open ?

• Older patients (75 years & older):– 200.2 days (6.7 months)

• Patients age 40 – 60 years:– 211.5 days (7 months)

• No significant difference

Summary

• Our results support:

– creating AV fistulas for dialysis in older patients; this is the preferred route for treatment

– the key role Interventional Radiology plays in

keeping them open and functioning properly

• Older patient age alone should not be viewed as limiting the patient’s access options