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The degree of binding depends upon the concentration of calcium ions in the cell. Within an in vivo intact heart, the action/response of the sympathetic nervous system is driven by precisely timed releases of a catecholamine , which is a process that determines the concentration of calcium ions in the cytosol of cardiac muscle cells.
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.
A slow heart rate of 60 or less beats per minute is defined as bradycardia. A fast heart rate of more than 100 beats per minute is defined as tachycardia. An arrhythmia is defined as one that is not physiological such as the lowered heart rate that a trained athlete may naturally have developed; the resting heart rates may be less than 60 bpm.
For healthy people, the Target Heart Rate (THR) or Training Heart Rate Range (THRR) is a desired range of heart rate reached during aerobic exercise which enables one's heart and lungs to receive the most benefit from a workout. This theoretical range varies based mostly on age; however, a person's physical condition, sex, and previous training ...
Major factors influencing cardiac output – heart rate and stroke volume, both of which are variable. [1]In cardiac physiology, cardiac output (CO), also known as heart output and often denoted by the symbols , ˙, or ˙, [2] is the volumetric flow rate of the heart's pumping output: that is, the volume of blood being pumped by a single ventricle of the heart, per unit time (usually measured ...
Heart disease is a type of cardiovascular disease that affects the heart’s structure and function. Several different heart conditions fall under the umbrella term for heart disease.
The recommended daily amount of magnesium depends on your age, Derocha says, but generally adult men should aim for 400-430 milligrams per day while adult women should try to get 310-320 ...
The action potential passes along the cell membrane causing the cell to contract, therefore the activity of the sinoatrial node results in a resting heart rate of roughly 60–100 beats per minute. All cardiac muscle cells are electrically linked to one another, by intercalated discs which allow the action potential to pass from one cell to the ...