What clinical syndromes are associated with renal artery stenosis?
Renovascular hypertension, progressive loss of kidney function from ischemic nephropathy, and recurrent episodes of flash pulmonary edema (meaning acute/abrupt onset pulmonary edema) are the clinical syndromes typically associated with renal artery stenosis. However, renal artery stenosis can also be completely asymptomatic. In the case of renovascular hypertension, hemodynamically significant unilateral orbilateral renal artery stenosis leads to decreased perfusion pressure in one or both kidneys. This stimulates activation of the renin-angiotensin-aldosterone system, which increases systemic pressure to restore kidney perfusion distal to the stenotic lesion(s).
The pathophysiology of ischemic nephropathy is complex and likely relates to activation of multiple pathways triggered by reduced kidney perfusion that promote kidney injury and fibrosis. Flash pulmonary edema in the context of renal artery stenosis tends to occur only with bilateral stenosis (or renal artery stenosis affecting a solitary kidney). In this situation, patients are likely predisposed to episodes of pulmonary edema from enhanced tubular sodium reabsorption and volume expansion from increased renin-angiotensin-aldosterone activity in the absence of a pressure natriuresis phenomenon that would occur within an unaffected kidney.
