Pulseless electrical activity (PEA) is defined as the presence of organized electrical conduction on cardiac monitoring (normal-appearing QRS complexes with P and T waves) in the clinical absence of a palpable pulse, distinguishing it mechanistically from cardiac arrest rhythms like ventricular fibrillation or tachycardia because treatment requires identifying and correcting the underlying cause rather than a uniform intervention. PEA is theoretically divided into two mechanisms: the "empty heart" form, in which conduction and contraction are both normal but the heart lacks sufficient blood volume to fill and eject (due to hypovolemia or obstructive processes such as tamponade or tension pneumothorax), and electromechanical dissociation (EMD), in which normal cardiac action potentials occur but fail to produce effective mechanical contraction, typically due to systemic metabolic derangement impairing the greater energy demand of contraction relative to conduction. This is a topic in emergency medicine/cardiac resuscitation physiology, relating electrical-mechanical coupling of the heart to the differential diagnosis of cardiac arrest.
Pulseless electrical activity (PEA) is defined as the presence of organized electrical conduction on cardiac monitoring (normal-appearing QRS complexes with P and T waves) in the clinical absence of …