The heart

Question 1

What are the 2 reflections of the pericaridium

Answer 1

Transverse pericardial sinus
posterior to the ascending aorta and pulmonary artery and anterior to superior vena cava

Oblique pericardial sinus
zone of reflection around the veins is J-shaped. The sinus is posterior to the left atrium

Question 2

What is cardiac tamponade?

Answer 2

1. Rapid accumulation of fluid in pericardial sac
2. pericardial effusion
3. cardiac tamponade
4. biventricular failure

Question 3

What is the difference between atrioventricular and semilunar valves?

Answer 3

Semilunar do not have tendons like the atrioventricular valves

Question 4

Where can heart valves be asculated?

Answer 4

Aortic - Right sternal edge 2ndintercostal space;
Pulmonary - Left sternal edge 2ndintercostal space;
Tricuspid - Left sternal edge 5thintercostal space;
Mitral - Mid-clavicular line 5th intercostal space.

Question 5

What are the main features of the right atrium?

Answer 5

SVC, IVC, coronary sinus

Fossa ovalis - embryological remnant of the foramen ovale, which in the foetus allowed oxygenated blood to bypass the nonfunctional lungs (r.atr–>l.atr)

Crista terminalis – smooth muscular ridge beginning at the roof of the right atrium and extending down to the anterior lip of the IVC. It separates the right atrium into 2 spaces

Right auricle – ear-like, conical, muscular appendage of the atrium

Question 6

What are the structures of the right ventricle?

Answer 6

Papillary muscles, attached to chordae tendinae and trabeculae carneae.

Tricuspid valve, (connects with RA) - has three leaflets, anterior, septal and posterior (SAP)

Pulmonary valve: left, right and anterior semilunar cusps

Question 7

What happens to valves as the ventricles contracts?

Answer 7

Papillary muscles contract and pull on the chordae tendinae, this prevents eversion of the tricuspid valve cusps - keep the valve closed during ventricular contraction

Each semilunar cusp forms a pulmonary sinus
After ventricular contraction, the recoil of the blood fills these sinuses and forces the cusps closed – preventing backflow into the right ventricle

Question 8

What are the main features of the left atrium?

Answer 8

Has 2 halves:
Posterior half – inflow portion which receives blood from the 4 pulmonary veins (2 from each lung)

Anterior half – continuous with the left auricle (which is an atrial appendage similar to the right auricle)

Mitral valve – connects with LV

Valve of the foramen ovale – depression in the interatrial septum, during development this is open and allows blood to pass between the left atrium and the right atrium

Question 9

What are the main features of the left ventricle?

Answer 9

Mitral valve has 2 cusps – anterior and posterior.

Thick myocardium

Trabeculae carnae and papillary muscles are attached to the chordae tendinae

Aortic valve: right, left and posterior semilunar cusps
recoil automatically forces blood into the coronary arteries

Question 10

What are sulci?

Answer 10

Internal partitions separating the chambers of the heart are reflected as grooves known on the external surface of the heart

Coronary sulcus – separating atria from ventricles
Atrioventricular sulcus – separating the ventricles from each other

Question 11

What vessels does the coronary sulcus contain?

Answer 11

right coronary artery, circumflex branch of left coronary artery
small cardiac vein, coronary sinus,

Question 12

What vessels does the atrioventricular sulcus contain?

Answer 12

Anterior interventricular sulcus: contains anterior interventricular artery (LAD – left anterior descending) and great cardiac vein

Posterior interventricular sulcus: contains posterior interventricular artery (PDA - posterior descending artery) and middle cardiac vein

Question 13

What are the branches of the right coronary artery?

Answer 13

Sino-atrial nodal artery
Right marginal artery
Posterior descending artery

Question 14

What are the branches of the left coronary artery?

Answer 14

Left main branches:
Circumflex artery
Left anterior descending (LAD)

Question 15

What is the course of the right coronary artery and its branches?

Answer 15

1. early atrial branch travels in between the right auricle and ascending aorta, wraps posteriorly around the superior vena cava and gives off a sino-atrial nodal branch, supplying the SAN
2. inferiorly along the coronary sulcus it gives off a right marginal artery
3. along the base of the heart it gives off its major branch – the posterior descending (aka posterior interventricular) artery which travels along the posterior interventricular sulcus. This mainly supplies the posterior and inferior part of the heart

Question 16

What does the right coronary artery supply

Answer 16

right atrium, right ventricle, SAN, AVN, posteroinferior 1/3rd of interventricular septum and some of the posterior part of left ventricle

Question 17

What does the left coronary artery supply

Answer 17

travels from the left aortic sinus in between the pulmonary trunk and left auricle, as it emerges from behind the pulmonary trunk it divides into it’s two terminal branches

1. Left anterior descending artery (LAD); descends towards the apex via the anterior interventricular sulcus
   - supplies most of the anterior interventricular septum and the left ventricle, and is therefore considered the most critical artery in terms of myocardial blood supply
2. Circumflex artery; courses towards the left and around the heart in the coronary sulcus, it usually ends before reaching the posterior interventricular sulcus.
   - left marginal artery arises from it.
   - mainly supplies the left atrium and the posterolateral part of the left ventricle

Question 18

What does the left coronary artery supply

Answer 18

most of the left atrium, left ventricle, atrioventricular branches and bundles

Question 19

What are the coronary veins?

Answer 19

Great cardiac vein
Middle cardiac vein
Small cardiac vein
Posterior cardiac vein