title: Does pre- and post-angioplasty Doppler ultrasound evaluation help in predicting vascular access outcome?
abstract: BACKGROUND
  Kidney Disease - Improving Global Outcomes (KDIGO) recommends post-percutaneous transluminal angioplasty (PTA) <30% residual stenosis (RS) and hemodynamic parameters improvement. Primary end point: how post-PTA access blood flow (ABF) improvement predicts vascular access (VA) outcome. Secondary: compare Doppler ultrasound (DU) and angiography diagnostic accuracy; determine how other factors predict outcome.
  
  
  METHODS
  Eighty patients. DU evaluation performed pre- and post-PTA. Several parameters recorded. Secondary patency verified after 6 months.
  
  
  RESULTS
  Initial ABF 537 ± 248 mL/min; final ABF 1013 ± 354 mL/min. Number and location of stenosis was highly correlated between DU and angiography (p<0.001); central vessels mismatching. First semester overall survival was 63%; significantly better for fistulas (76%) than grafts (51.7%), p 0.044. Final RS>30% associated to better survival, p 0.038. Initial ABF<500 mL/min and multiple stenosis did not affect outcome (p>0.05). A >2-fold ABF increase had no significant impact on fistulas (p>0.05) but was significantly associated with worst outcomes in grafts (23.1% vs. 73.5%, p 0.009). Grafts had lower survival (HR 3.3, p 0.034).
  
  
  CONCLUSIONS
  Although less accurate for central lesions, DU has a key role on VA surveillance, allowing a morphologic and hemodynamic assessment. Angioplasty is effective in preserving VA; however, it may increase restenosis due to accelerated neointimal hyperplasia. Current parameters are not useful. Trials addressing this issue are needed.
authors.affiliation: Vascular Access Center of Nephrocare Lumiar, Lisbon - Portugal.
authors.forename: Maria
authors.initials: M
authors.lastname: Guedes-Marques
authors.affiliation: Vascular Access Center of Nephrocare Coimbra, Coimbra - Portugal.
authors.forename: Pedro A
authors.initials: PA
authors.lastname: Maia
authors.affiliation: Vascular Access Center of Nephrocare Lumiar, Lisbon - Portugal.
authors.forename: Fernando
authors.initials: F
authors.lastname: Neves
authors.affiliation: Vascular Access Center of Nephrocare Lumiar, Lisbon - Portugal.
authors.forename: Aníbal
authors.initials: A
authors.lastname: Ferreira
authors.affiliation: Vascular Access Center of Nephrocare Lumiar, Lisbon - Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Cruz
authors.affiliation: Vascular Access Center of Nephrocare Lumiar, Lisbon - Portugal.
authors.forename: Dulce
authors.initials: D
authors.lastname: Carvalho
authors.affiliation: Vascular Access Center of Nephrocare Lumiar, Lisbon - Portugal.
authors.forename: Carlos
authors.initials: C
authors.lastname: Oliveira
authors.affiliation: Vascular Access Center of Nephrocare Lumiar, Lisbon - Portugal.
authors.forename: Carlos
authors.initials: C
authors.lastname: Barreto
authors.affiliation: Vascular Access Center of Nephrocare Lumiar, Lisbon - Portugal.
authors.forename: Telmo
authors.initials: T
authors.lastname: Carvalho
authors.affiliation: Vascular Access Center of Nephrocare Lumiar, Lisbon - Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Ponce
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography; D000800:Angioplasty, Balloon / Q000009:adverse effects; D001166:Arteriovenous Shunt, Surgical / Q000009:adverse effects*; D001783:Blood Flow Velocity; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects*; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D058426:Neointima; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012008:Recurrence; D012039:Regional Blood Flow; D006435:Renal Dialysis; D019233:Retreatment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler; D014654:Vascular Patency