Five phases of cardiac cycle & Atrial contraction

2619

0

HWC

1. Atrial contraction (atrial systole). 2. Isovolumetric (ventricular) contraction. 3. Ventricular ejection. 4. Isovolumetric (ventricular) relaxation. 5. Passive ventricular filling. Beginning of cardiac cycle • Prior to atrial contraction: • Atria and ventricles are relaxed. • Atrioventricular (AV) valves are open. • Semilunar (SL) valves are closed. • Atrial depolarization (P wave) triggers atrial contraction. • Causes atrial pressure to rise. • Pushes blood into the ventricles, raising ventricular pressure slightly. • Ventricular excitation (QRS wave) triggers ventricular contraction.

Share

Embed

Copy and paste this code into your website or blog.

Add To

You must login to add videos to your playlists.

Comments

0 Comments total

to post comments.

No comments have been posted for this video yet.