Into to CVS Flashcards
Why do we need a CVS?
Diffusion of oxygen would take far too long- we are too big
The area of exchange between capillaries and a tissue is generally large and depends on….
Capillary density
More metabolically active tissues have …. capillary density
Higher
What determines the concentration gradient between capillaries and tissues?
Rate of tissue usage
Rate of blood flow
What is the rate of blood flow also known as?
Perfusion rate
Which organs require high and constant perfusion rates?
Brain and kidneys
What organ needs a high flow that increases with exercise?
The heart
Blood flow is increased to the ….. muscle in exercise but increased to the ….. after a meal
skeletal
gut
Does the total blood volume equal the circulating volume in a minute for the average man?
Yes- 5l/min at rest
How much can the blood flow increase by in exercise?
5 times
What cardiac border is inline with the second intercostal space?
Base of heart
Where is the apex of the heart in terms of surface anatomy?
Mid-clavicular line 5th intercostal space
What is fibrous around the heart? Why is this clinically significant?
The pericardium- no give so if pressure rises due to fluid accumulation in the pericardial cavity the heart is compressed - cardiac tamponade
Name the 4 layers of the pericardium.
Visceral - close to the myocardium
Pericardial cavity
Parietal layer
Fibrous layer
What procedure is performed in cardiac tamponade?
Pericardiocentesis
Where is the transverse pericardial sinus?
Between the pulmonary artery and the aorta.
Whats the oblique sinus?
Pericardial reflections on to the pulmonary veins
Where do you connect a Heart lung bypass machine and what so you clamp?
Connect ascending aorta and inferio vena cave to the machine
Clamp the aorta proximally to the heart from the tube of the machine.
What froms a lot of the anterior and inferior heart?
Right ventricle
What chamber wall forms the lateral left border of the heart?
Left ventricle
Name the branches of the left coronary artery
Left anterior descending
Left marginal artery
Circumflex branch
What are the branches of the right coronary artery?
Right marginal artery
Atrio ventricular nodal artery
Posterior inter ventricular artery
Small middle and great cardiac veins all drain to?
Coronory sinus
Which surface of the heart is the coronary sinus on?
Posterior under the pulmonary veins.
