New answers tagged cardiology
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The vagus nerve controls heart rate. This is the best example of a direct nerve action potential impacting cardiac muscle, although one could argue the adrenaline system to be an indirect mechanism.
The vagus nerve is part of the parasympathetic system, it acts to decrease heart rate. Resting heart rate is maintained by permanent vagal stimulation/tone by ...
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Coronary artery disease thickens the wall. Flow is dramatically affected by thickness (radius to the fourth power). In an echo you observe the heart muscle i.e. does it contract normally using the surrounding muscle and baseline as a comparison. If the wall is thickened, this will cause a decrease in perfusion which will result in the heart muscle ...
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A number of things can be seen. Ischaemia is typically caused by the narrowing of blood vessels that prevents perfusion (blood flow) to the heart or other organs. When the heart muscle doesn't get enough oxygen, the walls of the heart might not "beat" (i.e. contract) properly. We observe this and thus can tell if a coronary artery is reduced or blocked or ...
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