What Is Myocardial Ischemia?

Myocardial ischemia is a serious heart condition triggered by an artery obstruction. Frequently associated with medical conditions that compromise arterial function, such as atherosclerosis, myocardial ischemia can sometimes come on suddenly. Treatment for myocardial ischemia is usually determined by the severity of one's condition and often involves the use of medication to ease symptoms. When medication is insufficient, surgery may be performed to alleviate the artery obstruction and restore blood flow.

Ischemia is a term used to describe diminished arterial blood flow. Reduced circulation through the heart, known as myocardial or cardiac ischemia, occurs when the arteries that supply the heart become constricted or blocked. When blood flow is jeopardized, the amount of oxygenated blood reaching the heart muscle is likewise diminished, forcing the heart to work harder than it would normally.

A diagnosis of myocardial ischemia may be confirmed with diagnostic and laboratory testing. Angiography, electro- and echocardiograms, and blood tests are often performed to evaluate cardiovascular health and check for markers indicative of heart damage. If atherosclerosis is suspected, the individual may undergo a computerized tomography (CT) scan to evaluate the severity of the arterial constriction and diminished cardiovascular blood flow.

Generally diagnosed as a progressive condition, myocardial ischemia may start from an existing cardiovascular dysfunction. Acute cardiac ischemia can result from sudden arterial obstruction caused by a blood clot or piece of dislodged plaque. Severe, systemic infection and hypotension, or low blood pressure, may also cause a reduction in arterial blood flow causing ischemic symptoms.

Smoking, obesity and a sedentary lifestyle dramatically increase one’s risk for cardiac ischemia. Individuals with chronic conditions that compromise cardiovascular blood flow, such as high blood pressure, also have an increased chance for ischemic symptoms. Those with a family history of heart disease should take precautions to reduce their risk for myocardial ischemia.

It is entirely possible for someone with cardiac ischemia to remain asymptomatic, meaning he or she does not experience any signs that something is wrong. Those who are symptomatic may only demonstrate subtle signs, like episodic nausea and clamminess. As ischemia worsens, angina and shortness of breath with little to no exertion can develop. Acute myocardial ischemia has the same signs, but they are more pronounced. If ischemic signs are ignored, the heart may become arrhythmic or sustain irreversible damage.

Myocardial ischemia that is related to an existing condition may necessitate medication over the long term to reduce one’s risk for symptom progression and complications. Aspirin, angiotensin-converting enzyme (ACE) inhibitors, and beta blockers are frequently used to reduce one's risk for blood clots, ease arterial constriction, and lessen stress on the heart. If drug therapy proves inadequate, surgery may be necessary to unblock or bypass the affected artery to restore proper blood flow.