Abstract P433: Impact of Renal Function on Outcomes After Percutaneous Transluminal Renal Angioplasty in Hypertensive Patients With Renal Artery Stenosis

Abstract

Objective: Atherosclerotic renal artery stenosis (ARAS) is associated with secondary hypertension. Renal dysfunction is often present in ARAS patients; however, evidence for the impact of pretreatment renal function on outcomes after percutaneous transluminal renal angioplasty (PTA) is limited. Methods: A total of 139 hypertensive patients with ARAS (mean age, 69.5±8.9 years, 112 male) who underwent renal PTA were included. Renal function was evaluated based on estimated glomerular filtration rate (eGFR) and albuminuria/proteinuria, and classified into three categories according to eGFR (≥45, 30-44, <30 ml/min/1.73m 2 ) and albuminuria/proteinuria [normal-to-mild: albumin/creatinine ratio (ACR) <3.0, protein/creatinine ratio (PCR) <15; moderate: ACR 3.0-30.0, PCR 15-50; severe: ACR >30.0, PCR >50 mg/mmol]. The primary end point of this study was first occurrence of the composite of cardiovascular and renal events including all-cause death, myocardial infarction, stroke, adverse aortic events, or end-stage renal failure requiring regular hemodialysis. Results: During a median follow up of 5.4 years, 36.0% (50 of 139) of patients developed the primary composite end point including cardiovascular and renal outcomes. In multivariate Cox regression analysis, eGFR <30 (hazard ratio [HR] 3.47, p <0.01) as well as severe albuminuria/proteinuria (HR 2.63, p <0.05) was an independent predictor of worse outcome. In the subgroup without events within one year after PTA (n=117), the outcome differed among the three renal functional categories at one year based on eGFR (log-rank χ 2 =16.28, p <0.001) as well as on albuminuria/proteinuria (log-rank χ 2 =8.30, p <0.05). At one year, 24 of 117 patients (20.1%) showed a ≥20% decrease in eGFR, and their outcome was worse than that of those with a ≥20% increase (n=23) (HR 3.50, p <0.05). Multiple logistic regression analysis indicated that pretreatment moderate-to-severe albuminuria/proteinuria was an independent predictor of a ≥20% eGFR decrease (odds ratio 2.82, p <0.05). Conclusion: Impaired renal function, and in particular, a poor response of eGFR to PTA, is associated with worse outcome. Therapeutic effectiveness of renal angioplasty seems to be limited in patients with albuminuria/proteinuria.