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40 Cards in this Set
- Front
- Back
- 3rd side (hint)
Cardiovascular system is a closed system of the heart and blood vessels |
The heart pumps blood. Blood vessels allow blood to circulate to all parts of the body |
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Function of the cardiovascular system |
1. Deliver oxygen and nutrients to cells and tissues 2. Remove carbon dioxide and other waste products from cells and tissues |
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The heart |
1. A muscular organ about the size of a human fist 2. Located in the mediastinum, in the thoracic cavity between the lungs in the inferior mediastinum 3. The apex of the heart points to the left (inferior) 4. The base of the heart points toward the right (superior) |
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Cardiac muscle cells |
Striated, short, branched, fat, interconnected - one Central nucleus - numerous large mitochondria - sarcomeres - Z discs, A bands, and I bands - intercalated discs are connecting Junctions between cardiac cells that contain desmosomes ( holds cells together) and Gap Junctions ( allow ions to pass from cell to cell) |
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Pericardium |
1. Anchors the heart to the diaphragm 2. Three layers and one cavity: - pericardium, outer layer - serous pericardium, parietal and visceral - pericardial cavity 3. Pericardial fluid acts as a lubricant helping to reduce friction as the heart moves |
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Three layers of the heart wall |
1. Epicardium , outside layer, visceral pericardium, connective tissue layer 2. Myocardium, middle layer, thickest later, cardiac muscle 3. Endocardium, inner layer AKA endothelium |
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Pathway of blood through heart |
1. Inferior and superior vena cava 2. Right atrium 3. Tricuspid valve 4. Right ventricle 5. Pulmonary semilunar valve 6. Pulmonary trunk 7. Pulmonary arteries 8. Lungs (decreased carbon dioxide increase oxygen) 9. Pulmonary veins 10. Left atrium 11. Bicuspid valve 12. Left ventricle 13. Aortic semilunar valve 14. Ascending aorta 15. Aortic Arch 16. Descending aorta |
Veins 》 toward heart Arteries 》 away from heart |
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The two pumps of the heart |
1. Pulmonary pump - right side - pumps deoxygenated blood to pulmonary circuit and lungs 2. Systemic pump - left side - pumps oxygenated blood out to systemic circulation * deoxygenated and oxygenated blood never mix ** left ventricle pumps blood under higher pressure and is therefore more muscular |
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Systemic circulation |
1. Superior and inferior vena cava bring oxygen-poor, carbon dioxide rich blood to the right atrium 2. The superior venacava drains the upper body 3. The inferior vena cava drains the lower body 4. Superior and inferior vena cavae by the largest veins of the body |
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Pulmonary circulation |
Right ventricle 》 pulmonary trunk》 left and right pulmonary arteries 》 lungs 》 pulmonary capillaries 》 oxygen diffuses into the blood carbon dioxide diffuses out 》 oxygenated blood now travels through pulmonary veins to the left atrium |
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Coronary circulation |
1. Coronary Arteries supply the heart muscle 2. Left coronary artery supplies interventricular septum, anterior ventricle walls, left atrium, and posterior wall of left ventricle. 3. Right coronary artery supplies right atrium and most of right ventricle. Coronary veins: 1. Cardiac veins collect blood from capillary beds 2. Coronary sinus empties into right atrium |
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Heart Valves: control the flow of blood through the heart and ensure unidirectional blood flow through the heart |
1. Atrioventricular valves: prevent backflow into Atria when ventricles contract - lie between the atrium and ventricle on each side - bicuspid mitral valve (left AV valve) between the left atrium and left ventricle - tricuspid valve (thought AV valve) between the right atrium and right ventricle
2. Semi-lunar valves: prevent backflow from major arteries back into ventricle - between The ventricle and great vessel on each side - aortic semilunar valve between the left ventricle and aorta - pulmonary semilunar valve between the right ventricle and the pulmonary artery |
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Cardiac output (CO) |
1. The amount of blood pumped out of the left ventricle per minute 2. CO = HR x SV (stroke volume) Ex CO = 75 bpm × 70 ml/beat = 5250 ml/min = 5.25 L/min |
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Blood pressure |
The amount of pressure exerted on the walls of the vasculature. Determined by cardiac output, blood volume, and resistance to flow |
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Stroke volume |
1. Volume of blood pumped by each ventricle in one contraction (each heart beat) 2. About 70 mL of blood is pumped out of the left ventricle with each heartbeat |
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Effects of various factors on blood pressure |
1. Neural factors: the autonomic nervous system - sympathetic nervous system promotes narrowing of vessels or vasoconstriction - vasoconstriction increases blood pressure 2. Renal factors: the kidneys Renin》 Angiotensin II》 aldosterone 3. Temperature - heat has vasodilating effect - cold has vasoconstricting effect 4. Chemicals - epinephrine increases heart rate and blood pressure 5. Diet - diet low in salt, saturated fats, and cholesterol prevents hypertension |
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Variations in blood pressure |
1. Hypotension - low systolic below 100 mm HG - acute hypotension is a warning sign for circulatory shock 2. Hypertension - sustained elevated arterial pressure of 140/90 mm Hg |
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Conduction system of the heart |
1. Sinoatrial (SA) node: -Pacemaker, initiates mechanical contraction of the heart - generates the sinus rhythm measured by an EKG 2. Atrioventricular (AV) node: - after the impulse has traveled over the Atria, it reaches the AV node where there is a brief delay. This allows the Atria to complete their emptying into the ventricles 3. Bundle of His (AV bundle) 4. Right and left bundle branches - convey the impulses to the right and left ventricles respectively 5. Bachmann's bundle - branch is found in the left Atria . Purkinje fibers 6. Purkinje fibers- in contact with the myocardial muscle cells and stimulate the contraction of cardiac muscle fibers - in contact with the myocardial muscle cells and stimulate the contraction of cardiac muscle fibers EKG - record the heart's electrical activity - P wave represents depolarization of the Atria (Atria "on") - QRS complex represents depolarization of the ventricles and atrial repolarization (ventricles "on", Atria "off") - T wave represents the repolarization of the ventricles (ventricles "off")
SA node 》AV node 》bundle of HIS 》bundle branches 》purkinje fibers |
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Cardiac cycle and heart sounds |
1. Cardiac cycle refers to one complete heartbeat including systole and diastole - herpes approximately 75 times per minute - cardiac cycle length is normally 0.8 seconds 2. Mid-to-late diastole - pressure in heart is low 3. Ventricular systole - blood pressure Rises as ventricles prepared to contracted 4. Early diastole - at the end of systole all four valves are briefly closed at the same time Lub (S1) sounds occurring during ventricular systole due to the closing of the AV valves Dup (S2) sounds as a result of the closing of the semilunar valves during ventricular diastole Murmurs occur if there is a leakage or regurgitation, or a narrowing/ stenosis of one or more of these valves |
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Stroke volume |
The amount of blood ejected by the ventricles |
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Coronary sinus |
Receives deoxygenated blood from The myocardium |
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Internal carotid |
Supplies the brain with oxygenated blood |
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Sphygmomanometer |
Medical device used to measure blood pressure |
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EKG |
Medical device used to record electrical activity of the heart |
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Cardiac output |
The amount of blood pumped by heart per minute |
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Tachycardia |
Abnormally fast heart rate |
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End-diastolic volume |
After contraction, the blood remaining in the ventricles |
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Interventricular septum |
This structure separates the right and left ventricles |
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Myocarditis |
Inflammation of the myocardium |
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Pulmonary circulation |
Blood flow from the heart to the lungs and back to the heart |
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What would happen to heart function with an occluded left coronary artery |
The left ventricle would fail to work properly or at all. Aka the Widowmaker |
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Preload |
Amount of tension in ventricles immediately before contraction |
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Afterload |
Pressure that ventricles must overcome to eject blood |
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What is occurring when the semilunar valves are open |
AV valves are closed, ventricles are in systole, blood enters aorta, blood enters pulmonary arteries |
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What is the portion of the intrinsic conduction system located in the superior interventricular septum |
The AV bundle |
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An ECG provides information about what |
Movement of the excitation wave across the heart |
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What is the sequence of contraction of the heart chambers |
Both Atria followed by both ventricles |
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The fact that the left ventricle wall is thicker than the right reveals what |
Pumps blood against greater resistance |
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What does the chordae tendineae do |
Prevents the AV valve flaps from everting |
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Freshly oxygenated blood is first received by |
The left atrium |
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