What is characterized by "pulseless electrical activity" on the EKG?

Pulseless electrical activity (PEA) is a clinical condition where there is organized electrical activity seen on the electrocardiogram, but this is not accompanied by effective mechanical contraction of the heart, resulting in the absence of a palpable pulse. In this scenario, the heart's electrical system may appear normal—showing well-defined rhythms like sinus rhythm or other organized patterns—yet the heart is not actually pumping blood effectively.

This phenomenon can occur in several situations, including severe hypovolemia, cardiac tamponade, tension pneumothorax, or significant myocardial ischemia. However, the defining characteristic of PEA is the discrepancy between the electrical activity monitored on the EKG and the failure of the heart to generate a pulse due to mechanical dysfunction. Understanding this distinction underscores the vital importance of both electrical and mechanical functions of the heart in maintaining circulation and the need for immediate medical intervention when PEA is identified.