title: Evaluating the need for and effect of percutaneous transluminal angioplasty on arteriovenous fistulas by using total recirculation rate per dialysis session ("clearance gap").
abstract: The functioning of an arteriovenous fistula (AVF) used for vascular access during hemodialysis has been assessed mainly by dilution methods. Although these techniques indicate the immediate recirculation rate, the results obtained may not correlate with Kt/V. In contrast, the clearance gap (CL-Gap) method provides the total recirculation rate per dialysis session and correlates well with Kt/V. We assessed the correlation between Kt/V and CL-Gap as well as the change in radial artery (RA) blood flow speed in the fistula before percutaneous transluminal angioplasty (PTA) in 45 patients undergoing continuous hemodialysis. The dialysis dose during the determination of CL-Gap was 1.2 to 1.4 Kt/V. Patients with a 10% elevation or more than a 10% relative increase in CL-Gap underwent PTA (n = 45), and the values obtained for Kt/V and CL-Gap before PTA were compared with those obtained immediately afterward. The mean RA blood flow speed improved significantly (from 52.9 to 97.5cm/sec) after PTA, as did Kt/V (1.07 to 1.30) and CL-Gap (14.1% to -0.2%). A significant correlation between these differences was apparent (r = -0.436 and p = 0.003). These findings suggest that calculating CL-Gap may be useful for determining when PTA is required and for assessing the effectiveness of PTA, toward obtaining better dialysis.
authors.affiliation: Department of Emergency Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan. ugawat@md.okayama-u.ac.jp
authors.forename: Toyomu
authors.initials: T
authors.lastname: Ugawa
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Sakurama
authors.forename: Takashi
authors.initials: T
authors.lastname: Yorifuji
authors.forename: Munenori
authors.initials: M
authors.lastname: Takaoka
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Fujiwara
authors.forename: Narutoshi
authors.initials: N
authors.lastname: Kabashima
authors.forename: Daisuke
authors.initials: D
authors.lastname: Azuma
authors.forename: Takahiro
authors.initials: T
authors.lastname: Hirayama
authors.forename: Kohei
authors.initials: K
authors.lastname: Tsukahara
authors.forename: Sunao
authors.initials: S
authors.lastname: Morisada
authors.forename: Atsuyoshi
authors.initials: A
authors.lastname: Iida
authors.forename: Keitaro
authors.initials: K
authors.lastname: Tada
authors.forename: Naoki
authors.initials: N
authors.lastname: Shiba
authors.forename: Nobuo
authors.initials: N
authors.lastname: Sato
authors.forename: Shingo
authors.initials: S
authors.lastname: Ichiba
authors.forename: Koichi
authors.initials: K
authors.lastname: Kino
authors.forename: Masaki
authors.initials: M
authors.lastname: Fukushima
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Ujike
mesh_terms: D000368:Aged; D017130:Angioplasty; D001164:Arteriovenous Fistula / Q000628:therapy*; D001783:Blood Flow Velocity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017534:Radial Artery / Q000503:physiopathology*; D006435:Renal Dialysis / Q000379:methods*