Predictors of clinical outcome after stent placement in atherosclerotic renal artery stenosis: a systematic review and meta-analysis of prospective studies.

Objective To determine clinical predictors for blood pressure and/or renal function improvement after renal artery stent placement in atherosclerotic renal artery stenosis (ARAS). Methods We searched PubMed, EMBASE and Cochrane databases for prospective studies investigating clinical predictive variables for renal function and/or blood pressure improvement after stent placement in ARAS. Eleven studies (1552 participants) were selected for our systematic review and meta-analysis. Meta-regression analysis was performed to investigate heterogeneity and to determine independent predictors for the outcome variables. Bias was evaluated by use of the Cochrane risk of bias tool. Results Multivariate meta-regression analysis showed no predictors for renal function improvement. High baseline diastolic blood pressure (DBP) and pulse pressure were significantly associated with the decrease in blood pressure after intervention. These results were consistent with the predictors reported by the individual studies. Meta-analysis showed a nonsignificant decline in serum creatinine of 4.7 mu mol/l [95% confidence interval (CI) -13.8 to 4.5]. Overall, systolic blood pressure (SBP) fell by 19.2mmHg (95% CI -22.7 to -15.7) and DBP decreased 8.9mmHg (95% CI -10.8 to -7.0). Risk of bias was present in the majority of the studies. Conclusions The present review did not find a clinical characteristic that reliably predicts renal function outcome. High baseline pulse pressure predicted a smaller decrease in SBP after intervention and the best clinical predictor for a larger DBP reduction was a high pretreatment DBP. J Hypertens 28:2370-2377 (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.