The electrocardiogram (ECG) is an essential diagnostic test for patients with possible or established myocardial ischemia, injury, or infarction.
Exercise ECG is widely used for the diagnosis of ischemic heart disease. The most common ECG sign of myocardial ischemia is flat or down-sloping ST-segment depression of 1.0 mm or greater.
Myocardial ischemia (or cardiac ischemia) means your heart muscle is not getting enough blood (which contains oxygen and nutrients) to work as it should. If this lack of blood from your coronary arteries is severe or goes on for more than a few minutes, it can damage your heart muscle.
The current ECG standards for diagnosing acute ischemia/infarction require that ST-segment elevation be present in 2 or more contiguous leads and that the elevation of the ST segment at the J point be greater than 0.2 mV (2 mm with standard calibration) in leads V1, V2, and V3 and greater than 0.1 mV in all other leads ...
An ECG stress test is considered positive for ischemia if there is at least a 1-mm horizontal or down-sloping ST-segment depression. Up-sloping ST-segment depression is not considered a positive finding. An ST-segment elevation greater than 1 mm is highly suggestive of significant ischemia.
Many people have ischemic episodes without knowing it or having pain — silent ischemia. They may have a heart attack with no warning. People with angina also may have undiagnosed episodes of silent ischemia.
Important increases in heart rate occur before the onset of ischemia during daily life, but this increase occurs much earlier than has been reported.
An ECG is pretty accurate at diagnosing many types of heart disease, although it doesn't always pick up every heart problem. You may have a perfectly normal ECG, yet still have a heart condition.
Of the body organs, the brain exhibits the highest sensitivity to ischemia.
When they do occur, the most common is chest pressure or pain, typically on the left side of the body (angina pectoris). Other signs and symptoms — which might be experienced more commonly by women, older people and people with diabetes — include: Neck or jaw pain. Shoulder or arm pain.
ST depression due to subendocardial ischaemia is usually widespread — typically present in leads I, II, V4-6 and a variable number of additional leads. A pattern of widespread ST depression plus ST elevation in aVR > 1 mm is suggestive of left main coronary artery occlusion.
Silent myocardial ischemia is a condition of reduced oxygen-rich blood flow to the heart that occurs in the absence of chest discomfort or other symptoms of angina, e.g., dyspnea, nausea, diaphoresis, etc.
Although there are no specific blood tests to indicate intestinal ischemia, certain general blood test results might suggest intestinal ischemia. An example of such a result is an increase in white cell count. Imaging tests.
A zone of ischemia typically produces ST segment depression. A zone of injury produces ST segment elevation. A zone of infarction produces a large Q wave in the QRS complex.
Valvular defects cannot be detected using an ECG. Chest X-ray can be used to determine such defects. Therefore, an ECG can detect arrhythmia, myocardial infarction and also heart block but not valvular defects.
Ulcers in stomach or Gastric ulcers cannot be detected by an ECG.
Ischemic cardiomyopathy symptoms may include: Shortness of breath. Swelling in your legs and feet (edema). Fatigue that makes you unable to exercise or carry out everyday activities.
Chronic mesenteric ischemia.
It is also known as hardening of the arteries. As plaque builds, it starts to block blood flow through your artery. This type of ischemia may come and go for a while, and then become constant.
Although both mental stress and conventional stress can provoke ischemia by increasing myocardial oxygen demand, nonsystemic hemodynamic factors may contribute to mental stress–induced ischemia.
Six Ps — The six Ps of acute ischemia include pain, pallor, poikilothermia, pulselessness, paresthesia, and paralysis.
The signs of early ischemia on CT are (1) decreased parenchymal x-ray attenuation, (2) tissue swelling (mass effect), and (3) hyperattenuated artery sign (arterial occlusion).
Overview. A transient ischemic attack (TIA) is a temporary period of symptoms similar to those of a stroke. A TIA usually lasts only a few minutes and doesn't cause permanent damage.