The Mammalian Heart

Life in the ER https://www.youtube.com/watch?v=gVY04NQUpxk

How well do you know the heart? How big is your heart? T or F Tetanus (maintained contraction) does not occur in cardiac muscle T or F The Heart beats about 1,000 times a day T or F All mammals have a 4 chambered heart T or F The beating of the heart is an involuntary action

Location of the Heart Describe location Apex Tip of heart Found in the center of the chest with the tip of the heart on the left side

Pericardium Thin membrane covers the heart Filled with pericardial fluid (protection) Shock absorption

General Structure of the Heart 4 Chambers Two atria (upper) Two ventricles (lower) 4 valves 2 major arteries and 3 major veins

Blood Vessels Arteries Veins Take blood away from the heart Bring blood toward the heart Carotid Artery blood spurts out because it is pushed out from the force of your heart beating Jugular veins (internal and external)

Blood Flow https://www.youtube.com/watch?v=KSbbDnbSEyM Summarize the flow of blood through the heart

Heart Vales Bicuspid (Mitral) valve Tricuspid valve Aortic valve Pulmonary valve

Blood Flow Through the Heart Upper Body Deoxygenated Blood Lungs Oxygenated Blood Lungs Oxygenated Blood Deoxygenated Blood Lower body

Blood Flow Through the Heart Upper Body Deoxygenated Blood Lungs Lungs Deoxygenated Blood

Blood Flow Through the Heart Upper Body Lungs Oxygenated Blood Lungs Oxygenated Blood Lower body

The Aorta

Heart Sounds https://www.youtube.com/watch?v=riDPxasIz_I Valves Prevent a backflow of blood “Lub” Pulmonary and aortic valves “ Strong Push” “Dub” Bicuspid (mitral) and tricuspid valves “Reloading push”

Brainpop When is blood pressure the highest? During diastole the heart is in which type of state? If you have hypertension, you are at a greater risk for which disease? What are some factors that lead to hypertension? What are some factors that lead to high blood pressure

Blood Pressure http://www.youtube.com/watch?v=BeAYjETW-7Y Why is blood pressure important? Low #’s Indicate dysfunction High #’s Indicate future disease Blood has to overcome the osmotic and physical pressure at the capillary level

Phases of a Heart Beat Systole (sis-toll-e) Contraction of ventricles Diastole (die-as-toll-e) Relaxation of ventricles

Blood Pressure Systolic (sis-tolic) Number at which you hear the heart Diastolic (dye-a-stolic) Number at which you no longer hear the heart Diastolic the pressure the arties place on blood Diastolic pressure is the pressure the pipes exert on water Systole in your house water does not flow, it comes out in spurts. Because there is more pressure and more volume Higher pressure

According to the. . . . American Heart Association High blood pressure 140/90 Low blood pressure 90/45

Add Purkinje’s Fibers to heart WS!!!! Conduction System of the Heart https://www.youtube.com/watch?v=te_SY3MeWys The process SA Node AKA pacemaker ________________ AV bundle AKA Bundle of His SA node is called the pacemaker because it sets the rhythm for the contraction of the heart, it fires action potentials at a rate of 100/min Neurotransmitters and hormones can slow this down or speed it up The firing of action potentials is what causes the heart to beat Damage ultimately results in low heart rate, low BP and inadequate O2 to the brain Add Purkinje’s Fibers to heart WS!!!!

How do you read this thing???

How to take blood pressure https://www.youtube.com/watch?v=Gmic13mvsgo

Electrocardiogram https://www. youtube. com/watch Diagnoses abnormalities Depolarization: Repolarization: Waves of heart beat: P wave Atrial Depolarization QRS Complex Ventricular depolarization T wave Repolarization of ventricles Right after P wave begins the atria contract, depolarization = contraction, repolarization = relaxation

The Artificial Pace Maker https://www.youtube.com/watch?v=WNN4Fw2EWxI https://www.youtube.com/watch?v=SMXBR_YFocs

The Cardiac Cycle Relaxation Atrial systole Ventricular systole All chambers in diastole Valves open Ventricles fill with blood Atrial systole Atria contract Ventricular systole Ventricles contract Atria contract to move the last of the blood into the ventricles

What is Fibrillation? Fib-rill-la-shon The heart quivers Fibers not contracting together Blood not being pumped A Fib Atria not contracting V Fib Ventricles not contracting

What is Long QT Syndrome. https://www. youtube. com/watch Distance between S-T wave is greater than .4 sec When can this happen? During the vulnerable period of repolarization Can be caused by sudden force/impact to chest during vulnerable period

What’s Wrong With My Patient? Treat the patient not the rhythm Identify the P wave, QRS complex and T wave Look for pattern Get Patients HR Tachycardia HR greater than 100 Bradycardia HR less than 60

Blood Pressure Review Why is the systolic reading higher than the diastolic reading? Which type of blood vessel has a higher average blood pressure? Why? During systole the ventricles are contracted and push blood out of the heart Arteries have a higher average blood pressure because they are “pushing” blood out of the heart

Cardiac Output (CO) Amount of blood the heart pumps per min Normal 5 to 6 L/min

Calculating Cardiac Output Determined by: Stroke volume (SV) Heart rate (HR) CO = HR X SV/1,000

Determining Cardiac Output Heart Rate: 60 bpm, Stroke Volume: 70 mL Herat Rate: 55 bpm, Stroke Volume: 60 mL Heart Rate: 85 bpm, Stroke Volume: 90 mL Heart Rate: 140 bpm, Stroke Volume: 100 mL Heart Rate: 160 bpm, Stroke Volume: 120 mL Explain why stroke volume is higher when someone is standing up than when someone is laying down. When would cardiac output increase? Why? What factors effect cardiac output?

The Mysterious Human Heart http://www. pbs How was Kevin’s disorder treated with technology? What did Dr. Zipes mean by the phrase “umbilical cord attached to medical therapy”? What are pacemakers? How have they evolved? What are the pros and cons of living with a pacemaker?