The Cardiovascular System

1. The Cardiovascular System Your Heart and Beyond

2. The Anatomy of the Heart • Located on the left side of the body above the diaphragm. The base of the heart is parallel to the right edge of the sternum. • The apex of the heart ( lowest point) is at the left mid-clavicular line and at the 5th intercostal space. • Important to know for CPR!

3. Placement of Heart

4. The Pump The heart consists of two pumps in one working together to send oxygen rich blood to the organs in the body.

5. Right The right pump – right atrium and ventricle – takes venous blood ( Low oxygenated blood) into the atrium and down to the ventricle and is “pumped” to the lungs to obtain oxygen.

6. LEFT • The left pump – left atrium and ventricle – takes blood with oxygen from the lungs and it is “pumped” to the entire body system.

7. The valves • The Tricuspid Valve – right side • The Mitral Valve – left side • Open during contraction of the atrium to allow blood flow to the ventricles. Close during the refilling of the atrium.

8. The heart is electric! • What causes the heart to pump? • The SA Node (sinoatrial) is a group of specialized heart cells that are self- excitatory. In other words, they have automaticity. • Automaticity means they require no stimulus and may excite themselves at will.

9. Spreading the wealth • 1)Impulse starts at the SA node • 2)Travels to the AV (atrioventricular) node • :sits at the lower part of right • atrium • 3)Travels down the Bundle of His • this breaks off into right and left • bundle branch which go to • apex of heart • 4) Travels to the Purkinje fibers • = ventricular contraction

10. Conduction of the heart

11. The heartbeat • The average adult heartbeat is 72 beats per minute. • Normal adult heartbeats are between 60-100 • Less than 60 = bradycardia • - Athletes, sleeping, medications, vagal nerve stimulation • Greater than 100 = tachycardia • - Fever, exercise, stress, caffeine, nicotine, • amphetamines

12. fibrillations • Atrial Fibrillation: the atriums of the heart are “ quivering” instead of beating. • - not immediately life threatening but can cause clots to form that travel to brain and cause a CVA (cerebral vascular accident) “stroke”

13. fibrillations • Ventricular Fibrillation: The ventricles of the heart are “quivering” instead of beating. • - Life threatening = Requires an immediate response! Needs “ shock” from defibrillator. • AED = Automatic Emergency Defibrillator.

14. Heart attacks • What happens during an “MI” ( Myocardial Infarction)? • - The heart is an organ that also requires oxygenated blood to keep functioning. • - Coronary arteries feed the heart the oxygenated blood and are positioned around the exterior of the heart.

15. The coronary arteries

16. Coronary circulation • The right coronary artery: Supplies blood to the right atrium, part of the left atrium, most of the right ventricle and the inferior part of the left ventricle. • The left coronary artery: Supplies blood to the left atrium and most of the left ventricle.

17. Myocardial Infarction • When a coronary artery becomes blocked, (embolus or plaque or both) the blood flow to that part of the heart stops. Cardiac tissue and muscle begins to die very quickly.

18. Myocardial infarction • It does hurt!!!!

19. Myocardial infarction

20. treatment • Cardiac Catheterization: Invasive procedure to find occluded artery and open the blockage with a stent.

21. stents

22. Be kind to your heart • You only have one!