title: Utility of static pressure ratio recording during angioplasty of arteriovenous graft stenosis.
abstract: Intra-access static pressure ratio (SPR) (intra-access pressure/mean arterial pressure) can be measured during angioplasty (PTA) to assess the functional importance of an arteriovenous graft (AVG) stenosis. We used SPR in 70 patients with AVGs who underwent 98 angioplasty procedures. SPR was measured during angioplasty by placing a catheter tip at mid-access. Inflow stenosis (IF) = stenosis proximal to the tip of the catheter. Outflow stenosis (OF) = stenosis distal to the tip of the catheter up to the superior vena cava-atrial junction. Post PTA, access flow (Qa) was assessed within 2 weeks. Complete data sets for both SPR and Qa were available in 83 procedures. Using a normal SPR ratio of 0.3-0.4 at mid-graft, three patterns of SPR were noted. In 63 of 83 (76%) cases SPR was elevated prior to PTA (0.71 +/- 0.13 SD). PTA reduced SPR toward normal range (0.44 +/- 0.12) in 53 cases (84%). In the remaining 10 (16%), SPR decreased to a low value (0.22 +/- 0.03) and normalized (0.40 +/- .0.11) only after PTA of a coexisting inflow stenosis. In 12 of 83 (14%) procedures, the initial SPR was low (0.18 +/- 0.04) and increased toward normal (0.3 +/- 0.08) following IF stenosis PTA in seven (58%) cases. For the remaining five (42%) cases SPR increased to a high value (0.70 +/- 0.21) and decreased toward normal range (0.33 +/- 0.07) only after OF stenosis angioplasty. In 8 of 83 (10%) procedures, initial SPR was normal (0.33 +/- 0.02). Angiography revealed coexisting IF and OF stenoses. SPR remained within the normal range after PTA of these lesions (0.33 +/- 0.02). Qa increased significantly in 74 of 83 (89%) procedures (before = 572 +/- 201, after = 1109 +/- 368 ml/min; p < 0.001). SPR measurements can assist in hemodynamic assessment of an AVG during angioplasty procedure.
authors.affiliation: Division of Nephrology, Department of Medicine, University of Miami School of Medicine, Miami, Florida, USA.
authors.forename: Arif
authors.initials: A
authors.lastname: Asif
authors.forename: Anatole
authors.initials: A
authors.lastname: Besarab
authors.forename: Florin
authors.initials: F
authors.lastname: Gadalean
authors.forename: Donna
authors.initials: D
authors.lastname: Merrill
authors.forename: Anne E
authors.initials: AE
authors.lastname: Rismeyer
authors.forename: Gabriel
authors.initials: G
authors.lastname: Contreras
authors.forename: Baudouin
authors.initials: B
authors.lastname: Leclercq
authors.forename: Oliver
authors.initials: O
authors.lastname: Lenz
authors.forename: Jeffery
authors.initials: J
authors.lastname: Wallach
authors.forename: Joshua
authors.initials: J
authors.lastname: Wallach
authors.forename: Michael I
authors.initials: MI
authors.lastname: Levine
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D015901:Angiography, Digital Subtraction; D000800:Angioplasty, Balloon; D001166:Arteriovenous Shunt, Surgical / Q000009:adverse effects*; D001794:Blood Pressure; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D012079:Renal Circulation; D006435:Renal Dialysis; D012107:Research Design; D016896:Treatment Outcome; D014654:Vascular Patency