Health Bible

Most arrhythmias (abnormal heartbeats) neither cause symptoms nor interfere with the heart’s ability to pump blood. Thus, they usually pose little or no risk. They can cause considerable anxiety if a person becomes aware of them. There are some arrhythmias, harmless in themselves that can lead to more serious arrhythmias.

Any arrhythmia that impairs the heart’s ability to pump blood adequately is serious. How serious, depends in part on where the arrhythmia originates. Is it in the heart’s normal pacemaker, in the atria, or in the ventricles? Generally, arrhythmias which originate in the ventricles are more serious than those that originate in the atria. These are more serious than those that originate in the pacemaker. However, there are many exceptions.

The myocardium is the muscular wall of the heart, or the heart muscle. It contracts to pump blood out of the heart, and then relaxes as the heart refills with returning blood. The myocardium’s smooth outer membrane is called the epicardium. Its inner lining is called the endocardium.

Myocarditis is an inflammation of the myocardium. When the heart becomes inflamed, it Is unable to pump as well because of damage to its cells and swelling (edema). The heart muscle may be damaged even more if the body’s immune system sends antibodies to try to fight whatever started the inflammation. Sometimes, these antibodies attack the tissues of the heart instead. If too many heart muscle cells are damaged, the heart muscle becomes weakened. In some cases, this process happens very quickly and results in heart failure or even sudden death.