Cardiovascular

Question 1

Middle mediastinum contents

Answer 1

-Pericardium, heart and roots of great vessels
-Pericardial sac and heart lies obliquely, approximately 1/3 to the right and 2/3 to the left of the midsternal line

Question 2

Pericardium

Answer 2

Fibrous pericardium- tough external layer, continuous with diaphragm and great vessels
Serous pericardium- membrane lining the internal surface of the fibrous pericardium (parietal layer); reflects at the great vessels to become the external layer of the heart (visceral layer)

Question 3

Pericardial cavity

Answer 3

-Space between parietal and visceral layers/ contains serous fluid
-Enables heart to move and beat in a frictionless environment

Question 4

Cardiac cycle

Answer 4

Diastole
-Ventricular relaxation and filling; semilunar valves closed
Systole
-Ventricular contraction and emptying; AV valves closed
1st heart sound= AV valve closure to prevent backflow into atria
2nd heart sound= semilunar valves closure to prevent backflow into ventricles

Question 5

Functions of fibrous skeleton of the heart

Answer 5

1. Attachment for all valves and myocardium
2. Keeps valve orifices patent
3. Electrically isolates atria from ventricles

Question 6

Venous drainage of the heart: cardiac veins

Answer 6

-Cardiac veins drain into the coronary sinus > into R atrium
-Great cardiac vein: drains area of heart supplied by LCA
-Middle and small cardiac veins: drains area of heart supplied by the RCA