Cardiac Physiology Flashcards
What are the 2 different types of vascular systems?
Closed circulatory system
Vertebrate cardiovascular system
What is a vertebrate cardiovascular system?
Multi-chambered heart that contracts to transport blood in a series of vessels.
What are the main types of circulation within the cardiovascular system?
Arterial circulation
Venous circulation
Pulmonary circulation
What is the atria responsible for?
Responsible for receiving blood from the body (from the vena cava) or lungs (from the pulmonary vein)
What are the ventricles?
They pump blood from the heart to the body (LV)
From the heart to the lungs (RV)
Where is the mitral valve?
Cuspid/Atrioventricular valve
Mitral valve is in between the LEFT atrium and ventricle.
It regulates the flow of blood from the lungs to into the L. ventricle
Where and what is the role of the brachiocephalic artery?
Is one of the three great vessels of the aortic arch, that supplies blood to the right arm, head and neck
What role does the left atria have?
It receives oxygenated blood from the lungs and pumps it into the left ventricle
What is the role of the right atria?
It received Deoxygenated blood from the body and pumps it into the right ventricle to the lints for an oxygen supply.
What is the intraventricular septum?
The dividing wall between the ventricles
What are the names of the 2 atrioventricular valves on the left and right side?
Left = Mitral valve
Right = Tricuspid valve
What purpose does the semilunar valves serve?
They prevent the backflow of blood
Where are the semilunar valves?
In the ventricles and arteries leaving the heart (aortic and pulmonary valve)
What are the three main cell types in the heart?
Cardiomyocytes
Fibroblasts
Endothelial cells
What is the function of cardiomyocytes?
The contractile function of the heart that enables the pumping of blood around the body.
What are fibroblasts responsible for?
They are responsible for collagen production.
What are the 3 craniums of the heart wall?
Myocardium
Pericardium
Endocardium
When does myocardial perfusion occur?
Only occurs during diastole (cardiac relaxation)
What is the role of the cardiac arteries?
They supply blood throughout the myocardium
When does blood fill in the coronary arteries?
Blood fills when the arteries are relaxed
What is the difference between the left and right coronary arteries?
The left = supplies blood to the left side including the Left anteriors descending artery and the circumflex systems
The right = right side (including the SAN, AVN)
What is atherosclerosis?
Where arteries become clogged with fatty substances (plaques)
What is diastole?
Filling of blood in the heart.
Its also referred to as the relaxation period
What is systole?
Pumping of blood in the heart.
Its also known as the contraction phase
What is cardiac output?
The volume of blood expelled from the left ventricle in each beat.
Also, The volume of blood pumped by one ventricle per minute
What is the ejection fraction (EF)?
What is the EF usually?
The % of blood expelled from the left ventricle at each beat.
(Usually 60%)
What role does the sinoatrial node have?
It initiated the electrical impulses. - stimulates contraction
(In the right atrium)
What role does the Atrioventricular node have?
The delay node that enables the ventricles to fill with blood
What are the bundle branches?
The electrical conductance pathway of the heart through the L & R myocardium. This includes the Bundle of His.
What are the Purkinje Fibres?
They are specialised cardiac myocytes, responsible for translating electrical impulses into a contractile force
What does the P wave interval represent?
Atrial depolarisation
What does the QRS complex represent?
Ventricular depolarisation
What does the T wave represent?
Ventricular repoarisation
What is the equation for cardiac output?
CO - Heart rate (beats/min) X Stroke volume (ml/beat)
Why is the ejection fraction never 100%?
There is always some blood remaining in the heart
Where does the inferior vena cave bring blood from?
The lower limbs and abdomen
Where does the superior vena cave bring blood from?
From the upper limbs, eyes and neck