Rigi10™ Malleable Penile Prosthesis
Also Known As
Renovascular disease, Renal vascular disease, Atherosclerotic renal artery stenosis (ARAS), Renovascular hypertension (when causing hypertension), Ischemic nephropathy (when causing kidney damage), Renal artery occlusive disease
Definition
Renal artery stenosis (RAS) is a vascular condition characterized by narrowing of one or both renal arteries, leading to reduced blood flow to the kidneys.1 This narrowing can result from two primary etiologies: atherosclerosis, which accounts for approximately 90% of cases, or fibromuscular dysplasia (FMD), which comprises around 10% of diagnoses.2 Atherosclerotic RAS typically affects the proximal third of the renal artery including the perirenal aorta and ostium, while FMD usually involves the distal two-thirds of the renal artery.3 The reduced renal perfusion activates the renin-angiotensin-aldosterone system (RAAS), which can lead to renovascular hypertension, ischemic nephropathy, and in severe cases, chronic kidney disease.4 RAS is considered a major cause of secondary hypertension, affecting approximately 1% to 10% of the 50 million people with hypertension in the United States.5
Clinical Context
Renal artery stenosis is clinically significant in several contexts, primarily as a cause of secondary hypertension and progressive renal dysfunction.1 The clinical presentation varies depending on the severity, progression, and whether the stenosis is unilateral or bilateral.
Patient Selection Criteria:
Patients who should be evaluated for RAS include those with:
- Sudden onset or worsening of hypertension, especially after age 552
- Resistant hypertension (requiring three or more medications)3
- Recurrent episodes of flash pulmonary edema or unexplained congestive heart failure4
- Unexplained progressive renal insufficiency5
- Significant disparity in kidney sizes (>1.5 cm difference)2
- Unexplained azotemia when starting ACE inhibitors or angiotensin receptor blockers3
Diagnostic Procedures:
Diagnosis typically involves a combination of clinical suspicion and imaging studies:
- Duplex Doppler ultrasonography: A noninvasive initial screening tool with variable sensitivity (60-90%)4
- Computed tomographic angiography (CTA): Offers excellent anatomical detail but requires iodinated contrast5
- Magnetic resonance angiography (MRA): Provides good visualization without iodinated contrast but may be contraindicated in patients with severe renal impairment4
- Renal arteriography: The gold standard for diagnosis but invasive and carries risks of contrast nephropathy5
Treatment Approaches:
Management strategies include:
- Medical therapy: Antihypertensive medications (particularly ACE inhibitors and ARBs in unilateral disease), statins, antiplatelet agents, and risk factor modification2,4
- Revascularization: Percutaneous transluminal renal angioplasty with stenting for selected patients with severe, hemodynamically significant stenosis, especially those with recurrent flash pulmonary edema, progressive renal dysfunction, or resistant hypertension3,5
- Surgical revascularization: Reserved for complex cases unsuitable for endovascular approaches4
Expected Outcomes:
Outcomes vary based on patient selection and intervention timing:
- Blood pressure improvement occurs in 60-80% of properly selected patients after revascularization2
- Stabilization or improvement in renal function is seen in approximately 30-50% of patients5
- Cardiovascular event reduction and survival benefit remain controversial and depend on appropriate patient selection3,4
The Cardiovascular Outcomes in Renal Atherosclerotic Lesions (CORAL) trial demonstrated that most patients with atherosclerotic RAS can be managed with optimal medical therapy alone, with revascularization reserved for specific high-risk subgroups.3,5