Sistema de Condução do Coração e ECG, Animação. Alila Medical Media Português.

Help us produce more videos like this! Support us on Patreon and get free downloads and other great rewards: patreon.com/AlilaMedicalMedia Thank you very much! This video and other related images/videos (in high definition) are available for download under license here: https://www.alilamedicalmedia.com/-/g... Voiceover: Hermínio Matias; Translated by: Ana Vilela ©Alila Medical Media. All rights reserved. The heart's conduction system consists of the following components: Sinoatrial node, or SA node, located in the right atrium near the entrance to the superior vena cava. This is the heart's physiological pacemaker. It is responsible for the entire heartbeat and determines the heart rate. Electrical impulses from the SA node propagate through both atria and stimulate their contraction. - The atrioventricular node, or AV node, is located on the other side of the right atrium, near the atrioventricular valve. The AV node serves as an electrical gateway to the ventricles. It slows the passage of electrical impulses to the ventricles. This delay ensures that the atria have already expelled all the blood into the ventricles before they contract. The AV node receives signals from the SA node and sends them to the atrioventricular bundle—the bundle of His. This bundle is divided into two branches, the right bundle branch and the left bundle branch, which conduct the impulses to the apex of the heart. The signals are then sent to the Purkinje fibers, turning upward and propagating through the ventricular myocardium. The heart's electrical activity can be recorded in the form of an electrocardiogram, ECG, or EKG. An ECG is a composite recording of all the action potentials produced by nodes and myocardial cells. Each wave or segment of the ECG corresponds to a specific event in the cardiac electrical cycle. When the atria are filled with blood, the SA node fires, causing electrical signals to spread through the atria, causing them to depolarize. This is represented by the P wave on the ECG. Atrial contraction, or atrial systole, begins approximately 100 milliseconds after the onset of the P wave. The PQ segment represents the conduction time of the electrical impulse from the SA node to the AV node (AVN). The QRS complex marks the firing of the AV node and represents ventricular depolarization: The Q wave corresponds to depolarization of the interventricular septum The R wave is produced by depolarization of the main mass of the ventricles The S wave represents the last phase of ventricular depolarization at the base of the heart. Atrial repolarization also occurs during this time, but the signal is obscured by the large QRS complex. The ST segment reflects the plateau of the myocardial action potential. This occurs when the ventricles contract and pump blood. The T wave represents the repolarization of the ventricles immediately before ventricular relaxation, or ventricular diastole. This cycle repeats with each heartbeat. All images and videos from Alila Medical Media are for informational purposes only and are NOT intended to replace professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare provider with any questions you may have regarding a medical condition.