Identification of Factors Associated With Improved Survival After Renal Artery Stenting

Atherosclerotic renal artery stenosis (RAS) is associated with high mortality rates, but large randomized trials have not shown improvement in survival with renal artery stenting. These results suggest that factors other than ongoing renal hypoperfusion are important in determining survival in patients with RAS. Using logistic regression models, we performed a single-center, case-control study that included 188 patients with ≥70% RAS with an average age of 67 ± 10 years, 54% women, 20% black, and 70% smokers; 118 patients (63%) underwent renal artery stenting. A total of 89 patients (47%) died during an average follow-up of 5.1 years. Previous myocardial infarction (MI) (odds ratio 2.6 95% confidence interval [1.4 to 4.7]), left ventricular ejection fraction (LVEF) ≤35% (odds ratio 4.1 95% confidence interval [1.6 to 10.6]), and renal insufficiency were predictors of mortality in this study. The risk associated with LVEF ≤35% and previous MI were additive with mortality of 40%, 54%, and 85%, respectively, with 0, 1, or both these factors. Renal artery stenting was associated with a 43% reduction in mortality in patients with 0 or 1 mortality risk factors (defined as LVEF ≤35%, previous MI, and glomerular filtration rate ≤45 ml/min/1.73 m2) but had no effect on mortality in patients with 2 or 3 mortality risk factors. Systolic blood pressure, diastolic blood pressure, or severity of RAS did not correlate with survival. In conclusion, this retrospective analysis suggests that clinical, in addition to anatomic and physiological, factors should be considered in future studies examining effects of renal artery stenting on survival.