In general terms, ischemia is the reduction or interruption of blood flow to a part of the body. This results in a decreased supply of both oxygen and essential nutrients to the affected tissues.
When oxygen and nutrients are lacking, cellular damage can occur, and if left untreated, it can lead to tissue death, known as necrosis.
The causes of ischemia can be diverse, including atherosclerosis (narrowing of blood vessels), the presence of blood clots, or compression of the vessels due to swelling or tumors.
The severity of the situation depends on the duration of the blood flow interruption and the type of organ or tissue affected.
Some forms of ischemia may be temporary and reversible, while others can cause permanent damage.
Types of Ischemia
When explaining what ischemia is and the types that exist, they are generally classified based on the duration or the area affected by the blood flow interruption:
- Acute ischemia: Occurs suddenly and is usually due to an abrupt event like a blood clot or an embolism. This condition can be hazardous and requires immediate medical attention.
- Chronic ischemia: Develops gradually and is often the result of long-term conditions such as blood vessel narrowing. While it may not show symptoms in its early stages, over time, it can lead to serious complications like skin ulcers, gangrene, or heart failure.
- Silent ischemia: A type of ischemia that does not produce obvious symptoms. It is particularly dangerous because it can go unnoticed and untreated. It often occurs in patients with diabetes or heart disease.
- Focal ischemia: Affects a specific region of the body, such as in the case of a stroke.
- Global ischemia: Affects an entire organ or system and occurs when blood flow is drastically reduced for a prolonged period. It is often the result of cardiac arrest or a severe drop in blood pressure.
Among the various types of ischemia—such as subepicardial ischemia, intestinal ischemia, lower limb ischemia, ischemic heart disease, and cerebral ischemia — are ischemic heart disease and cerebral ischemia are among the most common.
Ischemic Heart Disease
Ischemic heart disease, also known as coronary artery disease, is a condition in which blood flow to the myocardium (the heart muscle) is reduced or blocked, typically due to the buildup of fatty plaques in the coronary arteries. These arteries are responsible for supplying both nutrients and oxygen to the heart.
In cardiac ischemia, blood flow is reduced, and the heart cannot receive enough oxygen. This may cause angina (chest pain) or, in more severe cases, myocardial infarction (heart attack).
There may also be subepicardial ischemia, which affects the outer part of the heart.
Ischemic heart disease is one of the leading causes of death worldwide.
Cerebral Ischemia
Cerebral ischemia is a condition in which blood flow to the brain is interrupted or reduced. This limits the supply of oxygen and essential nutrients needed for proper brain function.
Cerebral ischemia can lead to an ischemic stroke, one of the main causes of disability and mortality. Depending on the affected area, it can be focal cerebral ischemia, affecting a specific region of the brain, or global cerebral ischemia, which impacts the entire brain.
Regardless of the affected area, reduced blood flow can cause severe damage to the tissue, organ, and, of course, the overall health of the person.
At the ABC Medical Center’s Vascular, Arterial, and Venous Disease Department, we can provide you with specialized care. Contact us!
Fuentes:
Texas Heart Institute, Scielo, Elsevier
