The atria, the heart’s upper chambers, and ventricles, the heart’s lower chambers, work together to pump blood through the heart by alternately contracting and relaxing. The heart’s electrical system is the power source that makes this possible, and its natural pacemaker regulates normal rhythms. When your heart is beating normally, you usually don’t notice it. But when it beats irregularly or abnormally – called an arrhythmia – you may become all too aware of each and every beat.
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In this white board session, Patrick J. Tchou, MD, Associate Section Head of the Section of Electrophysiology and Cardiac Pacing in the Department of Cardiovascular Medicine, uses helpful diagrams and explanations to make sense of terms such as arrhythmia, tachycardia and supraventricular — which really aren’t as complicated as they sound.