An ECG wave is defined as what?

• A. Complex
• B. Segment
• C. Wave
• D. Interval

Answer: (C)

An ECG wave is the deflection on the tracing produced by the heart’s electrical activity during a specific event. Each wave corresponds to a moment of electrical change, like atrial depolarization shown by the P wave or ventricular repolarization shown by the T wave. The QRS complex is a group of deflections (Q, R, and S) that together reflect ventricular depolarization, but it’s described as a complex because it’s a collection of waves. Segments are flat baseline portions between waves, and intervals are time spans from one reference point to another. So the term that best fits “an ECG wave” is the actual deflection itself on the trace—the wave.