Renal Artery Stenosis (Unilateral)

Renal artery stenosis (unilateral) is a condition where one of the arteries supplying blood to a kidney becomes narrowed. This narrowing affects the renal system, which is responsible for filtering blood and producing urine. When the artery is narrowed, the affected kidney receives less blood, which can cause it to release hormones that raise blood pressure. This often leads to high blood pressure that is difficult to control. The condition can also reduce kidney function on the affected side, potentially causing damage over time. Symptoms may be subtle or absent initially, but the main health impact is related to hypertension and possible kidney impairment.

Renal artery stenosis (unilateral) is defined as a significant narrowing of one renal artery, most commonly caused by atherosclerosis in older adults or fibromuscular dysplasia in younger patients. This stenosis leads to reduced renal perfusion pressure, triggering activation of the renin-angiotensin-aldosterone system (RAAS), which causes systemic hypertension. The unilateral nature means only one kidney is affected, often resulting in compensatory changes in the contralateral kidney. Clinically, it is a major cause of secondary hypertension and can lead to ischemic nephropathy if untreated. Diagnosis is important because it may be reversible with appropriate intervention. The condition is characterized by renal hypoperfusion, elevated plasma renin activity, and often resistant hypertension.