PREDICTING VASCULAR ACCESS ANGIOPLASTY SUCCESS OR FAILURE WITH A DIGITAL STETHOSCOPE

Introduction:

Arteriovenous fistula (AVF) and arteriovenous graft (AVG) dysfunction, often as a result of a venous segment stenosis is a common cause of vascular access dysfunction that is most commonly treated with an endovascular procedure (angioplasty +/- stent placement). Although vascular access dysfunction results in a very significant morbidity, mortality and economic cost, the results of angioplasty in particular remain sub-optimal, with a 50-60% post-intervention unassisted primary patency rate at 6 months. Most importantly, we have no good tools to assess the likelihood of angioplasty success or failure at a clinical level. We herein present data on on pre- and post-angioplasty phonocardiograms using the Eko digital stethoscope as a possible way to risk stratify patients following Endovascular intervention for vascular access stenosis.

Methods:

We used physical examination to identify the site of the arteriovenous or graft vein anastomosis. The Eko Littman® CORE Digital Stethoscope and Eko smartphone app were used to obtain phonocardiogram recordings from three sites associated with the AVF: distal venous (8cm distal to the anastomosis and towards the heart), proximal arterial (2cm proximal to the anastomosis), and distal arterial (2cm distal to the anastomosis. AVG recordings were obtained 2 cm proximal to the graft-vein anastomosis (over the graft) and 8cms distal to the anastomosis (towards the heart). All recordings were obtained both immediately prior to and following endovascular intervention. De-identified recordings were labeled by location and exported prior to analysis.

Results:

We observed differences in both the amplitude and profile (Fig. 1) of phonocardiogram recordings taken at the same site before and after endovascular intervention. 

Conclusions:

1. We have demonstrated the technical feasibility of using a portable, user-friendly, digital stethoscope and smartphone app. in the setting of dialysis vascular access dysfunction. 2. Clear differences in both the amplitude and profile of phonocardiograms suggest that the Eko device could be used to risk stratify patients at high risk of a failed angioplasty. 3. The Eko phonocardiograms could be an effective, low cost screening tool for angioplasty success or failure in the setting of dialysis vascular access dysfunction. This would allow for a future more individualized process of care for patients with vascular access dysfunction.  

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.