title: Economic impact of an ultrasonographic contrast agent on the diagnosis and initial management of patients with suspected renal artery stenosis.
abstract: OBJECTIVE
  To determine resource use in the diagnosis and management of Canadian hypertensive patients with suspected renal artery stenosis and to estimate the impact of diagnosis with contrast-enhanced duplex Doppler ultrasonography (US) on resource use.
  
  
  METHODS
  Seventy-eight patients with suspected renal artery stenosis underwent usual diagnostic tests (captopril-enhanced renal scintigraphy or duplex Doppler US) and contrast-enhanced US. A management pathway ("planned") describing the medical resources required for further patient care was outlined on the basis of results from each test (separately), and a modified management pathway ("recommended"), which considered data from both diagnostic methods, was also outlined. Medical resources and productivity losses were assessed prospectively for a 3-month period after patients underwent both tests ("actual" management pathway).
  
  
  RESULTS
  With usual diagnostic methods, 14 (18%) of the tests were inconclusive, whereas only 1 (1%) of the enhanced US examinations was inconclusive; the cost-efficacy ratio was $422 and $343 per successful diagnosis, respectively. Further management costs for patients with an inconclusive diagnosis were estimated at $6370 after the usual diagnostic tests, but only $1278 with enhanced US. Although the costs of the planned and recommended management pathways were similar ($227 and $294 per patient respectively), the proportion of patients requiring further resources was lower with enhanced US (56% v. 46%). Three-month actual management costs ranged from $121 to $1605 per patient (mean $360). Diagnostic tests and surgical procedures were the major cost drivers in all pathways, and costs were highest for patients in whom stenosis was diagnosed.
  
  
  CONCLUSIONS
  For patients with suspected renal artery stenosis, contrast-enhanced US had a higher diagnostic success rate than usual diagnostic methods and afforded savings through lower administrative costs and lower medical resource consumption for patients whose diagnosis was unclear after usual diagnostic tests.
authors.affiliation: Centre hospitalier de l'Université du Québec. jacques.levesque@chuq.qc.ca
authors.forename: Jacques
authors.initials: J
authors.lastname: Lévesque
authors.forename: Yves
authors.initials: Y
authors.lastname: Lacourcière
authors.forename: John M
authors.initials: JM
authors.lastname: Onrot
authors.forename: Stephanie R
authors.initials: SR
authors.lastname: Wilson
authors.forename: Esther
authors.initials: E
authors.lastname: Szaky
authors.forename: Micheline
authors.initials: M
authors.lastname: Thibodeau
authors.forename: Murray L
authors.initials: ML
authors.lastname: Vasilevsky
authors.forename: Sidney M
authors.initials: SM
authors.lastname: Dashefsky
authors.forename: Donald R
authors.initials: DR
authors.lastname: Allan
authors.forename: Michel
authors.initials: M
authors.lastname: Lafortune
authors.forename: Benoît
authors.initials: B
authors.lastname: Vendeville
authors.forename: Witold M
authors.initials: WM
authors.lastname: Zaleski
authors.forename: Denis E
authors.initials: DE
authors.lastname: Pagé
authors.forename: Franco
authors.initials: F
authors.lastname: D'Onofrio
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media / Q000191:economics*; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D006978:Hypertension, Renovascular / Q000209:etiology; D008297:Male; D008875:Middle Aged; D012078:Renal Artery Obstruction / Q000150:complications / Q000000981:diagnostic imaging*; D018616:Ultrasonography, Doppler, Duplex / Q000191:economics*
chemical_list: D003287:Contrast Media