Cardiac A &P Flashcards
(104 cards)
What does the left circumflex perfuse?
Supplies the left atrial wall, the posterior & lateral LV, anterolateral papillary muscle, the AV node in 10% of the population, and the SA node in 40-45% of the population.
What does the right coronary artery perfuse?
Supplies blood to the SA and AV nodes, the RA and RV, the posterior third of the interventricular septum, the posterior fascicle of the left bundle branch, and the interatrial septum.
Describe the position of the Heart within the sternum
- Bounded anteriorly by the sternum and costal cartilages.
- Positioned between Ribs 3, 4, and 5
- Superior to diaphragm
- Apex of the heart projects anteriorly
Normal volume of serous fluid in the pericardium. What is the function of this fluid?
10-25mL serous fluid
provides lubrication and free movement
From external to internal, what are the layers of pericardium?
Fibrous pericardium, parietal pericardium, and visceral pericardium
What chamber of the heart has the thinnest layer? Making is the easiest to lacerate during cardiac surgery.
Right Atrium ~2mm thick
The right atrium receives blood from?
IVC, SVC, and Coronary Sinus
The coronary sinus receives blood from the coronary veins, making it a useful cannulation location for cardioplegia for cardiac bypass. Is this retrograde or anterograde cardioplegia?
Retrograde. Send solution backward through coronary veins.
The coronary sinus is also used to place what kind of pacemaker?
Bi Ventricular Pacemaker. The third lead is threaded through the sinus down a vein that travels along the LV and then sits right outside the LV.
Atrial kick produces what percent of Left Ventricular End Diastolic Volume (LVEDV) in patients with a normal mitral valve
20%
When a patient has mitral stenosis, the atrial kick can be reduced up to what %?
40%!
Atrial kick provides up to 40% of LVEDV
What is the most common cause of RV failure?
LV Failure
RV wall thickness is how much thicker than RA wall thickness?
2x
~4-5mm thick
The left atrium receives oxygenated blood from the ____ pulmonary veins
FOUR
Do both atria contract or only one?
Both RA and LA contract during atrial systole
How thick is the LV wall?
~8-15mm. Needs to be the thickest to overcome SVR
What helps prevent the atrioventricular valves (TV and MV) from everting back into atria?
papillary muscles with chordae tendineae
The LAD primarily supplies blood to which parts of the heart?
Anterior 2/3 of interventricular septum
RBB and LBB
MV Papillary Muscles
and Anterior Lateral / Apical LV Walls
It also provides collateral circulation to the Anterior Wall of the RV.
What is the significance of the Sinus of Valsalva?
Small dilation above the aortic valve that allows the AV to open without occluding the (coronary ostia) openings of the coronary arteries.
Heart valves open and close due to?
changes in pressure gradients
Blood moves from an area of high pressure to lower pressure
Semilunar Valves (PV and AV) are composed of ____ cusps.
3
(bicuspid AV bad)
The left circumflex artery supplies blood to?
The posterior and lateral LV walls
Left atrial Wall
SA node in 40-45% population
AV node in 10% population
The right coronary artery (RCA) supplies blood to?
The SA and AV nodes
Posterior 1/3 of interventricular spetum
SA node - 50-60% population
AV node- 90% population
What is coronary artery dominance?
Pertains to what artery provides blood to the posterior descending artery (PDA).
50% of the population is via RCA
The other is sometimes LCA or LCx