cardiac physiology

Action Potential Heart Contraction

Posted on June 4, 2025 by anatomy

Action Potential Heart Contraction: A cardiac action potential initiates when the SA node fires, spreading electrical impulses that trigger calcium influx, leading to coordinated contraction of the atria and ventricles.

Blood Flow Relaxed Ventricles

Posted on May 25, 2025 by anatomy

Blood Flow Relaxed Ventricles: When the ventricles relax during diastole, blood flows passively from the atria into the ventricles through the open AV valves, preparing the heart for the next contraction.