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Strain Pattern
In electrocardiography, a strain pattern is a well-recognized marker for the presence of anatomic left ventricular hypertrophy (LVH) in the form of ST depression and T wave inversion on a resting ECG.Okin, PM Devereux, RB, Nieminen, MS et al (2001)“Relationship of the electrocardiographic strain pattern to left ventricular structure and function in hypertensive patients: the LIFE study” ''Journal of the American College of Cardiology'';38(2):514-520. doi:10.1016/S0735-1097(01)01378-X It is an abnormality of repolarization and it has been associated with an adverse prognosis in a variety heart disease patients. It has been important in refining the role of ECG LVH criteria in cardiac risk stratification. It is thought that a strain pattern could also reflect underlying coronary heart disease Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves the reduction of blood flow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrocardiography
Electrocardiography is the process of producing an electrocardiogram (ECG or EKG), a recording of the heart's electrical activity. It is an electrogram of the heart which is a graph of voltage versus time of the electrical activity of the heart using electrodes placed on the skin. These electrodes detect the small electrical changes that are a consequence of cardiac muscle depolarization followed by repolarization during each cardiac cycle (heartbeat). Changes in the normal ECG pattern occur in numerous cardiac abnormalities, including cardiac rhythm disturbances (such as atrial fibrillation and ventricular tachycardia), inadequate coronary artery blood flow (such as myocardial ischemia and myocardial infarction), and electrolyte disturbances (such as hypokalemia and hyperkalemia). Traditionally, "ECG" usually means a 12-lead ECG taken while lying down as discussed below. However, other devices can record the electrical activity of the heart such as a Holter monitor but also s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Left Ventricular Hypertrophy
Left ventricular hypertrophy (LVH) is thickening of the heart muscle of the left ventricle of the heart, that is, left-sided ventricular hypertrophy and resulting increased left ventricular mass. Causes While ventricular hypertrophy occurs naturally as a reaction to aerobic exercise and strength training, it is most frequently referred to as a pathological reaction to cardiovascular disease, or high blood pressure. It is one aspect of ventricular remodeling. While LVH itself is not a disease, it is usually a marker for disease involving the heart. Disease processes that can cause LVH include any disease that increases the afterload that the heart has to contract against, and some primary diseases of the muscle of the heart. Causes of increased afterload that can cause LVH include aortic stenosis, aortic insufficiency and hypertension. Primary disease of the muscle of the heart that cause LVH are known as hypertrophic cardiomyopathies, which can lead into heart failure. Lon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ST Depression
ST depression refers to a finding on an electrocardiogram, wherein the trace in the ST segment is abnormally low below the baseline. Causes It is often a sign of myocardial ischemia, of which coronary insufficiency is a major cause. Other ischemic heart diseases causing ST depression include: * Subendocardial ischemia or even infarction. Subendocardial means non full thickness ischemia. In contrast, ST elevation is transmural (or full thickness) ischemia * Non Q-wave myocardial infarction * Reciprocal changes in acute Q-wave myocardial infarction (e.g., ST depression in leads I & aVL with acute inferior myocardial infarction) * ST segment depression and T-wave changes may be seen in patients with unstable angina Depressed but ''upsloping'' ST segment generally rules out ischemia as a cause. Also, it can be a normal variant or artifacts, such as: * Pseudo-ST-depression, which is a wandering baseline due to poor skin contact of the electrode MicroEKG ManualRetrieved September 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T Wave
In electrocardiography, the T wave represents the repolarization of the ventricles. The interval from the beginning of the QRS complex to the apex of the T wave is referred to as the ''absolute refractory period''. The last half of the T wave is referred to as the ''relative refractory period'' or ''vulnerable period''. The T wave contains more information than the QT interval. The T wave can be described by its symmetry, skewness, slope of ascending and descending limbs, amplitude and subintervals like the Tpeak–Tend interval. In most leads, the T wave is positive. This is due to the repolarization of the membrane. During ventricle contraction (QRS complex), the heart depolarizes. Repolarization of the ventricle happens in the opposite direction of depolarization and is negative current, signifying the relaxation of the cardiac muscle of the ventricles. But this negative flow causes a positive T wave; although the cell becomes more negatively charged, the net effect is in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of The American College Of Cardiology
The ''Journal of the American College of Cardiology'' is a peer-reviewed medical journal covering all aspects of cardiovascular disease, including original clinical studies, translational investigations with clear clinical relevance, state-of-the-art papers, review articles, and editorials interpreting and commenting on the research presented, published by the American College of Cardiology. Abstracting and indexing The journal is abstracted and indexed in Current Contents, EMBASE, MEDLINE, Science Citation Index, and Scopus. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor of 24.094, ranking it 4th out of 141 journals in the category "Cardiac & Cardiovascular Systems". Associated journals * ''JACC: Basic to Translational Science'' * ''JACC: CardioOncology'' * '' JACC: Cardiovascular Imaging'' * '' JACC: Cardiovascular Interventions'' * ''JACC: Case Reports'' * ''JACC: Clinical Electrophysiology'' * ''JACC: Heart Failure'' See also * ''America ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Repolarization
In neuroscience, repolarization refers to the change in membrane potential that returns it to a negative value just after the depolarization phase of an action potential which has changed the membrane potential to a positive value. The repolarization phase usually returns the membrane potential back to the resting membrane potential. The efflux of potassium (K+) ions results in the falling phase of an action potential. The ions pass through the selectivity filter of the K+ channel pore. Repolarization typically results from the movement of positively charged K+ ions out of the cell. The repolarization phase of an action potential initially results in hyperpolarization, attainment of a membrane potential, termed the afterhyperpolarization, that is more negative than the resting potential. Repolarization usually takes several milliseconds. Repolarization is a stage of an action potential in which the cell experiences a decrease of voltage due to the efflux of potassium (K+) ions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Risk Stratification
Broadly speaking, a risk assessment is the combined effort of: # identifying and analyzing potential (future) events that may negatively impact individuals, assets, and/or the environment (i.e. hazard analysis); and # making judgments "on the tolerability of the risk on the basis of a risk analysis" while considering influencing factors (i.e. risk evaluation). Put in simpler terms, a risk assessment determines possible mishaps, their likelihood and consequences, and the tolerances for such events. The results of this process may be expressed in a quantitative or qualitative fashion. Risk assessment is an inherent part of a broader risk management strategy to help reduce any potential risk-related consequences. Need Individual risk assessment Risk assessment are done in individual cases, including patient and physician interactions. Individual judgements or assessments of risk may be affected by psychological, ideological, religious or otherwise subjective factors, which impa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronary Heart Disease
Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves the reduction of blood flow to the heart muscle due to build-up of atherosclerotic plaque in the arteries of the heart. It is the most common of the cardiovascular diseases. Types include stable angina, unstable angina, myocardial infarction, and sudden cardiac death. A common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck, or jaw. Occasionally it may feel like heartburn. Usually symptoms occur with exercise or emotional stress, last less than a few minutes, and improve with rest. Shortness of breath may also occur and sometimes no symptoms are present. In many cases, the first sign is a heart attack. Other complications include heart failure or an abnormal heartbeat. Risk factors include high blood pressure, smoking, diabetes, lack of exercise, obesity, high blood cholesterol, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
