Module 1: Cardiac Muscle And Hemodynamics Flashcards

Question

What are the process of cardiac myocyte contraction?

Answer 1

1. Voltage-gated Nat channels open. 2. Na+ inflow depolarizes the membrane and triggers the opening of still more Nat channels, creating a positive feedback cycle and a rapidly rising membrane voltage. 3. Na+ channels close when the cell depolarizes, and the voltage peaks at nearly +30 mV. 4. Ca2+ entering through slow Ca2+ channels prolongs depolarization of membrane, creating a plateau. Plateau falls slightly because of some K+ leakage, but most K+ channels remain closed until end of plateau. 5. Ca?+ channels close and Ca?* is transported out of cell. K* channels open, and rapid K* outflow returns membrane to its resting potential.

Answer 2

1. Non-Contractile (nodal) cells have to stop action potential generation • Causes the action potential to stop in within contractile cells 2. Calcium (Ca2+) ions must be pumped from the sarcoplasm back into the Sarcoplasmic Reticulum and/or ECF • Calcium ATPase pump on the sarcolemma • Sodium – Calcium Exchanger • SERCA Pump — Sarco/endoplasmic reticulum Calcium (Ca 2+) ATPase

Answer 3

• The intensity of cardiac muscle contractility correlates directly with the intracellular Calcium (Ca 2+) concentration — This depends on the amount of Calcium (Ca2+) released from sarcoplasmic reticulum stores • What influences the release of Calcium (Ca2+) ions from the sarcoplasmic reticulum? — Size of the inward calcium (Ca2+) ions during the plateau of the myocardial action potential — Amount of calcium (Ca2+) ions previously stored in the sarcoplasmic reticulum for release

Answer 4

The magnitude of the tension developed by myocardial cells is proportional to the intracellular calcium (Ca2+) ion concentration.

Answer 5

1. Chronotropic • Affect the heart rate and rhythm • Affecting the electrical conduction system of the heart and the nerves that influence it (Specifically, the SA node). 2. Dromotropic • Alters the rate action potentials are conducted from the atria to the ventricles • Affects the conduction speed thru the AV node 3. Inotropic • Alters the force of muscular contractions • Myocytes have more contractility force

Answer 6

SY MPATHETIC NERVOUS SYSTEM EFFECT Positive Chronotropic Effects • Increases the heart rate • Norepinephrine (SNS) activates β1 Adrenergic Receptors in the SA node • Increases rate of depolarization in nodal cells • Increases rate of action potential formation Positive Dromotropic Effects • Increase in conduction velocity through the AV node • Increase of action potential speed through the AV node Positive Inotropic Effects • Increases the strength of contractility in the Atria and Ventricles • Influences the amount of calcium ions in the sarcoplasm PARASYMPATHETIC NERVOUS SYSTEM EFFECTS Negative Chronotropic Effects • Decreases the heart rate • Acetylcholine released from parasympathetic nerve fibers activates muscarinic (M 2) receptors in the SA node • Decreases rate of depolarization in nodal cells • Overall decreases rate of action potential formation Negative Dromotropic Effects • Decrease in conduction velocity through the AV node • Decrease of action potential in the AV node

Answer 7

• Antagonistic receptor blockers • Agonistic receptor blockers • Positive and negative chronotropic medications • Positive and negative dromotropic medications • Positive and negative inotropic medications • Calcium Channel Blockers • Beta Blockers

Answer 8

• Cardiac Conduction System (CCS) allows the heart to beat in an organized and coordinated pattern — Coordinates myocyte contraction activity • CCS generates the electrical impulse (action potential) and transmit it through the heart in a specific order/direction

Answer 9

Sinoatrial Node (SA Node) • Pacemaker- determines heart rate • Cells spontaneously depolarize and undergo action potentials • Action potential travels through the CCS and myocytes • Sets the rhythm and rate of heart • Influenced by ANS and various chemicals/drugs Atrioventricular Node (AV Node) • Sends signal (AP) to the ventricles • Slows it down for moment • Serves as an electrical relay system receiving electrical impulse form SA Node • Slows the electrical impulse down before allow it to pass through the interventricular bundle Atrioventricular Bundle (AV Bundle / Bundle of His) • Right and Left Bundle branches • Pass the electrical impulse down the interventricular septum and to the lateral walls of the ventricles Purkinje Fibers • Carry the electrical signal from bundle branches to the myocardium

Answer 10

• Speed at which action potentials are propagated within the tissue • Determines how long it takes the action potential to spreads throughout the myocardium • Conduction velocity differs in areas of the heart

Answer 11

• Measurement of tiny potential differences on the surface of the body that reflect the electrical activity of the heart beating • Seriously- graphing out the electrical activity of the heart over time

Answer 12

• Heartrate — Normal, slow, fast • Rhythm — Sinus rhythm or irregular rhythm • Myocyte damage • Nodal dysfunction

Answer 13

P Wave - Atrial Depolarization QRS Complex - Ventricular Depolarization T Wave - Ventricle Repolarization PQ (PR) Segment - Atrial contraction ST Segment - Ventricular contraction

Answer 14

Normal heartbeat Three criteria must be met 1. AP must originate in the SA node 2. SA nodal impulses must occur regularly at a rate of 60–100 impulses per minute 3. The activation of the myocardium must occur in the correct sequence and with the correct timing and delays

Answer 15

• Cardiac conduction system does not work properly • Causes to heart to contract abnormally: too fast, too slow, irregular • Can be identified on an EKG

Answer 16

B. Contraction of the ventricle myocytes

Answer 17

C. Purkinje fibers

Answer 18

B. Chronotropic

Answer 19

C. Calcium ions entering the cell are associated with with phase 1 of the action potential

Answer 20

Must remove calcium from sarcoplasm via Calcium ATPase pump, Sodium – Calcium Exchanger, and SERCA

Answer 21

It would shorten or lengthen the contraction time, respectively

Answer 22

• Sodium: phase 4 • Calcium: phase 0 • Potassium: phase 3

Answer 23

The rate of spontaneous depolarization determines heart rate

Answer 24

• A. Sodium ions in • B. Potassium ions out • C. Calcium ions in/Potassium ions out • D. Potassium ions out • E. RMP

Answer 25

Positive calcium ions are moving in; Positive potassium ions are moving out; Calcium ions moving in stimulate muscle contraction

Answer 26

Gap junctions allow for positive ions to move from one myocyte to another allow for initiation of an action potential

Answer 27

B. The aortic valve contains chordae tendineae

Answer 28

Prevent backflow of blood through the heart

Answer 29

Allow for the movement of ions from one cardiac muscle cell to another- creating the ability to transfer the propagation of an action potential

Answer 30

• Physical factors that govern blood flow in the cardiovascular system • Physiology that pertains to the circulation of blood • Physics is the same as movement of fluids in general • Concepts of blood flow, pressure, resistance are applied IN GENERAL: Blood Flow = Pressure/Resistance • Greater the pressure difference between two points- the greater the blood flow • Greater the resistance- the less blood flow

Answer 31

• Movement of blood through a vessel, tissue, or organ, and is usually expressed in terms of volume of blood per unit of time (ml min) • Amount of blood flowing through an organ, tissue or blood vessel in a given time

Answer 32

• Blood flow through a particular volume or mass of tissue • Commonly expressed in ml per 100 grams of tissue per minute

Answer 33

• Pressure exerted by the blood on the walls of the blood vessels especially the arteries

Answer 34

• Difference between systolic and diastolic blood pressure • Maximum force/stress forced placed on small arteries

Answer 35

• Expansion and recoiling effect of the arteries during systole and diastole • Effect diminishes over distance from the heart

Answer 36

• Average arterial pressure throughout one cardiac cycle • Average force driving blood into vessels that serve the tissues • Influenced by cardiac output and systemic vascular resistance • Maintained around 100 mm Hg (to ensure blood flow) • MAP = Diastolic Pressure + (Pulse Pressure/3)

Answer 37

• Also called Total Systemic Resistance (TSR) • Opposition of blood flow that blood faces in blood vessels • Resistance of the arteries to blood flowing through them • Pressure is affected by resistance • Blood flow is affected by both pressure and resistance

Answer 38

• SYSTOLIC PRESSURE / DIASTOLIC PRESSURE • Systolic Pressure = ventricles contracting • Diastolic Pressure = ventricles relaxing

Answer 39

Relationship between vascular flow, the pressure difference, and resistance • Basic blood flow equation • Q = blood flow rate • ΔP = blood pressure difference • R = resistance to blood flow Flow = pressure difference/ resistance

Answer 40

Q = blood flow rate ΔP = blood pressure difference

Answer 41

C. Blood flow

Answer 42

1. Transport nutrients and waste products 2. Thermoregulation 3. Immune support and Hemostasis 4. Fluid balance within the body • Composed of • Blood Vessels - Arteries, capillaries, veins • Blood - Formed Elements and Plasma

Answer 43

• Tunica Externa (Adventitia) • Loose connective tissue • Adheres vessel to surrounding tissues • Tunica Media • Commonly the thickest • Smooth muscle and collagen fibers • Strengthens the vessel • Regulates diameter of blood vessel • Tunica Interna (Intima) • Endothelium- single layer squamous epithelium and thin basement membrane • Continuous of the endocardium of heart

Answer 44

• Nutrient and waste exchange • Site where nutrients, gases, water, and solutes are exchanged between the blood and the tissues • Lipid-soluble substances (O2 and CO2) - Cross the capillary wall by diffusing through the endothelial plasma membranes • Water-soluble substances (Electrolytes) - Cross the capillary wall through intracellular clefts (spaces) or through large pores in the walls of some capillaries

Answer 45

Arteries • Carry blood away from the heart • 99% of blood transport is oxygenated • Designed to withstand increased pressure • Tunica media has a thick layer of smooth muscle • Have a higher blood pressure

Answer 46

• Always tonically active - Meaning always contracted to some degree • Innervated by the sympathetic nervous system • α1-Adrenergic Receptors: Cause vasoconstriction • β2-Adrenergic Receptors: Cause vasodilation • Only in skeletal muscle • Site of highest resistance in the vasculature • Sympathetic NS • Myogenic • Local Factors • Tremendous influence for blood pressure maintenance and tissue perfusion

Answer 47

• Consist only of endothelium and basal lamina - Single layer of epithelial cells and basement membrane

Answer 48

1. Continuous Capillaries • Most common type in the body content • Have intercellular clefts — Spaces between endothelial cells over again. — Allow smaller molecules to pass through • Some have pericytes — Assist with regulating flow of blood through capillary 2. Fenestrated Capillaries • Have filtration pores scattered throughout them • Allow quick passage of smaller molecules out of capillary but maintain larger ones in • Commonly found in kidneys, endocrine glands, and GI system 3. Sinusoids • Irregular blood-filled spaces in the liver, spleen, and bone marrow • Endothelial cells have wide gaps b/w them • Important to have these large spaces so larger protein molecules can pass through them

Answer 49

Blood is composed of: • Formed Elements (Blood Cells); (45%) • Plasma; (55%) • Formed Elements (cells) • Erythrocytes • Leukocytes • Thrombocytes • Plasma • Water • Plasma Proteins • Solutes

Answer 50

• Erythrocytes (RBCs) • 99% of formed elements • Carry oxygen • Hemoglobin • Heme • Globin • Role of iron • Leukocytes (WBCs) • Immunity function • Thrombocytes • Platelets • Hemostasis process - Clotting

Answer 51

• Leukocytes — Granulocytes • Neutrophil • Eosinophil • Basophil — Agranulocytes • Lymphocytes • Monocytes Lymphocytes: 20% to 40% • Adaptable immune system • Antibody - Antigen reaction Monocytes • Chronic infections • 2% to 8% Eosinophils • Allergies, parasites, inflammation • 1% to 4% Neutrophils: 40% to 60% • Innate immune system • Think of them as first responders • Basophils • Allergic reactions • 0.5% to 1%

Answer 52

Water (92%) • About 92% • It’s water Solutes (1%) • About Dissolved particles and molecules • Electrolytes, glucose, hormones Plasma Proteins (7%) • Albumin • Globulins • Fibrinogen

Answer 53

Albumin (54%) • Most abundant of the plasma proteins • Made by the liver • Helps to transport molecules in blood • Most significant contributor to the osmotic pressure of blood • Its presence holds water inside the blood vessels and draws water from the tissues, across blood vessel walls, and into the bloodstream Globulins (38%) • Alpha, beta, and gamma globulins • Alpha and Beta help transport molecules produced by liver • Gamma globulins are involved in immunity • More commonly known as antibodies Fibrinogen (8%) • Necessary for blood clotting • Made by the liver

Answer 54

Superior and Inferior Vena Cava Right atrium Tricuspid valve (AV valve) Right Ventricle Pulmonary Semilunar valve Pulmonary Trunk Lung Left atrium Bicuspid valve (AV valve) Left Ventricle Aortic Semilunar valve Aorta Body

Answer 55

Right Atrium receives blood from the systemic circuit • Inferior and superior vena cava • Deoxygenated Right Ventricle pumps blood through the Pulmonary Valve into the pulmonary artery • Deoxygenated blood Left Atrium: receives blood from pulmonary circuit • Pulmonary veins • Oxygenated Left Ventricle pumps blood through the Aortic Valve into aorta • Oxygenated

Answer 56

• 1. Viscosity (η) of blood • 2. Vessel length (λ) • 3. Radius (r) of vessel • Opposition of blood flow that blood faces in blood vessels • Resistance of the arteries to blood flowing through them • Pressure is affected by resistance • Blood flow is affected by both pressure and resistance

Answer 57

• 1. Change in pressure • 2. Radius of the vessel • 3. Viscosity of the blood • 4. Length of the vessel

Answer 58

BLOOD VESSEL LENGTH • Length of a vessel is directly proportional to its resistance • The longer the vessel, the greater the resistance and the lower of blood flow • As an adult- fairly consistent • A) Weight Gain/Loss • An individual weighing 150 pounds has approximately 60,000 miles of vessels in the body • Gaining about 10 pounds adds from 2000 to 4000 miles of vessels • Skeletal muscle has more need for vessels than adipose tissue

Answer 59

• Fastest and most significant change to resistance! • A lot of variables that influence vessel radius • VASOMOTOR of the vessel is the contractile state of the smooth muscle • Vasoconstriction • Vasodilation • Vasomotor Center • Located in the Medulla

Answer 60

• Compliance - The ability of a blood vessel to expand and accommodate increased volume of blood - Think metal pipe vs water balloon • As compliance is reduced: resistance to blood flow is increased

Answer 61

C. Arterioles

Answer 62

Sinusoid capillary

Answer 63

Albumin- it increases solute concentration (osmolarity)

Answer 64

Blood vessel radius

Answer 65

Increased viscosity causes increased blood pressure, and decreased blood flow

Answer 66

Changing blood volume, plasma proteins, or erythrocyte volume

Answer 67

Decreased radius causes increased blood pressure, and decreased blood flow

Answer 68

Decreased compliance causes increases blood pressure and decreased blood flow

Answer 69

Hypoxia leads to vasodilation

Answer 70

Baroreceptors detected MAP and adjust blood pressure accordingly

Answer 71

Increases water retention within the kidneys and leads to increased blood volume

Answer 72

Converts angiotensinogen to angiotensin I

Answer 73

• Systolic pressure (mm Hg) / Diastolic pressure (mm Hg) • Normal: 120 mm Hg / 80 mm Hg • Hypertension • Hypotension

Answer 74

• Blood Flow — Blood Vessels — Blood Cells • Resistance of blood flow • Blood Pressure

Answer 75

Systole/Systolic • Pressure in blood vessels when the ventricles are CONTRACTING Diastole/Diastolic • Pressure in blood vessels when the ventricles are NOT CONTRACTING (relaxing)

Answer 76

• Autoregulation refers to the ability of tissues to regulate their own blood flow • Chemical signals work at the level of the precapillary sphincters to trigger either vasoconstriction or vasodilation

Answer 77

1. Baroreceptors • Provides input regarding changes in BP (MAP) • As BP increases, rate of AP increases • Found in the carotid sinus and aorta • Negative feedback loop- part of what concept? • Short-term influence on BP 2. Chemoreceptors • Provide input on changes with primarily pH and CO 2 & O2 • Found in the carotid and aortic bodies • Primary Role • Adjust respiration rate in changes to blood chemistry (pH) • Secondary Role • Vasomotor influences

Answer 78

Aldosterone • Mineralocorticoid steroid hormone produced by adrenal glands TWO MAIN FUNCTIONS • Primarily promotes sodium (Na +) ion reabsorption in kidneys • Leads to secretion of potassium (K+) ions into the urine • Water and sodium ions are dangerous BFFs • Where sodium goes; water does too Antidiuretic Hormone • AKA: ADH and Vasopressin • Produced by the hypothalamus and stored in the posterior pituitary • FUNCTION • Assists in the regulation of plasma osmolarity • Stimulates the collecting duct in the kidneys to reabsorb water Atrial Natriuretic Peptide • Synthesized, stored, and released by atrial myocytes in response to atrial stretch • If there is increased atrial stretch in the myocytes- what does that mean? • FUNCTION • Reduce arterial pressure by decreasing blood volume and systemic peripheral resistance • Primary effect is to stimulate the release of sodium (Na +) from kidneys into urine • Water and sodium ions are BFFs • Where sodium goes; water does too

Answer 79

• Renin-Angiotensin-Aldosterone System Regulation: • 1. Blood volume • 2. Peripheral Resistance • 3. Indirectly influences CO and BP

Answer 80

• Renin is secreted by the kidneys due to: • Renal artery hypotension • Decreased sodium within the distal tubules of the kidney • Renin Function • Converts Angiotensinogen to Angiotensin I

Answer 81

• Angiotensin I is converted to Angiotensin II by Angiotensin Converting Enzyme (ACE) • Angiotensin Converting Enzyme (ACE) • Secreted by endothelial cells primarily in lungs (and kidneys) • Converts Angiotensin I to Angiotensin II

Answer 82

• 1. Stimulate the release of aldosterone • 2. Directly stimulates kidneys to reabsorb sodium (Na +) ions • 3. Increases thirst for increased water intake • 4. Stimulates the release • 5. Stimulates the Sympathetic Nervous System

Answer 83

Increased BP due to increased water in the blood

Answer 84

• As volume decreases- pressure decreases • As volume increases- pressure increases

Answer 85

• Difference of fluid pressure between two locations • Blood moves from an area of HIGH to LOW pressure — Down the pressure gradient

Answer 86

• Refers to the part of cardiac cycle when CONTRACTION IS OCCURING • Can be used to refer to Ventricles and Atria

Answer 87

• Refers to the part of the cardiac cycle when CONTRACTION IS NOT OCCURING • Can be used to refer to Ventricles and Atria

Answer 88

• Amount of blood ejected from each ventricle during ventricular contraction • Default is the left ventricle • SV = EDV - ESV

Answer 89

• The volume of blood in the VENTRICLES right before contraction

Answer 90

• The volume of blood in the VENTRICLES right after contraction

Answer 91

• When the ventricles are CONTRACTING and PRESSURE is INCREASING with NO CHANGES to the volume of blood in ventricles • Remember….pressure in ventricles has to exceed pressure in vessels for blood to move • AV valves close and increasing pressure will open the semilunar valves

Answer 92

• When the ventricles are RELAXING and PRESSURE is DECREASING with NO CHANGES to the volume of blood in ventricles • Semilunar valves close and right before the AV valves start to open

Answer 93

• 1. Atrial Systole • Atrial myocytes contracting • 2. Isovolumetric Ventricular Contraction • Ventricular systole • 3. Rapid Ventricular Ejection • Ventricular systole • 4. Reduced Ventricular Ejection • Ventricular systole • 5. Isovolumetric Ventricular Relaxation • Ventricular diastole • 6. Rapid Ventricular Filling • Ventricular diastole • 7. Reduced Ventricular Filling • Ventricular diastole

Answer 94

• Atria myocytes contract (systole) • Ventricles are in diastole • Blood naturally flows from atrium to ventricle but the the atrium will contract to pump remaining blood into ventricle • AV Valves are open

Answer 95

• Right before ventricles contract: EDV • ISOVOLUMETRIC CONTRACTION • Ventricular myocytes CONTRACT • NO CHANGE in volume of blood in ventricles • So what happens? • AV Valves close • PRODUCES S 1 HEART SOUND: lub • Semilunar Valves are closed too • Step 2: Highlights / Associations • End Diastolic Volume (EDV) • S 1 Heart Sound — AV Valves closing — Lub sound • Myocytes contracting with no change in blood volume in ventricles

Answer 96

• Ventricle continues to contract! • Ventricular pressure becomes greater than semilunar valves • Blood is rapidly pushed out of ventricles into respective vessels • Ventricular volume decreases • Ventricular Systole; Atrium Diastole • Correlates to what portion of ECG?

Answer 97

• End stages of ventricular contraction and start of ventricular repolarization • AV valves still closed but semilunar valves open • Ventricular pressure is decreasing and volume of blood is decreasing still • Ventricles still in systole with increasing atrial pressure

Answer 98

• Beginning of ventricular diastole • Right after ventricles contract: ESV • ISOVOLUMETRIC RELAXATION — Ventricular myocytes are NOT CONTRACTING — NO CHANGE in volume of blood in ventricles • ALL HEART VALVES CLOSED • Once ventricular pressure is below aorta/pulmonary arteries — Semilunar Valves close — PRODUCES S2 HEART SOUND: dub • Step 5 Highlights/Association • Start of ventricular diastole • End Systolic Volume (EDV) • S 2 Heart Sound — Semilunar Valves closing — Dub sound • Myocytes ARE NOT CONTRACTING • NO CHANGE in blood volume • AV and Semilunar valves closed

Answer 99

• When ventricular pressure falls below atrial pressure • Blood rushes from the atria into the ventricles • Pressure in ventricle stays low as blood fills ventricles • Aortic and pulmonary arterial pressure is dropping

Answer 100

• End stage of ventricular diastole • Ventricles still filling up with blood but not as rapidly • Atria start to depolarize

Answer 101

Isovolumetric contraction occurs first • All heart valves are closed and the volume of blood volume stays the same • Ventricles just finished diastole Ventricular contraction causes increase of pressure • Closes the AV valves (S 1 heart sound) • Opens the Semilunar valves End Diastolic Volume (EDV) occurs • Volume of blood in the ventricle right before ventricular systole (contraction) • ~120-130 mL of blood • Only about 30 mL is from atrial systole

Answer 102

Isovolumetric relaxation occurs first • All heart valves are closed and the volume of blood stays the same • Ventricles just finished systole Ventricular relaxation causes decrease of pressure • Closes the Semilunar Valves (S2 heart sound) • Causes AV Valves to open End Systolic Volume (ESV) occurs • Volume of blood in the ventricle right after ventricles finish contraction • Amount of blood remaining in the ventricle after contraction • ~60 mL of blood

Answer 103

Isovolumetric relaxatio

Answer 104

ST segment

Answer 105

Ventricle myocytes are contracting but the semilunar and AV valves are closed- so no change in blood volume

Answer 106

- is the amount of blood pumped from each ventricle in one minute • Varies wildly to meet metabolic demands of the body • Cardiac Output Equation: • Stroke Volume (x) Heart Rate = Cardiac Output • SV x HR = CO

Answer 107

1. Preload • Stretch on the ventricles prior to contraction 2. Contractility • Force or strength of the contraction 3. Afterload • Force the ventricles must generate to pump blood against the resistance in the vessels

Answer 108

• Stretch on the ventricles prior to contraction • Related to the sarcomere length at the end of diastole

Answer 109

• Preload increases • Ventricular muscle is increasingly stretched • Sarcomere length increases

Answer 110

• Important to understand there is an optimal length/stretch placed upon the sarcomeres that will correlate to the optimal force of contraction • Rubberband visual!

Answer 111

• As sarcomeres are stretch, they will contract more forcefully • There is an optimal length of stretch • Going beyond that- strength of contraction decreases

Answer 112

• The greater the contraction force, the greater the stroke volume • Intrinsically: Frank Starling Mechanism • Extrinsically: Positive and Negative Inotropic Agents

Answer 113

• 1. Sympathetic Nervous System • 2nd Messenger system • 2. Drugs/actions that increase Calcium (Ca 2+) ion concentration • Cardiac glycosides • Digitalis • Inactivation of Sodium/Potassium ATPase pump • Keeps Calcium (Ca 2+) ions within the cell

Answer 114

• Parasympathetic Nervous System • Beta Blockers • Calcium Channel Blockers • Hypoxia, hypercapnia (increased CO2), acidosis • Lead to a negative inotropic effect

Answer 115

• Force the ventricles must overcome to pump blood into the vessels • The resistance in the vessels • Variables can make it easier or more difficult to pump blood out to body’s circuit • Increasing Afterload • HYPERTENSION!!!!!!!!!!! • Atherosclerosis • Vasoconstriction • Decreasing Afterload • Vasodilation

Answer 116

• Resistance of blood flow through all of the body’s vessels except pulmonary circuit

Answer 117

• Resistance of blood flow through only the pulmonary circuit

Answer 118

• Tachycardia: above 100 bpm • Bradycardia: below 60 bpm

Answer 119

• Sympathetic NS – Catecholamines • Increased metabolic needs of the body • Hyperthyroidism • Caffeine/Nicotine • Elevated body temperature

Answer 120

• Parasympathetic NS • Hypothyroidism • Decreased body temperature

Answer 121

• Measurement (in percentage) of how much blood is pumped out with each contraction in the left ventricle • It is a measurement of how well (healthy) the heart is • Ejection Fraction = Stroke Volume / End Diastolic Volume • EF = SV / EDV • Ejection Fraction Should Be: • Normal: 50-70% • High: >70% • Low: <50%

Answer 122

Frank Starling Law

Answer 123

Decreased CO by increasing peripheral resistance and increasing ESV

Module 1: Cardiac Muscle And Hemodynamics Flashcards

(167 cards)