To evaluate the efficacy of renal artery stent combined with standardized medical therapy as treatment for renal artery stenosis.

Inclusion Criteria:

• Age between 40 - 75
• Diameter of stenosis of renal artery or main branch of renal artery ≥60％. If diameter of stenosis is 60% - 75%, pressure difference between proximal and distal end ≥20 mm Hg (1mmHg=0.133kPa) or Captopril renography positive;
• Systolic blood pressure before taking antihypertensive ≥180mmHg and/or diastolic blood pressure ≥110 mmHg; taking three antihypertensive including one diuretics with systolic blood pressure ≥140mmHg and/or ≥90 mmHg;
• length of ipsilateral kidney is greater than 7.0cm.

Exclusion Criteria:

• Estimated glomerular filtration rate (eGFR) <30 ml/ (min﹒1.73 m 2) [eGFR (mL/min/1.73 m2) = 186.3 * serum creatinine (mg/dl) -1.154 * Age-0.203 * 0.742 (female)[11];
• unstable condition and unable to tolerate interventional therapy;
• anatomy of renal artery pathology not suitable for interventional therapy;
• allergic to dihydropyridines;
• III degree atrioventricular block
• contrast allergy ;
• any known malignant tumor;
• non-compliant, history of alcoholism or drug abuse.](streamdown:incomplete-link)