Long-term effects of arteriovenous fistula closure on echocardiographic function

[okarol]

Am J Kidney Dis. 2010 Apr;55(4):682-9. Epub 2010 Jan 20.
Long-term effects of arteriovenous fistula closure on echocardiographic functional and structural findings in hemodialysis patients: a prospective study.

Movilli E, Viola BF, Brunori G, Gaggia P, Camerini C, Zubani R, Berlinghieri N, Cancarini G.

Division of Nephrology, Spedali Civili, and Section of Nephrology, University of Brescia, Brescia, Italy. eziomov@libero.it
Abstract

BACKGROUND: The arteriovenous fistula (AVF) provides an effective vascular access for hemodialysis; however, the associated hemodynamic effects may alter cardiac structure and function. The objective of this study is to evaluate the effect of AVF closure on functional and structural echocardiographic findings. STUDY DESIGN: Prospective observational study. SETTING & PARTICIPANTS: In a single center between 2003 and 2006, we enrolled 25 consecutive hemodialysis patients with AVF malfunction who underwent AVF closure and conversion to a tunneled central venous catheter because of exhaustion of alternative vascular sites and 36 matched controls with a well-functioning AVF. PREDICTOR: AVF closure. OUTCOMES & MEASUREMENTS: Outcomes were changes in findings on echocardiograms obtained before and 6 months after AVF closure for patients in the AVF-closure group and at baseline and 6 months later for controls. Echocardiographic measurements included left ventricular (LV) internal diastolic diameter, interventricular septum thickness, diastolic posterior wall thickness, LV mass (LVM), LVM index (LVMi), and LV ejection fraction (LVEF). Dialysis modality and scheme were unchanged. RESULTS: In the AVF-closure group, LVM decreased from 225 +/- 55 to 206 +/- 51 g (P < 0.001) and LVMi decreased from 135 +/- 40 to 123 +/- 35 g/m(2) (P < 0.001). LV internal diastolic diameter, interventricular septum thickness, and diastolic posterior wall thickness decreased significantly, whereas LVEF increased from 56% +/- 7% to 59% +/- 6% (P < 0.001). No significant changes were observed in controls. In patients with AVF closure, LV morphologic characteristics showed a decrease in both eccentric and concentric hypertrophy in favor of normalization or a pattern of concentric remodeling. No significant changes were observed in controls. LIMITATIONS: Use of matched rather than randomized controls. CONCLUSIONS: Closure of an AVF determines a significant decrease in LV internal diastolic diameter, interventricular septum thickness, and diastolic posterior wall thickness. This is associated with significant improvement in LVEF, a significant decrease in LVM and LVMi, and a more favorable shift of cardiac geometry toward normality. Copyright 2010 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

PMID: 20089339 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/20089339

[Sunny]

Given this study, why don't they close off AV Fistulas after transplants?

[jbeany]

It's too new of a study to have any effect on standard protocol, most likely.  I think most accesses fail shortly after transplant, anyhow.

[Meinuk]

Oh, this I know about.... Sadly.

When a fistula is created, there is increased bloodflow where there should not be increased blood flow.  In the case of my up arm AV fistula, my body naturally tried to close it off (stop the high blood flow) by creating a subclavian stenosis.  When I was on dialysis, I has a fistulagram and angioplasty every three months.  (and after angioplasty, scar tissue builds up - it is a vicious cycle)  My body was trying to correct the fistula. I blame my viking ancestors, always battling to survive no matter what.

When I had my pre-transplant angiogram there was a thickening of my left ventricle (which is common in people with fistulas). Long long term, that could be a cardiac issue, but dialysis wise, not a problem.  Staying alive is a priority.

A good fistula won't fail after transplant.  The protocol is to tie them off one year post transplant to protect cardiac status.  I wanted to keep mine, but my aneurysm is forcing me to have the whole vein removed.

Dialysis is so efficient nowadays, people usually last for years, and then cardiac/circulatory issues get them in the end.  Anti rejection drugs are so good nowadays, people can usually plan on 10 years for a deceased donor kidney, so it would be in the best cardiac interest to tie off a fistula for less stress on the cardio vascular system.  I was willing to risk it and keep my access.  But my body said no.

[monrein]

I plan to raise this issue with my neph at our next appointment.  My first one clotted off a year post-transplant.  This second one in my upper arm seems to have a mind and life all its own...we'll see what they think.

[okarol]

I had never heard this before. I always thought that transplant patients kept their fistulas working as long as possible. When Jenna's clotted on the day of her transplant, I had no idea that it was probably good for her heart.