title: Relationship between hemodynamic parameters of renal artery stenosis and the changes of kidney function after renal artery stenting in patients with hypertension and preserved renal function.
abstract: BACKGROUND
  The role of physiological assessment of renal artery stenosis (RAS) using renal fractional flow reserve (rFFR) and resting translesional pressures ratio (Pd/Pa ratio) in the prediction of benefit from revascularization is still unknown.
  
  
  OBJECTIVE
  The aim of the study was to assess the relationship between hemodynamic data and the change in kidney function after renal artery stenting in secondary hypertension.
  
  
  METHODS
  34 hypertensive patients (50% males, median age 65 years) with at least 60% RAS, underwent stenting and were followed up for 6 months. Pd/Pa ratio (ratio of mean distal to lesion to proximal pressure) and hyperemic rFFR (after papaverine) were measured before the procedure. At baseline and after 6 months, the glomerular filtration rate (eGFR), serum cystatin C and albuminuria were determined. In receiver operating characteristic curves, two previously established cut-off values with the highest accuracy of identifying severe RAS were used: 0.93 for the Pd/Pa ratio and 0.8 for the rFFR.
  
  
  RESULTS
  No significant difference in eGFR was found between patients with decreased and normal Pd/Pa ratio (1.4 vs 7.9 ml/min, p = ns). Similarly, minor changes in eGFR were observed in patients with decreased vs normal rFFR (2.4 vs 4.1 ml/min, p = ns). In patients with decreased Pd/Pa ratio, albuminuria remained stable (change 1.4 mg/24 h) compared with an increase of 12.6 mg/24 h in the subgroup with Pd/Pa ≥ 0.93(p < 0.05). However, after exclusion of two outliers with significant baseline proteinuria (425 and 1095 mg/24 h, respectively), the difference in albuminuria change according to the baseline Pd/Pa ratio was no longer maintained.
  
  
  CONCLUSIONS
  Hemodynamic parameters of RAS do not distinguish the patients who may benefit from renal artery stenting in terms of kidney function improvement in short-term follow-up.
authors.affiliation: Institute of Cardiology , Warsaw , Poland.
authors.forename: Jacek
authors.initials: J
authors.lastname: Kądziela
authors.forename: Aleksander
authors.initials: A
authors.lastname: Prejbisz
authors.forename: Ilona
authors.initials: I
authors.lastname: Michałowska
authors.forename: Marcin
authors.initials: M
authors.lastname: Adamczak
authors.forename: Ewa
authors.initials: E
authors.lastname: Warchoł-Celińska
authors.forename: Barbara
authors.initials: B
authors.lastname: Pregowska-Chwała
authors.forename: Magdalena
authors.initials: M
authors.lastname: Januszewicz
authors.forename: Andrzej
authors.initials: A
authors.lastname: Więcek
authors.forename: Andrzej
authors.initials: A
authors.lastname: Januszewicz
authors.forename: Adam
authors.initials: A
authors.lastname: Witkowski
mesh_terms: D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006439:Hemodynamics; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000503:physiopathology / Q000601:surgery; D007668:Kidney / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012078:Renal Artery Obstruction / Q000150:complications / Q000503:physiopathology / Q000601:surgery; D015607:Stents
keywords: Arterial hypertension; Pd/Pa ratio; fractional flow reserve; renal artery stenosis; renal artery stenting