What does abnormal repolarization mean?
Defects in the cardiac repolarization are known to be associated to several life-threatening diseases [1-4]. In the electrocardiogram (ECG) such defects appear as abnormalities of the ST segment and T-wave, which can be non-invasively characterized by means of indexes.
What is meant by coronary ischemia?
Coronary ischemia, myocardial ischemia, or cardiac ischemia, is a medical term for a reduced blood flow in the coronary circulation through the coronary arteries. Coronary ischemia is linked to heart disease, and heart attacks. Coronary arteries deliver oxygen-rich blood to the heart muscle.
What does ischemia mean on ECG?
Ischemia is a condition in which the blood flow (and thus oxygen) is restricted or reduced in a part of the body. Cardiac ischemia is the name for decreased blood flow and oxygen to the heart muscle.
What can cause ischemic heart disease?
Risk factors for ischemic heart disease include:
- Family history of heart disease.
- High blood cholesterol.
- High blood pressure.
- High blood triglycerides.
- Physical inactivity.
- Smoking and other tobacco use.
What causes abnormal repolarization?
Repolarization can be influenced by many factors, including electrolyte shifts, ischemia, structural heart disease (cardiomyopathy) and (recent) arrhythmias.
What does repolarization mean in the heart?
Repolarization is the return of the ions to their previous resting state, which corresponds with relaxation of the myocardial muscle.
What are signs and symptoms of ischemia?
If ischemia occurs in the heart, symptoms may include:
- Chest pain (angina)
- Shortness of breath.
- Fast heartbeat.
- Shoulder or back pain.
- Neck, jaw, or arm pain.
What does repolarization on EKG mean?
Early repolarization (ER), also recognized as “J-waves” or “J-point elevation”’ is an electrocardiographic abnormality consistent with elevation of the junction between the end of the QRS complex and the beginning of the ST segment in 2 contiguous leads[9,10].
What causes cardiac repolarization?
Repolarization (phase 3 of the action potential) occurs because of an increase in potassium permeability. At the SA node, potassium permeability can be further enhanced by vagal stimulation. This has the effect of hyperpolarizing the cell and reducing the rate of firing. Sympathetic stimulation has the opposite effect.