Cardiac Anatomy Flashcards
Top part of the heart is called?
Base
What are the 4 properties of the cardiac conductive system?
Excitability
Conductivity
Automaticity
Contractility
How does the cardiac conductive system work?
Via sodium-potassium pump
Polarization is?
Resting potential
Depolarization is?
Action potential
K+
Potassium
Where is the potassium located after the depolarization phase?
Outside of cell
Where is sodium located after the depolarization phase?
Inside of cell
What is the name for the bottom portion of the heart?
Apex
Where is potassium located during the polarization phase?
Inside of cell
Where is the sodium located in the polarization phase?
Outside of cell
Which valve of the heart is more likely to become inverted?
Bicuspid/Mitral valve
Is the blood in the right side of the heart oxygenated or deoxygenated?
Deoxygenated
What is the only artery that contains deoxygenated blood?
Pulmonary Artery
Which muscles are attached to the heart valves and help to prevent valves from inverting?
Papillary
What is ANH?
Atrial natriuretic hormone which is provided by the stretching of the walls
What is the main functions of Atrial Natriuretic Hormone?
Decreases reabsorption of sodium ions in the kidneys
Promotes increase in sodium elimination thru urine
BLOOD VOLUME LOWERS WHICH LOWERS BLOOD PRESSURE
What part of the heart is thicker walled and is capable of more forceful contractions?
Left ventricle
Quivering of artia is what?
Atrial fibrillation
Coronary vessels originate where?
Ascending aorta
Epinephrine is given in cardiac arrest because?
EPI vasoconstricts peripheral vessels which forces more blood into coronary vessels first
What are the three “i’s” associated with occluded coronary vessels?
Ischemia
Injury
Infacrt
Ischemia occurs when?
More demand for oxygen then supply
LEAST HARMFUL
Injury on a 12 lead appears how?
ST elevation
What is the worst rhythm seen with extreme coronary vessel obstruction?
Infarct
Contraction of the ventricles of the heart is known as?
Systole
Relaxation of the heart is known as?
Diastole
What is systolic pressure?
Strength and volume of cardiac output
What can decrease stroke volume?
Decrease in preload
What does heart rate do when in hypovolemia?
Increases
Mean arterial pressure less than 60 indicates?
Lack of perfusion to brain
What heart sound indicates a heart murmur?
Third heart sound
Mitral valve stenosis occurs when?
The valve becomes ridged and cannot open or close easily
What is the intrinsic rate of the SA node?
60-100
What is the step of the cardiac electrical system between the SA node and the AV node?
Internodal arterial pathways
Normal intrinsic rate for AV node?
40-60
What is the intrinsic rate for the purkinje fibers?
20-40
Natural pacemaker of the heart
SA node
What part of the cardiac electric system creates a”delay” before current is sent to perkinje fibers?
AV node
The right bundle branch supplies an impulse to what part of the heart?
Right ventricle
What parts of the heart does the left bundle branch supply electrical impulses to?
Left anterior ventricle and left posterior ventricle
What is a normal heart rate for an infant?
120
What is the normal heart rate for a child?
100BPM
What contains the accelerator and inhibitory center?
Medulla
Chronotropy is?
Heart Rate
Positive chronotropic effect is?
Increases heart rate
Inotrophy is?
Contractile force
Dromotropy is?
Electrical conduction of heart
____ and ____ describe mechanical functions of heart.
Chronotropy and inotopy
What does the parasympathetic system decrease?
Heart rate, strength of contractions, blood pressure
The parasympathetic nervous system increases?
Digestive system and kidneys
The sympathetic system increases?
Body activity, heart rate, strength of contractions, vascular constriction, respirations, bronchodilation
PUPILS DILATE
SKELETAL MUSCLE PERFUSION INCREASES
The sympathetic system decreases?
Urine output
What are the main catecholamines?
EPI and Norepi
Alpha 1 is?
Vasoconstriction, Increased peripheral vascular resistance, Increased preload
Alpha 2 is?
Regulation of the release of NorEpi
Beta 1 is?
Positive inotropy, positive chronotropy, positive dromotropy
Beta 2 is?
Bronchodilation, smooth muscle dilation in bowel
Only time epi is given for bradycardia?
With children to increase heart rate
Atropine is given for?
Symptomatic bradycardia; Atropine works on the atria only
Transcutaneous pacing works on what part of the heart?
Ventricles only
Dopamine works on atria or ventricles?
Ventricles
Blood oxygen levels are regulated by what type of receptors? Where are they located?
Chemoreceptors found in carotid and aortic bodies
Blood pressure levels are regulated by what type of receptors? Where are they located?
Pressoreceptors found in carotid and aortic sinuses
The inhibitory center sends impulses along the vagus nerves found where?
10th cranial
Glassopharengeal nerves are stimulated by which set of nerves?
9th cranial nerves
What is ejection fraction?
Ratio of blood pumped from the ventricle to the amount remaining at the end of diastole
What is the average stroke volume amount?
70mL
Stroke volume depends on what three factors?
Preload, cardiac Contractility, and afterload
What is preload?
The end-diastolic volume
Define starlings law?
The more the myocardium is stretched, the greater the force of contraction
How is stroke volume affected by peripheral resistance?
Inverse relationship. An increase in peripheral resistance will decrease stroke volume and vice versa
What is the average cardiac output?
5 liters
During stress which system dominates?
Sympathetic (raises heart rate and increases contractile force)
During sleep, which system dominates?
Parasympathetic; decreases heart rate and contractile force
Which electrolyte depolarizes heart cell?
Sodium
The hearts pumping ability is evaluated using?
Pulse and blood pressure
Which side of the heart is the systemic loop?
Left
Which side of the heart is the pulmonic loop?
Right
What is the purpose of the atrias?
Act as a reservoir to fill ventricles
Where are atrioventricular valves found?
Between atrium and ventricles
Which side of the heart is the workhorse?
Left
Stroke volume x HR = ?
Cardiac output
How is preload affected?
Contractility is increased (example: digoxin) and blood vessels are dilated
Decreasing vascular resistance ____ preload.
Increases
Vasoconstriction _____ preload.
Decreases