Heart Flashcards
Systole
When the heart muscle contracts, ventricular contraction
Aortic and pulm valves open
Systolic pressure
Pressure in arteries when the heart contracts
Diastole
When the heart muscle relaxes, ventricular relaxation
Tricuspid and mitral valve open
Diastolic pressure
Pressure in arteries when the heart rests
End diastolic volume
Volume of blood in LV at the end of diastole (right before it contracts)
End systolic volume
Volume of blood in the LV at the end of systole (ventricular ejection)
Stroke volume
Volume of blood pumped out of the LV during systole (SV=EDV-ESV)
Ejection fraction
% of blood the LV pumps out with each contraction (EF=SV/EDVx100)
Cardiac output
Volume of blood pumped/minute (CO=SVxHR)
Preload
Initial stretching of cardiomyocytes prior to contraction (EDV or pressure)
Afterload
Load heart must eject blood against, related to aortic pressure, ventricular wall stress
Isovolumetric relaxation
Ventricular diastole begins
Ventricles relax but volume of blood does not change because all heart valves are closed and pressure in V is still higher than A
Atrial contraction
End of ventricular diastole, atrial systole
Atria contract to force last of blood into the ventricles
Ventricular filling
Ventricular diastole continues
Pressure in A greater than V so AV valves open and blood flows passively
Isovolumetric contraction
Ventricular systole begins and ventricles contract
V pressure is greater than A so AV valves are closed
Pressure not greater than aorta or pulmonary trunk
Ventricular ejection
Ventricular systole continues
Ventricular contraction continues, pressure is now greater than aorta and pulmonary trunk forcing valves open
P-wave
Atrial depolarization that precedes atrial contraction
QRS complex
Ventricular depolarization right before ventricular contraction
T-wave
Repolarization after ventricular contraction
Covering of the heart
Pericardial sac
Pericardial fluid
Lubricates the heart
Tissues of the parietal pericardium
Fibrous layer and serous layer
Fibrous layer
Dense, connective, collagenous tissue
Prevents overfilling
Serous layer
Makes serous fluid
Fibrous layer location
Outer part of the pericardial sac
Serous layer
Balloon that wraps around the heart, creates two layers
Visceral pericardium
Part of the serous layer, closest part to the heart
Pericardial space
Fluid filled space in serous layers
Chamber of the heart that touches the sternum (anterior)
Right ventricle
Chamber of the heart that touches the esophagus (posterior)
Left atrium
Chamber of the heart that forms the base and touches diaphragm and ribs
Left ventricle
Chamber of the heart that forms the right side of heart
Right atrium
Chordae tenineae
Heart strings that are attached to atrioventricular valves that prevent regurgitation
Papillary muscles
Branching heart muscles that attach to chordae tendineae
S1 sound
Lub
Closing of atrioventricular valves during ventricular systole
S2 sound
Dub
Closing of semilunar valves
Diastole
Right coronary artery
Supplies right side of the heart and starts at right cusp of aortic valve
What the right coronary artery supplies
SA nodal artery
Right (acute) marginal artery
Posterior descending (interventricular) artery
Posterior descending (intraventricular) artery
Supplies posterior IV septum
Left coronary artery
Supplies left side of the heart in the coronary sulcus, branches from left cusp of aortic valve
Left coronary artery branches
Left anterior descending artery
Left circumflex artery
Left anterior descending artery
Supplies anterior IV septum and apex
Left circumflex artery
Supplies the left lateral wall
Coronary dominance
When looking at someone’s heart, where the PDA comes from
58% from RCA
20% from LCA
2% from both R and LCA
Cardiac veins
Coronary sinus
Great cardiac vein
Middle cardiac vein
Small cardiac vein
Coronary sinus
Responsible for draining the deoxygenated blood from the heart into the right atrium
Great cardiac vein function and location
Drains the anterior surface of the LV
Overlays the LAD and drains area that that supplies
Middle cardiac vein
Drains posterior walls and posterior IVS
Overlays the PDA
Small cardiac vein
Drains the posterior section of the heart
Where sympathetic innervation of the heart originates
T1-T5 in the spinal cord
Travel of a sympathetic nerve from spinal cord to the heart
Synapses in the lateral horn, travels out the ventral root into the sympathetic chain where it synapses again
Can travel up or down the symp. trunk to cervical or another T, then travels to the heart and synapses again
Location of parasympathetic innervation of the heart
Brainstem (medulla)
Travel of parasympathetic nerve to the heart
Synapses in the medulla and then travels directly to the heart and synapses again
SA Node
Originates in the RA and starts the depolarization of the heart
60-100bpm
AV node
In between the atrium and ventricles
Slows down signal so atrium fully contract before ventricles contract
40-60bpm
Bundle of his
Receives signal from AV node and rapidly sends down the IV septum into left and right bundle branches
Perkinje fibers
Located by the apex of the heart and wraps around and back up the heart so that the ventricles contract
Reaches papillary muscles first so the valves close before contraction
Systolic murmur
Occur during ventricular contraction
Most common murmurs
Valve stenosis and valve insufficiency
Diastolic murmur
Occur during atrial contraction
Stenosis
Failure of a valve to open completely, impedes forward flow by forcing blood through a smaller opening and the flow becomes turbulent
Insufficiency
Also known as regurgitation
Failure of a valve to close completely allowing reversed flow
Murmur occurs when valve should be shut
Why is the anatomical position important
Need a universal view of the body
What is the anatomical position
Patient facing forward, arms at the side, palms front, thumbs to the side, and pt POV (their left arm)
Anterior
Front
Ventral
Front
Posterior
Back
Dorsal
Back
Superior
Above, towards the top
Inferior
Below, towards the bottom
Cranial
Towards the top
Caudal
Towards the bottom