Which wave on an EKG corresponds to peak ventricular depolarization?

The R wave is indeed the part of the EKG that corresponds to peak ventricular depolarization. In the context of an electrocardiogram (EKG or ECG), the QRS complex represents the overall process of ventricular depolarization, which is the electrical activity that leads to contraction of the ventricles. Within the QRS complex, the R wave is the tallest and most prominent wave, indicating the greatest amount of electrical activity as the ventricles fully depolarize.

During ventricular depolarization, electrical impulses travel through the ventricles, causing them to contract and pump blood to the lungs and the rest of the body. The R wave specifically reflects the moment when the largest mass of myocardial (heart muscle) cells depolarizes, hence it represents the peak of this activity within the QRS complex.

Understanding the EKG waves' relationship to cardiac events is crucial for interpreting heart rhythms and diagnosing conditions. The P wave reflects atrial depolarization, the T wave corresponds to ventricular repolarization, and while the QRS complex encompasses the entire process of ventricular depolarization, it is the R wave within that complex that marks the peak of depolarization activity.