Malignant hypertension

• Malignant (accelerated) hypertension:

  • Severe increase in BP to 180/120 mmHg or higher
  • Often over 220/120 mmHg
  • Signs of retinal haemorrhage and/or papilloedema
  • Usually associated with new or progressive target organ damage - new onset confusion, chest pain, shortness of breath, heart failure or AKI
• Refer for same-day assessment if there are:

  • Signs of retinal haemorrhage and/or papilloedema
  • Life-threatening symptoms such as new onset confusion, chest pain, signs of heart failure, or AKI (oligo/anuria)
• If there are no symptoms or signs indicating same day referral:

  • Carry out investigations for target organ damage as soon as possible
  • If target organ damage is identified, consider starting antihypertensive drug treatment immediately, without waiting for results of ABPM
  • If no target organ damage is identified, repeat BP measurement within 7 days
• Investigations:

  • Assess for target organ damage
  • Assess cardiovascular risk - serum total cholesterol and HDL cholesterol, QRISK
  • Consider the need for investigations for possible secondary causes of hypertension - identifiable cause more likely when hypertension occurs in people under the age of 40, worsens suddenly, or presents as malignant hypertension
• Assessing for target organ damage:

  • Test for haematuria
  • Urine albumin:creatinine ratio
  • HbA1c
  • Electrolytes, creatinine and eGFR - for CKD
  • Examine the fundi - hypertensive retinopathy
  • 12-lead ECG - assess cardiac function and detect left ventricular hypertrophy
• If a hypertensive crisis presents in pregnancy, consider eclampsia, which is important as the treatment is different
• Aetiology:

  • More common in young adults
  • More common in males - especially African American
  • Most commonly the result of essential hypertension, but can also result from other secondary causes of hypertension:
  • Common in those with collagen vascular disorders e.g. SLE, systemic sclerosis
  • Patients with kidney failure or renal hypertension as a result of renal artery stenosis
  • Associated with eclampsia in pregnancy
• The effects of malignant hypertension can include:

  • Renal failure
  • Pulmonary Oedema
  • Encephalopathy
  • Cerebrovascular haemorrhage
  • Papilloedema
• Signs and symptoms:

  • Changes in GCS - anxiety, confusion, lethargy
  • Signs of increased ICP - headache, nausea and vomiting, subarachnoid/cerebral haemorrhage, seizures
  • Blurred vision
  • Chest pain -crushing/pressure
  • Cough
  • Reduced urine output
  • Shortness of breath
  • Paraesthesia/weakness
• Ophthalmoscopy:

  • Bleeding of the retina - flame haemorrhages
  • Narrowing of the retinal blood vessels - AV nipping
  • Papilloedema - must be present for the diagnosis of malignant hypertension to be made
  • Hard exudates
  • Cotton wool spots
• Acute investigations:

  • CXR - congestion/oedema, cardiomegaly
  • Head CT - signs of raised ICP
  • ECG - ischaemia, arrhythmias
  • Troponin - cardiac ischaemia
  • Pathological hallmark = fibrinoid necrosis - endothelial damage, followed by leakage of plasma proteins, including fibrinogen from the vessel lumen - diagnosed via microscopy
• Management:

  • Medical emergency
  • Blood pressure should be lowered slowly over a period of days - sudden drop in BP increase risk of stroke
  • Insertion of arterial line or measure BP at least every 5 minutes via a non-invasive method
  • IV antihypertensive with a short duration of action e.g. hydralazine or metoprolol
  • Treat end-organ effects - diuretics for pulmonary oedema, consider dialysis for renal failure
• Possible complications include:

  • Brain damage (stroke, seizures)
  • MI, angina, heart rhythm disturbances
  • Acute renal failure
  • Blindness
  • Pulmonary oedema