{"id":7413,"date":"2023-06-16T11:24:33","date_gmt":"2023-06-16T10:24:33","guid":{"rendered":"https:\/\/heart-explained.org\/?page_id=7413"},"modified":"2025-03-21T13:20:23","modified_gmt":"2025-03-21T13:20:23","slug":"your-hearts-electrical-system","status":"publish","type":"page","link":"https:\/\/heart-explained.org\/index.php\/your-hearts-electrical-system\/","title":{"rendered":"Your hearts electrical system"},"content":{"rendered":"<h5>Your heart: The basics<\/h5>\n<h1>Your heart&#8217;s electrical system<\/h1>\n<h2>What makes your heart beat?<\/h2>\n<p>Your heart is controlled by electrical signals that tell its muscles when to contract and when to relax.\u00a0<\/p>\n<p>Each pulse begins in the right atrium at the sino-atrial (SA) node. The SA node functions like a pacemaker, controlling your sinus rhythm (your heart\u2019s natural rhythm) and keeping your heart beating steadily and regularly.\u00a0<\/p>\n<p><b>Your heart&#8217;s electrical system<\/b><\/p>\n<p>\t\t\t\t\t<iframe loading=\"lazy\" \n    width=\"400\" \n    height=\"550\"\n    data-static=\"https:\/\/heart-explained.org\/wp-content\/uploads\/stats\/a\/electrical.gif\"\n    data-animated=\"https:\/\/heart-explained.org\/anims\/a_003\/electrical.html\"\n    src=\"https:\/\/heart-explained.org\/wp-content\/uploads\/stats\/a\/electrical.gif\"\n    frameborder=\"0\" \n    title=\"animation of a beating heart\"><br \/>\n<\/iframe><\/p>\n<p>The electrical pulse passes from the SA node through the heart to another node called the atrioventricular (AV) node, and then on down into the ventricles, causing them to contract.<\/p>\n<p>A normal pulse rate is 60 &#8211; 100 beats per minute. Of course, your heart will beat faster than that when you\u2019re exercising or stressed and slower when you\u2019re asleep.<\/p>\n<p>The heart\u2019s electrical activity can be measured and recorded using a machine called an electrocardiogram (an ECG or EKG &#8211; both abbreviations are commonly used).<\/p>\n<p><b>Normal ECG<\/b><\/p>\n<p>\t\t\t\t\t<iframe loading=\"lazy\" \n    width=\"400\" \n    height=\"75\"\n    data-static=\"https:\/\/heart-explained.org\/wp-content\/uploads\/stats\/a\/a_002_001.gif\"\n    data-animated=\"https:\/\/heart-explained.org\/anims\/002\/a_002_001.html\"\n    src=\"https:\/\/heart-explained.org\/wp-content\/uploads\/stats\/a\/a_002_001.gif\"\n    frameborder=\"0\" \n    title=\"animation of a beating heart\"><br \/>\n<\/iframe>\t\t\t\t<\/p>\n<p>An ECG produces a \u201ctracing\u201d, like the one above, that shows how your heart is behaving, and this can be used to diagnose heart disorders.<\/p>\n<p>To learn more about how the heart pumps blood around your body, take a look at <a href=\"https:\/\/heart-explained.org\/index.php\/how-your-heart-pumps\/\">How your heart pumps<\/a>.<\/p>\n<h2>A single heartbeat: Electrical pulses and an ECG<\/h2>\n<p>To get an understanding of how the heart\u2019s electrical system works it\u2019s easiest to look at just one heartbeat.<\/p>\n<p>The animation below shows how the electrical pulses flow from the SA node, which is up in the right atrium, down through the heart and all the way to the ventricles.\u00a0 In the inset box, we show the corresponding ECG tracing.<\/p>\n<p><b>Your heart in a single beat<\/b><\/p>\n<p>\t\t\t\t\t<iframe \n    width=\"400\" \n    height=550\n    data-static=\"https:\/\/heart-explained.org\/wp-content\/uploads\/stats\/a\/a_003_001.gif\"\n    data-animated=\"https:\/\/heart-explained.org\/anims\/a_003\/a_003_001.html\"\n    src=\"https:\/\/heart-explained.org\/wp-content\/uploads\/stats\/a\/a_003_001.gif\"\n    frameborder=\"0\" \n    title=\"animation of a beating heart\"><br \/>\n<\/iframe>\t\t\t\t<\/p>\n<p>The ECG line is broken down into a series of points: P, Q, R, S, and T.\u00a0 Each point represents a phase of the electrical pulse and each phase produces a different physical reaction in the muscles of the heart.<\/p>\n<p>Looking at our single heartbeat, this is what happens:<\/p>\n<p>The <strong>P-wave<\/strong> causes the atria to contract and push blood down into the ventricles.<\/p>\n<p>Then the <strong>Q-wave, R-wave, and S-wave<\/strong>, combined (the \u201cQRS complex\u201d), trigger the contraction of the ventricles, and this pushes blood out and around the body (from the left ventricle) and to the lungs (from the right ventricle).<\/p>\n<p>Finally, the <strong>T-wave<\/strong> neutralizes the charge held in the cells and allows the muscles to relax, ready for the next heartbeat.<\/p>\n<p>To learn more about how the heart pumps blood around your body, take a look at <a href=\"https:\/\/heart-explained.org\/index.php\/how-your-heart-pumps\/\">How your heart pumps<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Your heart: The basics Your heart&#8217;s electrical system What makes your heart beat? Your heart is controlled by electrical signals that tell its muscles when to contract and when to relax.\u00a0 Each pulse begins in the right atrium at the sino-atrial (SA) node. The SA node functions like a pacemaker, controlling your sinus rhythm (your [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"elementor_header_footer","meta":{"site-sidebar-layout":"no-sidebar","site-content-layout":"page-builder","ast-site-content-layout":"full-width-container","site-content-style":"unboxed","site-sidebar-style":"unboxed","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"disabled","ast-breadcrumbs-content":"","ast-featured-img":"disabled","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"class_list":["post-7413","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/heart-explained.org\/index.php\/wp-json\/wp\/v2\/pages\/7413","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/heart-explained.org\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/heart-explained.org\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/heart-explained.org\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/heart-explained.org\/index.php\/wp-json\/wp\/v2\/comments?post=7413"}],"version-history":[{"count":214,"href":"https:\/\/heart-explained.org\/index.php\/wp-json\/wp\/v2\/pages\/7413\/revisions"}],"predecessor-version":[{"id":16987,"href":"https:\/\/heart-explained.org\/index.php\/wp-json\/wp\/v2\/pages\/7413\/revisions\/16987"}],"wp:attachment":[{"href":"https:\/\/heart-explained.org\/index.php\/wp-json\/wp\/v2\/media?parent=7413"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}