R-on-T Phenomenon — ECG Academy Lesson

Understand the vulnerable period of repolarization, recognize when a PVC falls on the T wave, and learn why R-on-T is a high-priority finding requiring immediate notification.

Learning Objectives

• Explain the vulnerable period of ventricular repolarization and its relationship to the T wave
• Identify the R-on-T phenomenon on a rhythm strip
• Describe why R-on-T can trigger ventricular tachycardia or ventricular fibrillation
• Articulate the appropriate monitor tech response to an R-on-T event
• Differentiate R-on-T from other PVC timing patterns