Mesenteric ischemia is a condition linked to the poor circulation of the blood to mesenteric organs such as stomach, liver, colon and intestine. The poor circulation of blood can lead to blockages and reduce the functioning of these organs permanently. This condition can be either acute or chronic.
Acute mesenteric ischemia occurs suddenly. It is due to blockage of oxygen-rich blood. It can permanently damage the intestines and requires immediate medical care. Chronic mesenteric ischemia occurs gradually. It is due to narrowing of one or more arteries known as visceral arteries that supply blood to the intestines.
Mesenteric ischemia may be due to four mechanisms of poor blood flow which include formation of blood clot in different part of the body and traveling to the mesenteric artery, or clot forming in the artery, or clot forming in the mesenteric vein, or spasm of the artery or less blood flow due to low blood pressure.
Acute mesenteric ischemia is caused by blood clots, which often originate in the heart. These are common in patients with an abnormal heartbeat or any other heart disease.
Chronic mesenteric ischemia is frequently associated with atherosclerosis. It slows the amount of blood flowing through the arteries. The artery becomes blocked due to the buildup of plaque which in turn leads to narrowing and stiffness in the artery. Eventually, it leads to reduced blood flow or even completely block the arteries.
The signs and symptoms of mesenteric ischemia include:
Acute Mesenteric Ischemia
Chronic Mesenteric Ischemia
Risk factors of mesenteric ischemia include atrial fibrillation, heart failure, chronic renal failure, previous history of blood clots, and myocardial infarction.
Delay in treatment may lead to complete damage or necrosis (tissue death) of the organ. Severe stages of mesenteric ischemia may lead to shock due to leakage of fluids through colon walls thereby causing dehydration or low blood pressure.
The diagnosis of mesenteric ischemia involves an initial physical examination along with the history of smoking, high blood pressure, diabetes and heart disease. The doctor also asks details about when and how often the symptoms occur and how long they last. The diagnostic tests for mesenteric ischemia include:
Doppler ultrasound or CT angiogram scan: It is used to identify arterial occlusion. It shows problems associated with the blood vessels and the intestine.
Mesenteric Angiogram:In this test, a special dye is injected into the bloodstream to highlight the arteries of the intestine. Then x-rays of the area are taken which reveal the location of blockage in the artery.
Computed Tomography (CT) scan:It creates detailed three-dimensional images of cross-sections of the body which help in identifying problems associated with arteries.
Magnetic Resonance Imaging (MRI):High-frequency radio waves along with strong magnetic field are used to take images of the body. It is very accurate in identifying proximal vascular occlusion.
The treatment for mesenteric ischemia (chronic and acute) involves providing adequate blood flow to the intestines for their proper functioning.Acute Mesenteric Ischemia
Treatment for acute mesenteric ischemia should be given immediately, as it can damage the intestines rapidly. Narcotic medications may be given to alleviate severe pain. If a clot is found thrombolytic therapy is useful. It involves injecting clot-dissolving medication into a blood vessel. If there is an evidence of intestinal damage, surgery is required to remove damaged portions of the intestine.Chronic Mesenteric Ischemia
The first-line approach for chronic mesenteric ischemia is minimally invasive endovascular treatment. Balloon angioplasty and stenting are also preferred. A tiny device with a balloon is inserted into the narrowed artery. The doctor inflates and deflates the balloon to push plaque against the wall of the artery. Once the artery is widened, a stent is inserted to support the artery walls to keep the vessel open.
Some patients may not be suitable for angioplasty and stenting. In such cases, bypass surgery is recommended. The doctor creates a detour around the narrowed or blocked section of the affected artery.
Some medications such as antibiotics, blood thinners, vasodilator drugs are also useful in treating chronic mesenteric artery ischemia.
Few lifestyle changes can reduce the risk for narrowing of arteries. The changes include: