The Heart Exam Flashcards
Which circuit is on the right side?
Pulmonary circuit
What does the Pulmonary circuit do?
Carries blood to the lungs to be oxygenated and back to the heart
Which circuit is on the left side?
Systemic circuit
What does the Systemic circuit do?
Carries oxygenated blood to the tissues and returns to the heart
What part of the heart sends all the organs blood?
The aorta
What brings oxygenated blood from the lungs?
Pulmonary veins
How does deoxygenated blood go to the heart?
The inferior and superior venae cavae
What sends blood to the lungs?
The pulmonary trunk
Where is the base of the heart?
The top larger part
Where is the apex of the heart?
The small end
What covers the heart?
Pericardium
What is the deepest layer of the heart?
The endocardium
What is the middle “meaty” layer of the heart?
The myocardium
What is the outermost layer of the heart?
The epicardium
The little gap in the layer of pericardium is called?
The pericardial cavity
The pericardial cavity has two layers, what are they?
The fibrous layer and the serous layer
What’s the purpose of the pericardium?
Allows heart to beat without friction and room for expansion
What is the other name for epicardium?
The visceral pericardium
What is the parietal pericardium?
The pericardial sac
What is the inflammation of the pericardium membrane called?
Pericarditis
What is another term for the myocardium?
The fibrous skeleton of the heart
What are the four chambers of the heart?
Left and right atria, left and right ventricles
Which chambers are inferior?
the ventricles
What does the pulmonary trunk do?
Main blood vessels for the right side going to the lungs (deoxygenated)
What chamber does the superior and inferior vena cava go to?
The right atria
What does systole mean?
contraction
What does diastole mean?
relaxed
What separates the atria?
The interatrial septum
What is the internal ridges of myocardium called?
Pectinate muscles
What separates the ventricles?
The interventricular septum
What are the ridges in the ventricles called?
Trabeculae carneae
What are the 3 and 2 muscles called in the ventricles?
Papillary muscles
What separates the atria and ventricles?
Atrioventricular sulcus
What overlays the interventricular septum?
The interventricular sulcus
What are the two valves?
The Atrioventricular and Semilunar
What do the valves do?
Ensure one-way flow of blood through heart
What does the atrioventricular valve control blood flow between?
The atria and ventricles
What is the right AV valve?
The tricuspid valve
What is the left AV valve?
The mitral valve
What are the cords connective the AV valves to the papillary muscle?
The chordae tendineae
What does the semilunar valve control flow of?
Control flow into great arteries
Where is the pulmonary semilunar valve?
Between right ventricle and pulmonary trunk
Where is the aortic semilunar valve?
Between left ventricle and aorta
What valve is open when the ventricles relax? (Pressures drops inside the venticles?
The AV valve opens
What valve is open when the ventricles contract?
The Semilunar valve opens
How does the blood enter the heart at first?
In the right atrium from superior and inferior venae cavae
Where does the blood go after the right atrium?
Through the right AV valve into the right ventricle
What causes the pulmonary valve to open?
Contraction of the right ventricle
Where does the blood go after the pulmonary trunk?
It gets oxygenated then returns through pulmonary veins in left atrium
Why is some of the blood pumped by the heart stay in the heart?
Because it goes through strenuous workload and needs oxygen and nutrients
What is the big blue vein on the back of the heart?
The coronary sinus
The aorta has two red veins go down the front, what are they called?
The Right coronary artery and the left coronary artery
What compresses the coronary arteries and obstructs blood flow?
Contraction of the myocardium
What does the opening of the aortic vale during ventricular systole do to coronary arteries?
It blocks blood flow to the coronary arteries
What is the left coronary artery branch called?
The anterior interventricular branch
What is the circumflex branch?
A branch off the LCA
What is the right coronary artery branch called?
The right marginal branch and posterior interventricular branch
What is coronary artery disease?
A constriction of the coronary arteries
What does the coronary artery disease do to blood flow?
There is build-up of fat in the arteries that constricts blood flow
What is Myocardial infarction?
A heart attack
What is angina pectoris?
Chest pain from obstruction of coronary blood flow
When is venous drainage?
5% to 10% coronary blood drains directly into the heart chambers
What does the great cardiac vein do?
Collects blood from anterior portion of heart and empties into coronary sinus
What does the middle cardiac vein do?
Also known as posterior interventricular, collects blood from posterior portion of the heart and drains into coronary sinus
What does the left marginal vein do?
Empties into the coronary sinus
What three veins empty blood into the coronary sinus?
The great cardiac vein, the middle cardiac vein (posterior interventricular), and the left marginal vein
Where does the coronary sinus empty blood
Into the right atrium
What are glycogen?
Sugar storage to help with making atp
What are cardiocytes?
Striated, thick cells with one central nucleus and glycogen
What repairs damage to cardiac muscle?
Fibrosis
What holds cardiocytes together?
Intercalated disc and gap junctions
What are cardiac muscles rich in?
Myoglobin and glycogen
What fill up 25% of the cardiac muscle cells?
Huge mitochondria
What are the cardiac muscle cells most vulnerable to?
Oxygen deficiency
What makes the cardiac muscle cells different from other muscles?
Fatigue resistant
What is known as the internal pacemaker
The Sinotrial node (SA)
What is the first step of the conduction system?
The SA node fires
What does the SA node firing do?
Excitation spreads through atrial myocardium
What happens after the SA node fires?
The AV node fires
What spreads the AV node excitation?
The Purkinje fibers
What do the sympathetic nerves do to the heart rate?
Increases
What do the parasympathetic nerves do to the heart rate?
Decreases
What is the other name for the parasympathetic nerve?
The vagus nerve
What region fires if the SA node is damaged?
The Ectopic focus
What region fires if the SA node and the ectopic focus are damaged?
The nodal rhythm which is set by the AV node
True or false: The SA node has a stable resting membrane potential?
False
What does the SA node start at?
-60 mV
What is pacemaker potential?
Gradual depolarization
What causes the -60 mV to drift upwards?
Slow Na inflow
What happens when it reaches a threshold of -40 mV?
Voltage-gated fast Ca and Na channels open
What happens at 0 mV?
K channels open to let K out of the cell
What causes repolarizaiton?
The K channels opening
When does the pacemaker potential start over?
When K channels close
What does the SA node fire do?
Sets off heartbeat
How much Na goes out and K go in?
3Na outside and 2K inside
What are the steps of the electrical behavior of the myocardium?
- Na gates open
- Rapid depolarization
- Na gates close
- Slow Ca channels open
- Ca channels close and K channels open (Repolarization)
What is the electrocardiogram?
Composite of all action potentials of nodal and myocardial cell detected
What is the P wave?
When the SA node fires and atria depolarize
What is the QRS complex?
Ventricular depolarization
What is the ST segment?
Ventricular systole
What is the T wave?
Ventricular repolarization and relaxation
What is heart block?
Failure to conduction system to conduct
What is premature ventricular contraction?
Extra beats due to the ectopic focus
What is valvular insufficiency?
Any failure of a valve to prevent reflux
What is mitral valve prolapse?
When one or both mitral valve cusps bulge into atria during ventricular contraction.
What is mitral valve prolapse caused by?
Hereditary
What is S1 sound “lubb” caused by?
AV valves closing
What is S2 sound “dupp” caused by?
Semilunar valves closing
What is ventricular filling?
When the ventricles expand and their pressures drops below the atria
What valve opens during ventricular filling?
The AV valve
What is the end-diastolic volume during ventricular filling?
130 mL of blood
What does the atria do during ventricular filling?
they contract
What does the atria do during isovolumetric contraction?
They relax
What valves are open during isovolumetric contraction?
Neither
When sound is during isovolumetric contraction?
S1
How much blood is changed during isovolumetric contraction?
Zero
When does ventricular ejection begin?
When ventricular pressure exceeds arterial pressure and semilunar valves open?
What is the stroke volume during Ventricular ejection?
70 mL
How do you find ESV?
ESV = EDV - SV
When do semilunar valves close?
During isovolumetric relaxation
What sound is heard during isovolumetric relaxation?
S2
What does EDV stand for?
The end- diastolic volume
Was does ESV stand for?
The end- systolic volume
What is Congestive Heart failure?
Failure of either ventricle to eject blood effectively
What does left ventricular failure cause?
Blood goes into the lungs causing pulmonary edema
What does right ventricular failure cause?
Blood backs up into the vena cava causing systemic or generalized edema
What is CO formula?
CO = heart rate x stroke volume
What is the cardiac output normally?
4 to 6 L/min
What is cardiac reserve?
The difference between someone’s maximum and resting CO
What is tachycardia?
Resting adult heart rate above 100 bpm
What is bradycardia?
Resting adult heart rate less than 60 bpm
What are positive chronotropic agents?
Factors that raise heart rate
What are negative chronotropic agents?
Factors that lower heart rate
What is vagal tone?
Holds down the heart rate to 70-80 bpm
What area regulates heart rate?
The medulla oblongata
What does the vagus nerve do to the heart rate?
It decreases it
What does cutting the vagus nerve do to the heart rate?
It increases it
What are the baroreceptors
They are pressure sensors in aorta
Where are baroreceptors located?
In the internal carotid
What three variables govern stroke volume?
Preload, contractility, and afterload
What does increased preload do?
Increase stroke volume
What does increase contractility do?
Increase stroke volume
What does increase afterload do?
Decrease stroke volume
What is preload?
The amount of tension in ventricular myocardium before it contracts
What is the Frank-starling law?
That stroke volume is proportional to the end-diastolic volume
What does hypercalcemia do to contractions?
It causes stronger prolonged contractions
What does hypocalcemia do to contractions?
It causes weak and irregular heartbeat
What is afterload?
Sum of all forces opposing ejection of blood from ventricle
What valve does the afterload oppose to the opening of?
The semilunar valves
What is Cor pulmonale?
Right ventricular failure due to obstructed pulmonary circulation
What does increased muscular activity cause?
Increases preload and cardiac output which increases the stroke volume