the cardiac cycle n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
The Cardiac Cycle PowerPoint Presentation
Download Presentation
The Cardiac Cycle

Loading in 2 Seconds...

play fullscreen
1 / 8

The Cardiac Cycle - PowerPoint PPT Presentation


  • 192 Views
  • Uploaded on

The Cardiac Cycle. Cardiac Cycle. The cardiac cycle is one complete heart beat – a contraction and relaxation of each heart chamber; 1 cycle = 0.8s 2 basic phases: Diastole: ventricles relax to fill with blood Systole: Ventricles contract to push blood into arteries.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'The Cardiac Cycle' - donar


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
cardiac cycle
Cardiac Cycle
  • The cardiac cycle is one complete heart beat – a contraction and relaxation of each heart chamber; 1 cycle = 0.8s
  • 2 basic phases:
    • Diastole: ventricles relax to fill with blood
    • Systole: Ventricles contract to push blood into arteries
summary of events in c ardiac cycle
Summary of Events in Cardiac Cycle

1) Atria are relaxed and fill with blood

2) Atria contract and force blood into the ventricles through the AV valves

3) Ventricles contract forcing AV valves shut and SL valves open; blood moves into arteries

4) Ventricles relax, causing SL valves to snap shut

heart sounds
Heart Sounds
  • Lubb-DUBB sound is caused by closing of AV and SL valves
    • “Lubb” caused by closing of AV valves; double sound because left valve closes slightly before right
    • “DUBB” caused by closing of SL valves
  • When valves do not close properly, can hear sound of blood leaking through when valves shut = heart murmur
activity listening to heart sounds
Activity: Listening to Heart Sounds
  • Using a stethoscope, listen to the lubb-DUBB sound of your heart
    • Where do you notice the clearest sound?
    • Compare sitting vs. standing
  • Compare normal and abnormal heart sounds
    • http://depts.washington.edu/physdx/heart/demo.html
heart rhythm
Heart Rhythm
  • Heart beats on it’s own, without input from the brain
  • A cluster of nerve cells in the right atrium, called the sinoatrial (SA) node, generate electrical impulses and set the rhythm for the heart
    • SA node causes atria to contract, and stimulates AV node
    • AV node and Purkinje fibers cause ventricles to contract
observing heartbeats electrocardiographs
Observing Heartbeats: Electrocardiographs
  • An electrocardiograph is a machine that detects electrical signals from the heart and records them as an electrocardiogram.

P wave: atrial contraction

QRS complex: ventricular contraction

T wave: recovery from contraction

heart abnormalities
Heart Abnormalities
  • Murmurs – improper valve closing
  • Stenosis – narrowing of blood vessel (pulmonary or aortic), causes enlargement of one ventricle
  • Septal defects – hole between atria or hole between ventricles (allows oxy and deoxy blood to mix)