Search results
Results from the WOW.Com Content Network
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 ...
The cardiac action potential has five phases. I to1 is active during phase 1, causing a fast repolarization of the action potential. The cardiac transient outward potassium current (referred to as I to1 or I to [1]) is one of the ion currents across the cell membrane of heart muscle cells.
Ross and Glomset initially proposed that endothelial cell uncovering was the first step in the development of atherosclerosis. [2] Other hypotheses have associated the role of infectious agents (e.g. cytomegalovirus, Chlamydia pneumoniae and Helicobacter pylori) in inflammatory responses in the arterial wall. [3]
Heart health is a long-time pain point for Americans—physically and emotionally. Heart disease is the leading cause of death in the U.S., and that number crosses sex, racial and ethnic lines ...
An increase in sympathetic stimulation to the heart increases contractility and heart rate. An increase in contractility tends to increase stroke volume and thus a secondary increase in preload. An increase in preload results in an increased force of contraction by Starling's law of the heart; this does not require a change in contractility.
HDL cholesterol is “good” cholesterol and high levels of it can lower the risk of heart disease and stroke. ... Dr. Bereliani emphasizes that high cholesterol does not equal heart disease ...
An artificial cardiac pacemaker (or artificial pacemaker, so as not to be confused with the natural cardiac pacemaker) or just pacemaker is an implanted medical device that generates electrical impulses delivered by electrodes to the chambers of the heart either the upper atria, or lower ventricles to cause the targeted chambers to contract and ...
The heart muscle may become inflamed in a condition called myocarditis, [46] most commonly caused by a viral infection [47] but sometimes caused by the body's own immune system. [48] Heart muscle can also be damaged by drugs such as alcohol, long standing high blood pressure or hypertension, or persistent abnormal heart racing. [49]