In normal heart physiology, the sinoatrial (SA) node is responsible for initiating electrical impulses that regulate the heartbeat. These signals travel through the atria, reach the atrioventricular (AV) node, and proceed to the ventricles, leading to coordinated contraction — this is known as a sinus rhythm. However, when electrical activity arises from an abnormal site

The sinoatrial (SA) node is the natural pacemaker of the heart, initiating each heartbeat by generating electrical impulses. These signals cause the atria to contract and are then relayed to the ventricles through the AV node and Purkinje fibers. Any rhythm originating from the SA node is called a sinus rhythm. In this guide, we’ll

An electrocardiogram (ECG or EKG) is one of the most essential diagnostic tools in modern clinical medicine. It is a painless, non-invasive, and quick test that records the heart’s electrical activity through electrodes placed on the skin. An ECG plays a vital role in identifying heart rhythm disorders (arrhythmias), myocardial infarctions (heart attacks), electrolyte disturbances

Interpreting an ECG involves more than just identifying waves and segments—it also includes determining the heart’s rhythm and rate. Accurately calculating the heart rate from an ECG is critical for diagnosing conditions like tachycardia, bradycardia, arrhythmias, heart blocks, and more. In this guide, we’ll break down how to determine heart rate and rhythm from ECG