A hypertensive emergency is when a patient has dangerously high blood pressure that causes complications such as organ failure. Malignant hypertension is one type of hypertensive emergency.
There is disagreement between doctors and diagnostic guides about how to characterize malignant hypertension. Some refer to the sudden onset of symptoms as the main characteristic of malignant hypertension, while others point to a combination of eye damage and very high blood pressure.
Definitions aside, blood pressure higher than 180/120 millimeters of mercury (mm Hg) is a cause for concern. Anyone who has it should receive immediate care.
Below, we describe what a hypertensive emergency is and how it is distinct from benign hypertension, a hypertensive crisis, and hypertensive urgency. We then explore the symptoms, diagnosis, and treatment for dangerously high blood pressure.
Malignant hypertension is the most severe type of high blood pressure. It qualifies as a hypertensive emergency.
Blood pressure often exceeds 180/120 mm Hg, with the bottom number above 130 or 140 mm Hg. A hypertensive emergency affects the entire body, causing damage to multiple organs and organ systems.
Doctors once defined malignant hypertension as extreme blood pressure that damages the retinas. However, health experts now recognize that the problem can present in a range of ways, and they define it more generally, noting that it can damage multiple organs.
Normal blood pressure usually ranges from 90/60 mm Hg to 130/80 mm Hg.
Benign hypertension is a less dangerous form of high blood pressure, which doctors may also call essential hypertension. It does not stem from a specific medical condition, though lifestyle factors such as smoking, eating too much salt, and obesity may play a role.
Unlike malignant hypertension, benign hypertension is not a medical emergency. It is a chronic condition, and despite its name, it can cause harm over time. For example, benign hypertension may affect the kidneys by thinning the renal cortex. It may also cause protein to leak into urine.
However, benign hypertension does not cause significant, immediate kidney damage, changes to the eyes, or widespread organ damage, as seen in hypertensive emergencies such as malignant hypertension.
If a person with benign hypertension does not receive treatment for it, it may lead to a hypertensive emergency. However, as many as 60% of people who have experienced a hypertensive emergency may have no history of benign hypertension.