Cardiovascular anatomy Flashcards
Describe the path of pulmonary circulation
right –> lungs –> left
Describe the path of systemic circulation
left–> tissues –> right
What is cardiac arrest?
When heart stops
What is heart failure?
When heart doesn’t pump well enough
Where is the heart?
Thoracic cavity
In middle mediastinum
2/3 on left side, 1/3 on right side
Describe how the mediastinum is divided
Superior
Inferior - anterior
- middle
- posterior
What is the pericardium?
Sac surrounding heart
Name the two layers of the pericardium
fibrous pericardium
serous pericardium
Describe the fibrous pericardium
Outer layer, tough, thick and fibrous
Prevents heart overfilling and gives some protection
Haemopericardium can result in cardiac tamponade
What is cardiac tamponade?
When heart is under pressure and cannot pump correctly
Can lead to cardiac arrest
Describe the serous pericardium
Thin, inner membrane which secretes serous fluid
Covers heart, but heart is not actually inside this membrane
Name the two parts of the serous pericardium
Visceral - touching heart
Parietal - touching fibrous pericardium
The two parts are continuous ( a loop )
Why is the heart not inside the pericardial cavity?
As heart grows, it pushes into serous pericardium from outside and serous layer never breaks
Name and describe the three layers of heart tissue
Epicardium - serous pericardium
Myocardium - muscle
Endocardium - internal lining, continuous with tunic intima lining of blood vessels
What does the inferior surface of the heart rest on?
Diaphragm
What divides the oxygenated and deoxygenated blood in the heart?
Septum
What do the valves in the heart do?
Prevent blood flowing in the wrong direction
Which valve sits between the right atrium and ventricle?
Tricuspid valve
Which valve sits between the right ventricle and pulmonary trunk?
Pulmonary valve
Which valve sits between the left atrium and ventricle?
Mitral (bicuspid) valve
Which valve sits between the left ventricle and aorta?
Aortic valve
Where is an electrical impulse initiated?
Sino-atrial node
Describe the route of an electrical impulse in the heart
SA node to
AV node in atrioventricular septum down
right and left bundles in interventricular septum spreading through
myocardium via conducting fibres
What does the fibrous part of the septum do?
Act as electrical insulator and ensures there is only one point of electrical conduction between atrial and ventricular myocardium
