Ischemia
Ischemia refers to the interruption or temporary restriction of blood flow to a specific area of the body, which can lead to serious health issues if not addressed. Common causes include blood clots and atherosclerosis, a condition where arteries become narrowed due to fat deposits. Symptoms of ischemia vary based on the affected area; for example, when it impacts the brain, individuals may experience confusion, impaired speech, double vision, or facial numbness. Ischemia can result in transient ischemic attacks (TIAs), which are temporary episodes, or more severe conditions such as ischemic strokes and myocardial infarctions (heart attacks) if blood flow is restricted for longer durations.
Diagnosis often involves imaging techniques like echocardiography or magnetic resonance angiography (MRA) to assess blood flow and detect any damage. Treatment options include drug therapies, such as aspirin and nitroglycerin, and surgical procedures like angioplasty to restore blood flow. Understanding the importance of a balanced diet and regular exercise, alongside managing hypertension and atherosclerosis, is vital for reducing the risk of ischemic attacks. Overall, ischemia is a significant medical concern that warrants prompt attention to prevent potential long-term damage.
Ischemia
ANATOMY OR SYSTEM AFFECTED: Blood vessels, brain, circulatory system
DEFINITION: The interruption or temporary restriction of blood flow to a particular area of the body, such as an organ.
CAUSES: Blood clots, atherosclerosis
SYMPTOMS: Depends on location; may include confusion, impaired speech, double vision, numbness on one side of face, chest pain
DURATION: May be temporary or permanent
TREATMENTS: Drug therapy (e.g., aspirin, nitroglycerin), surgery (e.g., angioplasty)
Causes and Symptoms
When a localized area of the does not receive enough blood, neurons and supportive tissue such as glia are deprived of the essential oxygen and glucose that keep them alive. If the brain does not receive sufficient blood for even a few minutes, the result is an ischemic stroke.
Although it is possible for ischemia to have no detectable symptoms, when it occurs to the internal carotid, middle cerebral, or vertebral-basilar arteries, symptoms such as confusion, impaired speech, double vision, or on one side of the face can be experienced. In some instances, these symptoms are temporary and do not result in permanent damage (these are called transient ischemic attacks, or TIAs), but if the interruption of blood flow lasts long enough, permanent damage (a stroke) occurs. If blood flow is restricted to the coronary artery of the heart (cardiac ischemia), then the heart muscle may suffer permanent damage (myocardial infarction). Symptoms of cardiac ischemia may include chest pain.
Ischemia is commonly caused by the formation of blood clots or by atherosclerosis, in which the walls of the become narrowed as a result of the buildup of fat deposits.
Treatment and Therapy
The risk of ischemia can be assessed with high-resolution ultrasound equipment or magnetic resonance (MRA) to detect blood flow. It is common to use or to visualize damaged brain tissue and determine if the damage is ischemia caused by a blocked blood vessel or by a burst blood vessel (cerebral hemorrhage). Cardiac ischemia can be diagnosed by electrocardiography, echocardiography, or angiography. Drug therapies such as administering aspirin or stronger blood-thinning agents help when ischemia is caused by clotting. Nitroglycerin can quickly open up and reduce the chest pain experienced when the heart is affected. Drugs that lower are also helpful treatments.
Surgery might be needed to correct an that cannot be dissolved. Angioplasty can be used to expand affected arteries, particularly when the cause is atherosclerosis.
Perspective and Prospects
Rudolf Virchow, a nineteenth century German physician, was the first to use the term ischemia. Since the time that ischemia was originally identified, diagnostics have been improved through the use of echocardiograms that send out sound waves to create an image of the heart’s internal structures and through angiograms that can pinpoint the area of arterial narrowing. Treatment improvements for damage to the brain include the administration of unique drugs that can mitigate damage to surrounding nerve cells indirectly affected by the lack of blood.
Much has been learned about the need for a balanced diet, for regular exercise, for controlling hypertension, and for preventing or treating atherosclerosis as means to reduce the likelihood of suffering from an ischemic attack.
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