# Long-Term Arteriovenous Access Clinical Patency Following Successful Thrombolysis: A Single-Centre Experience

## TL;DR

This study examines the long-term effectiveness of thrombolysis in restoring dialysis access, finding that while it works initially, the benefits don't last.

## Contribution

The study provides new clinical insights into the long-term outcomes of thrombolysis for dialysis access, emphasizing the need for proactive management strategies.

## Key findings

- Clinical patency rates after successful thrombolysis decline significantly over time, with only 7.9% remaining patent after three years.
- AV grafts are more likely to re-thrombose after successful thrombolysis compared to AV fistulas.
- Endovascular strategies allow continued hemodialysis but do not improve overall access survival.

## Abstract

Introduction

There is a paucity of data regarding the long-term outcomes following thrombolysis of arteriovenous (AV) access for dialysis. The aim was to determine the technical and clinical success following thrombolysis of a thrombosed AV access and the long-term clinical patency and access survival in our institution.

Methods

Retrospective identification of all patients undergoing thrombolysis of an AV access, AV fistula (AVF), or graft (AVG) over eight years at a single institution. Patient characteristics, access type, type of thrombolysis, and fistula life were recorded. Data were censored for death, transplantation, and loss to follow-up.

Results

Ninety-eight vascular accesses (79 AVF and 19 AVG) in 94 patients underwent thrombolysis during the study period. Fifty-three (56.4%) were male with a median (interquartile range [IQR]) age of 66 (53-74) years. Immediate technical and clinical success were 82% and 75%, respectively. Clinical patency following clinically successful thrombolysis at three, six, and 12 months was 64.5%, 60%, and 45.9%, respectively. At two and three years, clinical patency was 21.3% and 7.9%, respectively. AVFs were older than AVGs, 96 (44-192) vs. 20 (12-76) months, p<0.0001 at the time of thrombolysis. 21% of AV accesses that had successful thrombolysis and restoration of clinical patency re-presented with thrombosis after a median (IQR) of 185 (93.5-358) days and underwent further thrombolysis. AVGs (47.4%) were more likely to have re-thrombosed after successful thrombolysis than AVFs (15.2%), p=0.002. Kaplan-Meier survival analysis demonstrated that AVFs remained patent for longer than AV grafts (p=0.023) following successful thrombolysis. While in the short term, clinical patency was re-established, overall, there was no AV access survival advantage (p=0.085) over those that only required one episode of thrombolysis to restore access patency.

Conclusions

Endovascular strategies for dealing with thrombosed access are clinically important in allowing haemodialysis to continue. However, the clinical patency rates, while good in the short term, fail to be sustained long term. We propose that an episode of AV access thrombosis and successful thrombolysis should prompt a review of previous access-related interventions, age of AV access, and planning for alternative AV access options, be it new AV access formation, transplant, or long-term catheter placement.