What does the QRS complex indicate in an EKG?

The QRS complex on an EKG represents the electrical activity associated with the contraction of the ventricles, also known as ventricular depolarization. This occurs when the electrical impulses travel through the ventricles, causing them to contract and pump blood out to the lungs and the rest of the body. The QRS complex is typically measured from the beginning of the Q wave to the end of the S wave and is characterized by a sharp, steep peak, signifying the rapid depolarization of the ventricles.

Each component of the EKG wave serves a specific purpose; while the P wave indicates atrial depolarization (the electrical activity leading to atrial contraction), the QRS complex is focused solely on the ventricles. Understanding the role of the QRS complex is crucial for interpreting an EKG, as it provides important information about the heart's electrical conduction system and overall cardiac function.