A Curious Case of Hypertensive Emergency and Acute Kidney Injury

A 75-year-old female with history of a prior right renal artery stent (coronary bare metal stent, duration 3 years), stage IV CKD (baseline serum creatinine (Scr) 2.1-2.3 mg/dL (eGFR 20-23 ml/min/1.73 m2 )), diastolic heart failure, and hypertension. She had multiple hospital admissions for acute decompensated heart failure, now presenting with worsening dyspnea, increased oxygen requirements of 4 L oxygen via nasal canula, increased from baseline 2 L. Despite treatment with up to nine anti-hypertensive medications, her systolic BP remained 180-200 mmHg. Her Scr also increased to 3.92. Work-up showed normal kidney sizes and urine protein/creatinine ratio 1.26 g/g. Renal artery duplex revealed right renal artery peak systolic velocity 267 cm/sec, renal-to-aortic ratio 2.68, and resistive index 0.7-0.9, suggestive of right renal artery re-stenosis and some intrinsic damage. Due to progressive volume overload and worsening respiratory status, she required temporary hemodialysis. As her volume status improved, she underwent CO2 angiogram and was found to have 90% diffuse in-stent restenosis with marked deformity of the previous stent. She underwent re-stenting of the right renal artery with a proprietary FDA-approved Herculink Elite® renal stent with only 8 ml of contrast. Immediately post-intervention, her BP dramatically improved and after two months, hemodialysis was stopped, (new baseline SCr 1.5-1.9) and she only required two BP medications.