Cardiac Anatomy Lecture Powerpoint Flashcards
fuck me
Ductus arteriosus becomes what at birth?
Ligamentum arteriosum
In fetal circulation there is blood shunting from…
Upon birth this changes to…
….right to left because right is higher pressure than left in fetal circulation
….left sided pressure higher than right due to the inflation of the lungs dropping pressure
Atrial septal defect (primum and secundum)
Occurs when there is an incomplete closure of the septum wall, primum occurs much lower in the heart wall close to the ventricle while secundum occurs higher closer to the base of the heart
Borders of the mediastinum
thoracic inlet superiorally diaphragm inferiorally sternum anteriorally spine posteriorally pleura laterally left and right
The entire posterior face of the heart is the ____ and ___
The entire anterior surface of the heart is the____
The entire right side of the heart is the ____
The entire left side of the heart is the ___
left ventricle, left atrium, right ventricle, Right atrium, left ventricle
Where is the AV node located in the heart?
In the intraventricular septum
How many pumonary veins are there?
4
How many pulmonary arteries are there
2
Right coronary artery pathway and what does it supply
Right coronary artery travels in the groove between the right atrium and right ventricle supplying both of them
Left coronary artery pathway and what does it supply
divides into LAD and circumflex artery, LAD goes between right ventricle and left ventricle (majority of supply for the left) circumflex goes between groove between left atrium and ventricle around on the posterior side supplying the left atrium
Marginal branch vs diagonal branch
Marginal branch comes off the right coronary artery while the diagonal are branches coming off LAD
Coronary sinus
Main venous blood return from the entire heart,
The arterial vasculature has much ___ smooth muscle layer than the venous side
thicker
Vasovasorum
Blood supply to the vessels that travels thru the tunica externa of large vessels in the body
3 Great vessels off aortic arch
Brachiocephalic trunk, left common carotid, left subclavian
3 vessels that come off anterior side of aorta and are not paired and what they supply
- celiac trunk (stomach liver spleen pancreas duodenum
- superior mesenteric (all of jejunum, ileum, most of ascending and part of transverse colon)
- inferior mesenteric (remainder of transverse colon and descending colon)
Blood flow (perfusion) factors
- viscosity (hematocrit)
- cardiac
- local factors
- humoral
- intraluminal factors
Fahraeus-lindqvist effect
Idea that viscosity of blood changes inversely with the diameter of the tube it travels thru. In small vessels, the viscosity is lower.
Intravascular pressure from aorta to vena cava
Aorta to small arteries is very high,
arterioles see a drop,
capillaries thru vena cava see continuous drop
Central venous pressure (CVP)
Pressure in the venous system typically measured as close to the heart as possible, tends to be very similar thru the entire venous system
Pulmonary artery capillary wedge pressure (PACWP)
An indirect measure of left atrial pressure that can estimate intravascular volume obtained by using a catheter that travels into the right atrium to right ventricle then to pulmonary vasculature until it is eventually obstructed at a small vessel, with the pressure sensor in it measuring everything downstream and therefore left atrial pressure
Mean arterial pressure=
cardiac output x systemic vascular resistance
Cardiac output=
Stroke volume x heart rate
Stroke volume=
LV end diastolic volume x contractilty
Atrial kick adds ___% to EDV
20
The fetus lacks ___ circulation
Pulmonary
2 pathways the fetal heart shunts blood from the right side of the body to the left side while avoiding the pulmonary circulation
- foramen ovale between right to left atrium
- ductus arteriosus between pulmonary trunk and aortic arch
Shear force is most likely to cause a tear in the aorta at this point
The ligamentum arteriosum
Where is the SA node located in the right atrium?
At the junction between superior vena cava and right atrium posterior wall
The aorta loops….
…anteriorally in front of the right pulmonary artery then travels posterior to the heart and left pulmonary artery (where the ligamentum arteriosum sits) in front of the spine to descend as the thoracic aorta
The aortic valve has ___ leaflets
The right and left leaflets have the….
3, openings to the left and right main coronary arteries
___% of blood supply to the heart returns to chambers via the myocardium itself
10-20
Coronary sinus
Valveless main venous blood return from the entire heart surface, oriface is located at the lower portion of the right atrium just medial to where the vena cava enters
Cardiac index
Cardiac output/body surface area, preferred measure than cardiac output for determining adequate blood flow from heart
During diastole, mitral and tricuspid valves are ___ and aortic and pulmonic valves are ____
open, closed
Atrial kick
Refers to atrial contraction that occurs prior to end of diastole that pushes an extra bolus of blood from atria to ventricles to fill them
Isovolumetric contraction
Refers to short period where ventricular pressure rises above atrium that results in mitral and tricuspid valves shutting to prevent backflow (S1), but before the pressure has built enough to exceed the resistance of the aortic and pulmonic valves in which they open
When aortic pressure exceeds ventricular pressure in systole, what happens?
The aortic valve closes (S2)
Isometric relaxation
Refers to short period where ventricle relaxes and sees a drop in pressure after ejecting blood into the aorta/pulmonary trunk, but before pressure has dropped below atrial pressure to allow mitral/tricuspid valves to open and begin filling again
Dicrotic notch
Small downward deflection observed in pressure readings of the ventricle where the aortic valve slams shut indicating end of systole and start of diastole
Compliance =
increase in volume/increase in pressure, 24x greater in venous side than arterial, venous acts as a reserve for intravascular volume
Preload
The weight of the volume being ejected from the heart that must be overcome to perfuse blood (intravascular volume)
Afterload
The weight of the volume of blood in circulation that the heart must eject against in order to overcome and perfuse blood (The peripheral vascular resistance)
In order to pump blood, the ventricle must overcome both ___ and ____
preload, afterload
Local regulation of blood flow 2 theories
- vasodilator theory: metabolite buildup stimulate local dilation of precapillary tubules
- oxygen demand theory: low O2 stimulates local dilation of precapillary tubules
Intra-aortic balloon pump
Sits above renal vessels and below great vessels and inflates and deflates with saline corresponding to ekg allowing for decrease of peripheral resistance but maximize blood flow to coronary vessels that are still open so the heart is not damaged.
