What is the most common cause of renovascular hypertension?

The Most Common Cause of Renovascular Hypertension

The most common cause of renovascular hypertension is renal artery atheroma (atherosclerosis), which accounts for approximately 90% of all renovascular stenotic lesions. 1

Etiology of Renovascular Hypertension

• Atherosclerotic disease (90% of cases) - typically affects the aorto-ostial segment and proximal 1 cm of the main renal artery, often as a manifestation of systemic atherosclerosis 1
• Fibromuscular dysplasia (10% of cases) - typically affects the middle and distal two-thirds of the renal artery and its branches, most commonly in young women 1, 2
• Less common causes include:
  • Renal artery aneurysms 1
  • Takayasu's arteritis 1
  • Atheroemboli and thromboemboli 1
  • William's syndrome and neurofibromatosis 1
  • Spontaneous renal artery dissection 1
  • Arteriovenous malformations or fistulas 1
  • Trauma (e.g., lithotripsy, direct injury, or surgery) 1
  • Prior abdominal radiation therapy 1
  • Retroperitoneal fibrosis 1

Demographic and Clinical Patterns

• Atherosclerotic renal artery stenosis:

  • More common in older individuals 3
  • Usually involves the origin and proximal portion of the renal arteries 1
  • Often associated with other manifestations of systemic atherosclerosis 1

• Fibromuscular dysplasia:

  • More common in young women (25-50 years old) 1, 2
  • Often involves both renal arteries 1
  • Characteristically involves the middle and distal two-thirds of the main renal artery 1
  • Has a characteristic angiographic "string of beads" appearance 1

Clinical Features Suggesting Renovascular Hypertension

• Abdominal bruit 2
• Malignant or accelerated hypertension 2
• Significant hypertension in a young adult (<35 years) 2
• New onset hypertension after age 50 2
• Sudden development or worsening of hypertension 2
• Refractory hypertension 2
• Generalized arteriosclerotic occlusive disease with hypertension 2
• Acute kidney injury following administration of ACE inhibitors or ARBs 1

Diagnostic Approach

• Duplex ultrasonography is recommended as the initial screening test (Class I recommendation) 1, 2
• For patients with normal renal function, computed tomographic angiography or magnetic resonance angiography are also highly appropriate 2
• For patients with decreased renal function, duplex Doppler ultrasound is preferred, with MR angiography without IV contrast as a second choice 2

Treatment Considerations

• Medical therapy is the cornerstone for most patients with atherosclerotic renovascular disease 4
• Revascularization (angioplasty with or without stenting) is indicated for refractory hypertension, progressive decline in renal function, or circulatory congestion 1
• Angioplasty alone is the treatment of choice for fibromuscular dysplasia, with high rates of therapeutic success 1

Clinical Pitfalls to Avoid

• Don't assume all renovascular hypertension requires intervention - most cases of atherosclerotic disease can be managed medically 4
• Be cautious with ACE inhibitors or ARBs in patients with bilateral renal artery stenosis or stenosis to a solitary kidney, as they can precipitate acute renal failure 1
• Don't overlook the possibility of atherosclerotic disease developing in patients with a history of fibromuscular dysplasia as they age 5
• Remember that the mere presence of renal artery stenosis doesn't necessarily mean it's the cause of hypertension - functional assessment is important 4, 6