heart

Question 1

chambers of heart

Answer 1

RA - blood returns via SVC and IVC and coronary sinus
LA - blood returns via pul veins
RV - outflow to pul trunk
LV - outflow to ascending aorta

Question 2

valves

Answer 2

tricuspid AV valve - held to wall by cordae tendinea which are embedded in the wall by capillary muscle - prevent eversion
tricuspid - 3 cusps: anterior, posterior, septal between them
semilunar valve made of 3 sinuses/envaginations - when together they will form cylinder
aortic valve - coronary aortic sinus - wall in valve have holes for coronary arteries, one cusp doesn’t have hole - non-coronary aortic sinus
mitral valve - anterior and posterior valve

Question 3

RA

Answer 3

coronary vein return deoxygenated blood - go into RA at coronary sinus
blood travel to RV through tricuspid valve

Question 4

LA

Answer 4

there is a window between L and R A - bypass of lungs in foetus - valve of foraman ovale - close up at birth = fossa ovale
pul trunk out of back
aytrioventricular valve - mitra

Question 5

RV

Answer 5

AV valve - tricuspid valve

blood through semilunar valve to pul artery

Question 6

LV

Answer 6

has a net structure - trabeculae carneae

Question 7

damage to valve

Answer 7

causes regurgitation

blood flow back into atria

Question 8

cardiac arrest and MI

Answer 8

CA - electrical event

MI - ischemic event - blood supply issue

Question 9

conducting system of the heart

Answer 9

SAN - specialised cells - cant see in the DR
atria contract ms before ventricles
purkinje fibres turn back on self - cause depolarisation - contract from bottom

Question 10

somatic spinal nerves

Answer 10

posterior and ventral/anterior horn
motor nerves travel to skeletal muscle
sensory to body wall
spinal nerves - mix of afferent and efferent fibres
segmental nerves - combine to form plexi supplying cervical, brachial and lumbosacral

Question 11

what is the pericardium

Answer 11

fibroserous sac surrounding the heart and great vessels
in middle of inferior mediastinum up to the exit of the aorta
fibrous pericardium blends with the outer wall of the aorta and vessels
serous: parietal (line fibrous) and visceral (line heart)

Question 12

pericardial sinus

Answer 12

infections can occur
transverse pericardial sinus - separates arteries from veins - used clinically to limit the outflow from the heart
oblique sinus - visceral pericardium reflects back on itself to be the parietal layer

Question 13

formation of the pericardial sinuses

Answer 13

heart starts as tube and folds in on itself

Question 14

orientation of the heart

Answer 14

anterior - surface close to sternum 
diaphragmatic surface 
apex - L ventricle, 5th ICS 
R and L pulmonary surfaces 
base 
inferior and obtuse margins

Question 15

Left coronary artery

Answer 15

circumflex branch of the L coronary artery

anterior interventricular branch of L coronary artery

Question 16

R coronary artery

Answer 16

common: posterior interventricular branch of R coronary artery
less common: posterior interventricular branch of circumflex branch of L coronary artery

Question 17

coronary veins

Answer 17

interventricular veins
all drain into coronary sinus
drain into RA - bring deox blood

Question 18

branches off the aorta

Answer 18

brachiocephalic trunk - supply R side of the head and neck
L common carotid artery
L subclavian artery

Question 19

main veins

Answer 19

R and L brachiocephalic veins drain into the SVC

Question 20

intercostal vessels

Answer 20

from aorta at front and internal thoracic vessels at the front
aorta doesn’t reach ICS 1 and 2 - different supply
supply from subclavian arteries - supreme intercostal arteries
happen in coarctation of aorta - squashed

Question 21

descending aorta

Answer 21

artery to lung
posterior intercostal vessels
back of cest wall from ICS 3