CEUS-guided PTA on stenotic AVF: Morphological and functional point of view

Abstract

Background: Stenosis represents the main cause of hemodialysis fistula malfunction. The ultrasound-guided angioplasty with ecographic contrast (CEUS) could provide further advantages to the classical ultrasound guided method improving the morphological characterization of the stenosis and providing quantitative data with the creation of time intensity curves (TIC) collecting functional data comparable between pre and post procedure. Methods: A total of 10 CEUS-guided angioplasties were performed on malfunctioning fistulas. The sonographic contrast medium was injected into the vascular tree trough the introducer. Morphological and functional data nature were collected. Were generated TIC curves, obtained by positioning a ROI in correspondence with the post-stenotic tract of the efferent vein. The data collected, regarding the peak intensity reached by the signal (PI) and the time to reach the peak signal intensity (TTP), were compared in the pre and post-procedural phase with flow of vascular access (Qa) and resistance indices (RI). Results: Statistically significant correlation ( p < 0.05) was observed between Qa and TTP ( r = 0.77; p = 0.009), RI and TTP ( r = 0.71; p = 0.02), Qa and PI ( r = 0.86; p = 0.0012), and between RI and PI ( r = 0.88; p < 0.001). Conclusion: In addition to the advantages associated with the use of ultrasound contrast medium in improving the visualization and characterization of the stenosis by facilitating the PTA procedure, the functional data deriving from the quantitative analysis provide new parameters for evaluating the success of the procedure which could also be used as predictive markers of stenosis recurrence together with the classical ones.

The Use of Ultrasound Contrast in Interventional Radiology

“…Similarly to angioplasty the angiographic nature means CEUS can guide intervention in hemodialysis fistulas and detect complications such as rupture. 40 Reinjection can be performed as required given the absence of nephrotoxicity and excellent safety profile.…”

Risk factors for blood vessel rupture during vascular access intervention therapy for hemodialysis patients

“…According to the guidelines for VAIVT from the Japan and Kidney Disease Outcomes Quality Initiative (KDOQI) [14][15][16], assessment of the brachial artery resistance index is useful for predicting primary patency rate after creating AVF and for the detection of AVF dysfunction. The optimal resistance index threshold for insufficient blood flow was 0.61 in patients with AVF and 0.57 in patients with AVG [17].…”