Doctor's Notes on Arrhythmias (Heart Rhythm Disorders)
Arrhythmias are abnormal heartbeats. There are many types of arrhythmias, and they are sometimes classified by where they begin in the heart (the atria, AV node, or the ventricles). They may also be classified as one of four types - premature beats, supraventricular, ventricular, and bradyarrhythmias. Ventricular fibrillation and ventricular tachycardia are types of arrhythmias that can lead to death in minutes.
In many cases, arrhythmias cause minimal to no symptoms but in other cases, people can feel the arrhythmia when it happens. Symptoms of arrhythmias include palpitations, feeling "skipped beats," thumping or fluttering in the chest, a sensation of the heart racing, feeling faint or tired, lightheadedness or fainting, shortness of breath, and chest pain or discomfort. Many of these same symptoms may be due to anxiety, stress, or causes other than an abnormal heartbeat.
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In the U.S., 1 in every 4 deaths is caused by heart disease.
See AnswerREFERENCE:
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.