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The primary purpose of a pacemaker is to maintain an even heart rate, either because the heart's natural cardiac pacemaker provides an inadequate or irregular heartbeat, or because there is a block in the heart's electrical conduction system. Modern pacemakers are externally programmable and allow a cardiologist to select the optimal pacing ...
The cardiac pacemaker is the heart's natural rhythm generator. It employs pacemaker cells that produce electrical impulses, known as cardiac action potentials, which control the rate of contraction of the cardiac muscle, that is, the heart rate. In most humans, these cells are concentrated in the sinoatrial (SA) node, the primary pacemaker ...
Basic cardiac action potential. Unlike the action potential in skeletal muscle cells, the cardiac action potential is not initiated by nervous activity.Instead, it arises from a group of specialized cells known as pacemaker cells, that have automatic action potential generation capability.
Pacemakers are also sometimes used temporarily when someone is recovering from a heart attack or heart surgery, but in this case only the wires are inserted into the body; the pacemaker box stays ...
The pacemaker current (I f, or I Kf, also called funny current) is an electric current in the heart that flows through the HCN channel or pacemaker channel. Such channels are important parts of the electrical conduction system of the heart and form a component of the natural pacemaker .
In a healthy heart, the SA node continuously produces action potentials, setting the rhythm of the heart (sinus rhythm), and so is known as the heart's natural pacemaker. The rate of action potentials produced (and therefore the heart rate) is influenced by the nerves that supply it. [2]
Other forms of cardiac pacing are transvenous pacing, epicardial pacing, [5] and permanent pacing with an implantable pacemaker. In addition to synchronized transcutaneous pacing offered by newer cardiac monitor/defibrillators, there is also an option for asynchronous pacing.
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