Your Heartâs Electrical System how the heart’s electrical system works. electricity drives every beat of your heart sinoatrial node of the heart How the Heart Works how the heart’s electrical system works. heart beats sinoatrial node of the heart The heart’s electrical system sinoatrial node of the heart sinoatrial node of the heart Starting near the top of the heart sinoatrial node of the heart [National Heart, Lung, and Blood Institute] Your Heart's Electrical System "Your Heart's Electrical System" see the heart’s “pacemaker” in action In healthy hearts "Your Heart's Electrical System" The heart’s electrical system