Hypertensive Crisis Definition
A hypertensive crisis is defined as blood pressure ≥180/120 mmHg, and is further classified into two distinct categories: hypertensive emergency (with acute target organ damage requiring immediate BP reduction) and hypertensive urgency (without acute organ damage, not requiring immediate aggressive treatment). 1, 2
Key Distinguishing Features
Hypertensive Emergency
- BP ≥180/120 mmHg PLUS evidence of acute target organ damage
- Requires immediate ICU admission and parenteral therapy 1
- Associated with 10% in-hospital mortality and 20-30% one-year cardiovascular morbidity/mortality 1
Common manifestations of acute target organ damage include:
- Acute heart failure/pulmonary edema
- Neurologic disorders (encephalopathy, intracranial hemorrhage, acute ischemic stroke)
- Acute kidney injury
- Acute aortic dissection (least common but most critical)
- Acute myocardial ischemia
- Retinopathy with flame hemorrhages, cotton wool spots, or papilledema 1, 2
Hypertensive Urgency (Previously Used Term)
- BP >180/120 mmHg WITHOUT acute target organ damage
- Does NOT require aggressive short-term BP lowering 1
- Should NOT receive parenteral antihypertensive therapy 1
- Managed with oral medications in outpatient setting 1, 2
Special Consideration: Malignant Hypertension
The 2024 ESC guidelines 2 define malignant hypertension as a specific subset characterized by:
- Extreme BP elevations with acute microvascular damage (microangiopathy)
- Small-artery fibrinoid necrosis in kidneys, retina, and brain
- Hallmark finding: retinopathy with papilledema
- May include disseminated intravascular coagulation
Critical Clinical Pitfall
The most important pitfall is treating severe hypertension without organ damage as an emergency. Patients hospitalized for noncardiac conditions with BP >180/120 mmHg but no acute target organ damage should NOT receive intermittent IV or aggressive oral antihypertensives to acutely reduce BP 1. This approach causes harm without benefit.
Additionally, many patients in emergency settings have transiently elevated BP due to pain or distress that normalizes when the underlying issue is addressed, rather than requiring specific antihypertensive intervention 2.
Symptom Recognition
Symptoms depend on affected organs but may include:
- Headache, visual disturbances
- Chest pain, shortness of breath
- Dizziness, neurological deficits
- In hypertensive encephalopathy: somnolence, lethargy, seizures, cortical blindness preceding loss of consciousness 2
Important caveat: Focal neurological lesions are rare in hypertensive encephalopathy and should raise suspicion for stroke instead 2.