lecture-2-heart-and-great-vessels Flashcards
diastole
relaxing of the heart
filling of ventricles
pulmonary and aortic valves (through which blood leaves ventricles) are CLOSED
systole
Contraction of the ventricles
Tricuspid and Bicuspid Valves are closed
the most anterior part of the heart is the
right ventricle
important because of stab wounds
the most posterior portion of the heart
left atrium
important. consider swallowing fish bone
transverse pericardial sinus:
location
clinical importance
posterior to the aorta and pulmonary trunk
anterior to the SVC
surgeons place surgical clamp here so that blood flow cna be diverted during surgery
pericardium
double wall membrane
encloses heart & great vessels
consists of fibrous pericardium and serous pericardium
fibrous pericardium
tough external fibrous layer
serous pericardium
deep to the fibrous pericardium
serous pericardium is ALSO DOUBLE LAYERED - parietal and visceral layers
layers lubricate heart by secreting fluid
layer next to fibrous pericardium is parietal layer
layer surrounding the heart is the visceral layer
pericardial cavity
between parietal and visceral layers of serous pericardium
fluid can accumulate here and lead to constriction of the heart
cardiac tamponade
compression of heart due to excess fluid, pus, blood in pericardial cavity
causes decrease in diastolic filling of the ventricles ==> decrease in stroke volume ==> shock and death
treatment is pericardiocentesis
pericardiocentesis
treatment for cardiac tamponade
procedure: needle used to remove fluid from pericardial sac
common region of drainage is xiphoid and coastal margin
cardiac notch (left lung) allows access to pericardial sac for drainage (5th and 6th ICS)
coronary sinus drains into the
right atrium
only structure that contains pectinate
right atrium
some of the others contain something similar called tubercle carneae
crista terminalis
used to find SA node
fossa ovale
located between left and right atrium
atrial septal defects (ASDs)
occur when foramen ovale is not properly closed during devleopment
15-25% of people have small foramen ovale left (no clinical significance)
large ASDs - significant oxygenated blood from left atrium is shunted to the right atrium
Paradoxal embolism - travels to the brain
structures before birth that impact circulation
Foramen Ovale
bypass lungs
RA => foramen ovale => LA
Ductus Arteriosus
bypass lungs
RV => ductus arteriosus => aorta => body
BOTH bypass lungs
chorae tendineae
“heartstrings”
connect papillary muscles to the Tricuspid and Mitral (aka Bicuspid) valves
papillary muslces contract during
systole
contraction of papillary muscles ==> tightening of chorea tendineae
moderator band:
location
how you can distinguish it
Right ventricle
in the area of papillary muscles but is not connected to chorea tendineae
considered part the electrical conduction system of the heart
mitral valve has ___ cusps and they are ____-
mitral valve has _TWO__ cusps and they are _ANTERIOR and POSTERIOR___-
aortic valve has ___ number of cusps and they are ______
aortic valve has _THREE__ number of cusps and they are __LEFT, RIGHT, POSTERIOR____
Aortic valve
left cusp
right cusp
LCA
RCA
where is the sinus of valsava
aorta
which CA supplies the SA node?
RCA (via the sinoatrial nodal branch)
in 40% of people the sinoatrial nodal branch comes off the LCA
RCA branch
marginal branch
LCA branch(es)
left circumflex artery
left anterior descending branch (LAD)
dominance refers to where the _________ comes from (RCA or LCA)
dominance refers to where the ____posterior interventicular artery ____ comes from (RCA or LCA)
CA dominance
70% - right
20% - balanced
10% - left
cardiac skeleton functions
attachment for heart muscles
attachment for the valves
prevents over distension
INSULATOR - momentarily halts SA node signal ==> allows atria to contract first
pacemaker-defibrillator
used for patients with irregular heartbeats due to SA AV or conduction system damage.
single lead in RA - stimulates SA node. used when conduction system is NOT damage
double lead in RV - stimulates conducting fibers at the apex. required when AV bundles have been damaged.
APT M 25
“Apartment M 25”
APT M 25 - Aortic Valve; Right 2nd ICS
APT M 25 - Pulmonic Valve; Left 2nd ICS
APT M 25 - Tricuspid Valve; Left 4-5th ICS
APT M 25 - Mitral Valve; Apex of the Heart at 5th ICS
