Cath Lab Digest

Abstract

Percutaneous intervention of renal artery stenosis improves control of hypertension and to some extent, stemming progressive renal dysfunction. Dual blood supply of a kidney through 2 separate renal arteries occurs in almost 25% of the general population. Proximity of the 2 renal ostia can render endovascular intervention challenging. We report a case of simultaneous intervention of 2 renal arteries supplying the right kidney for uncontrolled hypertension and rapidly progressive renal dysfunction. Kissing balloon angioplasty and tandem stenting with bifemoral approach resulted in successful treatment of the 2 right renal arteries with excellent technical and clinical outcome.

VASCULAR DISEASE MANAGEMENT 2012;9(3):E42–E44

Key words: bifurcation lesion, kissing balloon angioplasty, renal artery stenosis, dual supply

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Angioplasty combined with stenting has resulted in most optimal angiographic outcomes for renal artery stenosis as well as improved control of hypertension and to some extent, stemming progressive renal dysfunction.¹ Dual blood supply of a kidney through 2 separate renal arteries occurs in almost 25% of the general population.² Close proximity of ostia of the 2 renal arteries can make percutaneous intervention challenging.  We report a case of simultaneous intervention of 2 renal arteries with almost a common ostium, but not quite.

Case Report

An 87-year-old male patient with long-standing hypertension, chronic kidney disease (stage 2; Glomerular filtration rate [GFR] was 73 mL/min/1.73m²; baseline creatinine 1.2-1.4 mg/dL), and diabetes mellitus, was transferred to our hospital with recent worsening of hypertension control despite taking 4 anti-hypertensive medications, and acute on chronic renal failure with rapid progression to stage 4 (GFR 22 mL/min/1.73m²; serum creatinine 2.87), after starting valsartan 2 weeks ago. He also had a history of peripheral arterial disease (previous left femoral to anterior tibial bypass graft), and coronary artery disease (CAD) (previous percutaneous coronary intervention). He was asymptomatic with no symptoms of congestive heart failure. Hyperkalemia has been treated at the transferring hospital. On admission, blood pressure was 155/76 mm Hg, and heart rate was 78 BPM. Physical examination was unremarkable. There was no jugular venous distension, crackles on chest auscultation, or lower extremity edema. Laboratory values were unremarkable except creatinine, which was elevated to 2.87 mg/dL from a baseline value of 1.2-1.4 mg/dL.

A transthoracic echocardiogram showed left ventricular ejection fraction of 50%, with grade 1 diastolic dysfunction and mild aortic stenosis. Abdominal ultrasound revealed right kidney size was 11.3 cm, and left kidney size was 10.4 cm without hydronephrosis, but slight cortical thinning bilaterally. Based on the fact that renal dysfunction occurred after starting an angiotensin receptor blocker, a renal duplex scan was performed, which revealed a renal to aortic flow velocity ratio less than 3.5, suggestive of possible bilateral severe renal artery stenosis.

Selective renal arteriography revealed a solitary left renal artery with mild stenosis. However, the right kidney had a dual arterial supply, superior and inferior right renal arteries. Ostia of the 2 renal arteries were very close, but selective arteriography could not be performed using one catheter at a time, and each one had to be engaged separately. Both the superior (Figure 1) and inferior (Figure 2) renal arteries had an ostial 95% stenosis, with a pressure gradient of 70 mm Hg. Each artery supplied almost half the kidney, and there was no true “dominant” artery. Interestingly, the 2 ostia were too close to allow for simultaneous engagement even using 2 catheters.