TOC | Cardiology   

Renovascular Hypertension  - unilateral or bilateral stenosis 

REF:  Cleveland Clinic J of Med  Dec. 2005, Vol. 72: 1135 

Causes of Renovascular Hypertension:

  1. Atherosclerosis of renal arteries (accounts for nearly 90% of cases)

  2. Fibromuscular dysplasia of renal artery (accounts for nearly 10% of cases)
     - intimal 1-2%, periarteirla 1-2%, medial 96%

  3. Renal artery aneurysm

  4. Systemic vasculitis

  5. Arteriovenous fistula

  6. Subcapsular intrarenal hematoma (Page kidney)

  7. Renin-secreting renal tumors

  8. Extrinsic compression of either kidney or renal artery due to tumors or metastases

  9. Aortic coarctation 

Clinical Features of Renovascular Hypertension:

Suggestive features: 

Tests for evaluating the renal arteries: 

  1. Plasma renin activity
    Limitations: - affected by BP meds & diet and relatively low sensitivity 57% and specificity 66%.

  2. Renal vein renin ratio 
    Limitations: - invasive, lacks sensitivity & specificity, influenced by drugs and volume status.

  3. Captopril renography 
    Limitations: lack of accuray with serum creat >2 mg/dL and bilateral disease; patients should be off diuretics and ACE inhibitors 1-2 weeks before testing.

  4. Duplex renal artery sonography - popular screening test 
    Advantages: useful in serial measuements; additional info regarding kidney size or hydronephrosis.
    Limitations: - highly operator-dependent; limited by obesity, bowel gas interference

  5. Magnetic resonance angiography (MRA) - * 
    Advantages: low nephrotoxic potential
    Limitations: - high cost; signal corruption due to metallic stents 

  6. CT angiography 
    Advantages:  improved visiualization of branch vessels 
    Limitations: - limited use in renal insufficiency due to high contrast requirement of >150 mL 

  7. Renal arteriography with contrast remaisn the gold standard to determine the degree & location of renal aratery stenosis.
    Limitations: can cause deterioration of renal function due to contrast nephropathy, atheroembolic disease, or both. 

Indications for Revascularization if stenosis is present:

Invasive treatment for Renovascular Hypertension: 

Medical Therapy for Renovascular Hypertension
- ACE inhibitors (as Lisinopril type med) or ARB (as Cozaar) are widely accepted as being superior to other antihypertensive drugs in controlling renovascular hypertension, but it has the potential to precipitate acute renal failure.  Close follow-up of kidney function and potassium levels should be done.
- Treatment for hyperlipidemia and diabetes if present, off smoking, exercise, etc. 


HYPERTENSION- Secondary                     See also BP Medications  |  Hypertensive Crisis

Secondary hypertension is hypertension of known etiology. It accounts for fewer than 5% of all cases of hypertension.

Clinical clues for secondary hypertension:

Causes of Secondary Hypertension:





Aortic Coarctation  
(weak or absent femoral pulses ) - A constriction (discrete or of varying lengths) of the aorta usually located just distal to the left subclavian artery at the junction of the ligamentum arteriosum.

[Ref: Dambro: Griffith's 5-Minute Clinical Consult, 1999]


Endocrine Causes:


Renal Causes:

Pregnancy-induced Hypertension

Neurological disorders:

Acute Stress, including surgery

Alcohol & drug use

Increased intravascular volume

Systolic Hypertension


The JNC 7 report. JAMA 2003 May 21; 289:2560-72. [Abstract]
Heart Disease 5th Ed, 1997 - Braunwald
Scientific American Medicine 1999
Postgrad Med Symposium on Hypertension  May 1, 1999;105

The 6th Report of the Joint National Committee 1997  | Quick Note
WHO 1999 Hypertension Treatment Guideline  
Medscape Hypertension Management