This irregular heartbeat is created by a
disruption in a web of nerves covering the surface of the heart. These nerves
send electrical signals that cause your heart to contract and pump blood out of
An enlarged heart (cardiomegaly) may have various causes. But it's usually the result of high blood pressure (hypertension) or coronary artery disease.
An enlarged heart may not pump blood effectively, resulting in congestive heart failure. Cardiomegaly may improve over time. But most people with an enlarged heart need lifelong treatment with medications.
This web of nerves is controlled by a collection of
cells on the right atrium called the sinoatrial node. As it fires, so do the
rest of the nerves, causing all of the muscle cells in your heart to contract,
producing one forceful pump.
As mitral valve stenosis or MR
stretches out your heart, it too can disrupt this web of nerves. Communication
pathways may weaken because the sinoatrial node is no longer working correctly.
Without clear signals from this node, the nerves begin to fire randomly,
creating a chaotic network of electrical signals. When this happens, the heart
is no longer able to pump with one motion, and instead it starts beating
Atrial fibrillation is the most common arrhythmia that stems from mitral valve
stenosis and MR. If you have atrial fibrillation, you will have treatment to control or stop the irregular rhythm.
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Institute via the Internet web site at http://
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WebMD Medical Reference from Healthwise
March 12, 2014
This information is not intended to replace the advice of a doctor.
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