Early Detection of Hemodialysis Ateriovenous Fistula Dysfunction by Trend Analysis of Intra-access Pressure

Ahn, Hyung Joon; Lee, Jong Hoon; Park, Sung Il; Yoon, Soo Young; Lee, Sang Choel; Yang, Sung Ja; Kim, Yu Seun; Park, Kiil

Abstract

PURPOSE: To detect early arteriovenous fistula (AVF) dysfunction, we have developed a new method of intra-access total pressure (pT), and static pressure (pS) measurements. The purpose of this study is to assess the relationship between intra-access pressure and vascular stricture in order to establish the clinical validity of the method.
METHODS
Total 46 of native AVFs were enrolled. They were measured intra-access pS and pT monthly. In initial angiography, 6 of 10 inflow stricture (As), 6 of 7 outflow stricture (Vs) and 2 having both lesions were taken PTA (percutaneous angioplasty) and compared pressure and ratio changes. If delta p (pT-pS) decreased more than 10% over 3 months or pT/MAP (mean arterial pressure) ratio dropped more than 10% over 3 months with below 0.8, then the patients were referred to angiography. Thirtyone patients were performed final angiography, and we compared the results with those of initial angiography.
RESULTS
Although pT/MAP ratio and delta p were increased after PTA, there was no statistical significance in 6 As (+) patients (p>0.05). Six Vs (+) and 2 AS (+) and Vs (+) patients' delta p were increased significantly (p<0.05). Two As (+) and 5 Vs (+) were detected with delta p or pT/MAP ratio change. However, 2 Vs (+) were unable to be detected with delta p, but detected only by final angiography. Among 15 As (-) and Vs (-) patients in both initial and final angiography, pT and MAP were not reproducible (pI<0.4), but pS and delta p showed intermediate reproducibility (pI>0.45).
CONCLUSION
Intra-access stricture could be detected with pT/MAP ratio and delta p change. However, more careful MAP and pT measurement should be recommended for accurate diagnosis.