High Blood Pressure and Hemorrhagic Stroke

Bleeding inside the brain
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High blood pressure may cause strokes due to bleeding in the brain. Most strokes occur due to a blockage of blood flow to a part of the brain, but approximately 15% of strokes occur due to bleeding in the brain. These are known as hemorrhagic strokes. Of all the causes of hemorrhagic stroke, high blood pressure is the most common, accounting for approximately 80% of all cases.

High Blood Pressure as a Risk Factor for Stroke

No matter what stroke risk factors a person might carry with him, suffering from high blood pressure  can significantly increase his risk of suffering a hemorrhagic stroke.

This risk is even more pronounced in the elderly, in people who smoke, in men, in diabetics, and in people who drink alcohol.

High blood pressure causes intracerebral hemorrhage (ICH) by damaging the fragile walls of small arteries inside the deeper areas the brain. These are the same arteries affected by lacunar strokes, which are so common in white matter areas. The areas most commonly damaged by ICH are the brainstem, the internal capsule and the cerebellum.

In some cases the bleeding caused by high blood pressure is so large that blood spills into the brain's ventricles causing an intraventricular hemorrhage, a condition which can result in life-threatening hydrocephalus.

What Are the Symptoms?

The symptoms of ICH caused by high blood pressure vary depending on the location and size of the bleeding. Symptoms can therefore consist of:

  • Weakness of the face and/or arm, and/or leg on one side of the body
  • Numbness in the face, and/or arm, and/or leg one side of the body
  • Inability to understand spoken language or inability to speak
  • Inability or difficulty writing or reading
  • Vertigo and/or gait imbalance with or without nausea or vomiting
  • Severe headache or double vision

In rare cases, the bleeding caused by high blood pressure is so profuse that it leads to a rapid increase in intracranial pressure, which causes patients to become unresponsive, paralyzed or comatose.

But by symptoms alone it is not possible to distinguish whether a given stroke is the result of poor blood flow, or profuse bleeding. This is an important reason why special tests are required to diagnose bleeding in the brain (see below).

How Is it Diagnosed?

When a person comes to the emergency room with stroke symptoms, physicians routinely perform imaging tests to look for bleeding in the brain. The first test performed usually is a head CT, which is a rapid and reliable way to rule out this possibility. When bleeding is found but the source of the bleeding is not clear, other tests such as a cerebral angiogram or an MRI of the brain with contrast can be performed. These tests help to diagnose other causes of bleeding such as AVM, aneurysms, amyloid angiopathy, or brain tumors.

What Is the Treatment?

The treatment of bleeding in the brain from high blood pressure starts by bringing the patient to the intensive care unit for proper stabilization and diagnosis. This is done by physicians who specialize in critical care medicine.

Usually, blood pressure is controlled in order to prevent further bleeding. Other possible interventions are decided based on the size of the bleeding, on the severity of the symptoms exhibited by the patient, and on whether the interventions being considered can be expected to make a difference in the overall outcome. In some cases, bleeding must be evacuated immediately, because it threatens to harm the brain. In other cases, the risks of surgery clearly outweigh the potential benefits, leading doctors and families to refrain from further treatment. And in the grimmest of cases, bleeding has caused so much damage to the brain that surgical intervention is futile.

For some people, proper treatment might require the use of mechanical ventilation, the implantation of an ICP monitor, and/or the temporary or permanent placement of a feeding tube.


Source: J. P. Mohr, Dennis W. Choi, James C. Grotta, Bryce Weir, Phillip A. Wolf Stroke: Pathophysiology, Diagnosis, and Management Churchill Livingstone; 4th edition (2004)

Sessa M; Intracerebral hemorrhage and hypertension; Neurol Sci. 2008 Sep;29 Suppl 2:S258-9

Edited by Heidi Moawad MD

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