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This process is of vital importance as it allows for the heart to beat in a controlled manner, without the need for conscious input. EC coupling results in the sequential contraction of the heart muscles that allows blood to be pumped, first to the lungs ( pulmonary circulation ) and then around the rest of the body ( systemic circulation ) at ...
A transthoracic echocardiogram (TTE) is the most common type of echocardiogram, which is a still or moving image of the internal parts of the heart using ultrasound.In this case, the probe (or ultrasonic transducer) is placed on the chest or abdomen of the subject to get various views of the heart.
Ectopic beat is a disturbance of the cardiac rhythm frequently related to the electrical conduction system of the heart, in which beats arise from fibers or group of fibers outside the region in the heart muscle ordinarily responsible for impulse formation (i.e., the sinoatrial node).
The action potentials of cardiac muscle are unusually sustained. This prevents premature relaxation, maintaining initial contraction until the entire myocardium has had time to depolarize and contract. Absence of tetany. After contracting, the heart must relax to fill up again.
Cardiac physiology or heart function is the study of healthy, unimpaired function of the heart: involving blood flow; myocardium structure; the electrical conduction system of the heart; the cardiac cycle and cardiac output and how these interact and depend on one another.
Calcium is a vital element for regulating the contraction and relaxation of the heart muscle. [6] Calcium sensitizers are medications that increase the responsiveness of heart muscle cells to calcium, enabling more forceful contractions while conserving energy. [ 49 ]
In a healthy heart all activities and rests during each individual cardiac cycle, or heartbeat, are initiated and orchestrated by signals of the heart's electrical conduction system, which is the "wiring" of the heart that carries electrical impulses throughout the body of cardiomyocytes, the specialized muscle cells of the heart.
These calcium ions are responsible for the contraction of the heart. Calcium also activates chloride channels called I to2 , which allow Cl − to enter the cell. Increased calcium concentration in the cell also increases activity of the sodium-calcium exchangers, while increased sodium concentration (from the depolarisation of phase 0 ...