1-Anatomy of the Heart Flashcards
what is the hilum of lung and what is it made up of?
root of lung, made up of:
- pulmonary artery
- main bronchus
- pulmonary veins
- pulmonary lymphatic vessels & bronchopulmonary lymph nodes
- pulmonary visceral afferents & autonomic motor nerves
what is the mediastinum?
central compartment of thoracic cavity located between lungs
- it has different parts that have different structures
big structure = heart in middle mediastinum
what are phrenic nerves?
nerves C3,4,5 that innervate the diaphragm
- phrenic nerves runs ANTERIOR to root of lung all the way down to diaphragm (earlier in alphabet than vagus nerve so at front)
where does vagus nerve run in relation to root of lung?
- vagus nerve runs posterior to root of lung
what is the pericardium layers? (from outside -> inside)
- fibrous pericardium - tough layer
- serous pericardium has 2 parts: parietal serous pericardium (in contact with fibrous pericardium) and visceral serous pericardium/epicardium (in contact with developing heart)
where is pericardial cavity?
in between parietal serous pericardium and visceral serous pericardium
what does visceral serous pericardium do?
secretes pericardial fluid into pericardial space
- the fluid lubricates surface of heart as it beats which reduces friction between layers of serous pericardium during contraction allowing heart to move smoothly within sac
what is cardiac tamponade?
= pericardial filled with blood (can occur a number of reasons e.g. trauma related, a tear etc) →cavity would fill with blood and that would put pressure on heart and prevent proper contraction (increase pressure in cavity putting pressure on heart and preventing beating properly)
what is pericardiocentesis?
procedure with removal of any abnormal fluid as abnormal fluid prevents normal contraction and we need to put needle in cavity to aspirate or take off abnormal fluid
where does pericardiocentesis take place?
in small area directly middle of chest where no overlying tissue above heart (such as lungs etc)
= you would insert needle at infrasternal angle (subcostal) and direct superiorly and posteriorly into pericardial cavity
what is transverse pericardial sinus?
a space within pericardial cavity that is located behind some of the great vessels
- you put finger behind pulmonary trunk, ascending aorta and finger tip will emerge from sinus anterior to superior vena cava
(surgeons use when trying to isolate great vessels in order to commence cardiopulmonary bypass)
where are the most proximal segments of the pulmonary trunk & ascending aorta?
enclosed in the pericardium, which blends with their adventitia a little further distally
what surface of heart is also called sternocostal surface?
anterior surface
what surface of heart is also called diaphragmatic surface?
inferior surface
what surface of heart is also called base surface?
posterior surface (back)
what border of heart do all the great vessels enter/exit?
superior border
where is apex of heart located?
5th left intercostal space in midclavicular line (mitral area)
what can shift the location of apex of heart?
cardiac enlargement (cardiomegaly) which often shifts the beat to the left
what are auricles of heart?
essentially they are extensions of atria that allow maximum filling of heart (there is R&L)
where is coronary groove?
between RA & RV - has coronary artery between groove
- indicates the surface marking for tricuspid valve
where is anterior interventricular groove?
between LV & RV - contains a branch of left coronary artery called LAD (left anterior descending) or anterior interventricular artery
what heart chamber makes up most of
a) posterior surface
b) inferior surface
a) left atrium
b) most of the ventricles
what is the coronary sinus?
= short venous conduit (channel) in posterior AV groove which receives deoxygenated blood from most cardiac veins and drains into RA
- main venous drainage from myocardium (heart muscle) that seperates base & diaphragmatic surface (back & bottom)
where is interatrial groove located?
posterior between LA & RA
what is azygos vein?
large vein that drains blood from posterior thoracic & abdominal walls and joins with superior vena cava
where is posterior interventricular groove?
between LV and RV - separates 2 ventricles on diaphragmatic surface of heart
what is the first branch of ascending aorta?
the coronary arteries
what are the branches of right coronary artery?
2 branches =
1. right marginal artery supplying right margin of heart
2. posterior interventricular artery
(much longer than left coronary artery)
where is right coronary artery found?
in coronary groove - RA
(withdraw right auricle to locate origin of vessel)
what are branches of left coronary artery?
main stem coronary artery branches into:
- left anterior descending artery (LAD)
- lateral or diagonal branch (supplying majority of anterior surface of heart)
- left marginal artery supplying left margin of heart
- circumflex artery which anastomose with branches of right coronary anterior on posterior surface of heart
where is main stem left coronary artery located?
in left AV groove between pulmonary trunk & left auricle
what groove seperates
a)anterior RA & RV
b)anterior RV & LV
c) posterior LA & RA
d) posterior RV & LV
a) coronary groove
b) anterior interventricular groove
c) interatrial groove
d) posterior interventricular groove
what seperates right and left side of heart?
septum
what are the 2 parts of the septum?
between atria = interatrial septum (position indicated by interatrial groove)
between ventricles = interventricular septum (position indicated by anterior interventricular groove)
what happens if hole/defect in septum?
this can lead to mixing of arterial and venous blood which can be life threatening problem as reduces oxygen content in arterial blood →hypoxaemia
what vessels open into right atrium?
- superior & inferior vena cave
- coronary sinus (much smaller)
what is oval fossa?
found in RA
(thumb tip like oppression associated with interatrial septum). embryological remnant of foramen ovale (a connection between R&L atrium from embryology of heart) = fosso ovalis
what is crista terminalis?
ridge of tissue →the division between smooth area of RA and roughened area caused by muscular bands (trabeculae carneae)
what are the names of the 4 valves?
- aortic valve
- pulmonary valve
- mitral/bicuspid
- tricuspid
where is the pulmonary valve?
between right ventricle and pulmonary trunk (when blood leaving to go to lungs)
where is the aortic valve?
between left ventricle and aorta
where is the mitral valve?
between LA & LV (also called bicuspid)
where is tricuspid valve?
between RA & RV
what valves are leaflet design and what does that mean?
mitral & tricuspid - atrioventricular valves
mitral→2 leafs & tendinous cords (attach to papillary muscles which are part of cardiac walls). we don’t want force of contraction to cause prolapse back up into atria so that’s why tendinous cords there (prolapse = body part fallen from normal position)
tricuspid →3 leafs
what makes the heart sounds?
closure of mitral & tricuspid = LUB (1st sound)
closure of pulmonary & aortic = DUB (2nd sound)
what valves are semilunar and what does that mean?
called semilunar due to half moon shape
what is the moderator band or septomarginal trabecula?
carries fibres of right bundle branch to the papillary muscle of the anterior cusp
what is general rule to find each auscultation point?
follow direction of normal blood flow through valve until the edge of sternum is located & auscultate there (since we can’t auscultate through bone)
*mitral valve is slightly different
where do you auscultate for each valve?
aortic = 2nd right intercostal space sternal edge
pulmonary = 2nd left intercostal space sternal edge
tricuspid = 4th left intercostal sternal edge (lower left sternal edge)
mitral = 5th left intercostal space midclavicular line
