A student nurse is reviewing for an upcoming examination and recognizes in the ECG readings that the QRS wave represents which of the following?

Choice A rationale

Atrial depolarization refers to the electrical activation of the atria, which is depicted by the P wave on an ECG, not the T wave. The P wave represents the contraction phase of the atria as it pumps blood into the ventricles. Therefore, this option is incorrect for the T wave.

Choice B rationale

Atrial repolarization is the process of the atria returning to their resting state. This repolarization is generally obscured by the QRS complex on an ECG and is not associated with the T wave. Thus, this answer choice is also incorrect.

Choice C rationale

Ventricular depolarization is represented by the QRS complex on an ECG. It indicates the ventricles are contracting to pump blood to the lungs and the rest of the body. Therefore, it does not correlate with the T wave.

Choice D rationale

Ventricular repolarization is indicated by the T wave on an ECG. This phase signifies the ventricles returning to their resting state after the contraction. It is the correct answer as it accurately reflects the T wave's function.

Choice A rationale

An elliptical chest describes the typical shape of a healthy chest with a lateral dimension greater than the anteroposterior dimension. This shape allows for normal expansion and contraction of the lungs during breathing. An elliptical chest does not indicate any deformity or abnormality in the sternum or costal cartilage.

Choice B rationale

Pectus excavatum, also known as funnel chest, is a congenital deformity where the sternum and costal cartilage are sunken inward, creating a concave appearance of the chest. This condition can range in severity and may affect respiratory function and exercise tolerance in some individuals. Surgical correction may be considered for severe cases.

Choice C rationale

A standard chest describes a chest without any deformities or abnormalities, typically with a normal elliptical shape. This term does not denote any specific condition or configuration and implies a healthy, non-deformed chest.

Choice D rationale

Barrel chest is characterized by an increased anteroposterior diameter of the chest, giving it a round or barrel-like appearance. This condition is often seen in individuals with chronic obstructive pulmonary disease (COPD) or emphysema, where the lungs are chronically overinflated, causing the chest to expand and lose its normal shape.