3.2 Physiology and Anatomy of Cardiovascular System Flashcards
What are the 4 chambers of the heart?
- Right atria
- Right ventricle
- Left atris
- Left ventricle
What are the 4 valves of the heart?
- Tricuspid (right)
- Pulmonary
- Bicuspid (left)
- Aortic
What are the 6 great vessels of the heart?
- Superior vena cava
- Inferior vena cava
- Pulmonary trunk
- Right pulmonary artery
- Left pulmonary artery
- Aorta
Closure of heart valves cause vibrations in adjacent heart walls + blood, making the iconic heart sound “lub-dub”. What are the valves involved?
Closure of aortic valves at start of ventricular systole
Closure of semilunar valves at end of ventricular systole
Blood is pumped through two circuits, what are they?
Pulmonary circuit = blood vessels that carry blood to and from lungs
Systemic circuit = blood vessels that carry blood to and from the rest of the body
Where do the left coronary artery, the right coronary artery, and the great cardiac vein stem from?
Left = aortic sinus, jsut above aortic valve
Right = aortic root, right above aortic valve
Great cardiac vein = coronary sinus, right atria
The cardiac conductive system is made from specialised cardiomyocytes connected through gap junction proteins called connexin 43. What are te components of this system?
- Sinoatrial node
- Intermodal pathway fibres
- Atrioventricular node
- AV bundle
- R and L bundle branches
- Purkinje fibres
What are the meanings of endocardium, myocardium, space-pericardial, and epicardium?
Endocardium = heart endothelium
Myocardium = cardiac muscle cells intrinsically able to generate + conduct impulses
Space-pericardial = between parietal and visceral
Epicardium = double walled sac
The cardiac cycle has two phases of stroke pump: the diastole and systole. What are the differences between them?
Diastole = heart chambers passively fill with blood returning from veins
(bicuspid + tricuspid valves open, pulmonary + aortic valves closed)
Systole = active contraction to pump blood to arteries
(bicuspid + tricuspid valves = closed, pulmonary + aortic valves = open)
What is the cardiac cycle facilitated by?
Intrinsic pacemaker regions
Must be able to vary output to meet bodies need
Needs source of energy = high oxygen demand + ATP
What is cardiac output?
Amount of blood the heart pumps in 1 minute
Stroke volume X beats per minute (BPM)
What is Starling’s Law?
Preload increase = cardiac stroke volume increase = increased cardiac output
Starling’s equation / forces are an equation which demonstrates what?
Role of hydrostatic + oncotic forces in fluid movement across capillary membrane
Useful in explaining oedema
Blood pressure is the pressure of blood on the arterial wall. What are the two types of blood pressure value?
- Diastolic pressure = when heart relaxes, bottom of pressure
- Systolic pressure = when heart contracts, top of pressure
Blood pressure = cardaic output X peripheral resistance. How is this regulated?
Blood volume = renin-angiotensin pathway
Heart Rate = sympathetic nervous system
Vessel resistance = sympathetic nervous system
Cardiac control is managed short-term and long-term via two different systems / pathways. What are they?
- Autonomous nervous system via BARORECEPTOR REFLEX = senses + regulates short-term chanegs in blood pressure
- RENIN-ANGIOTENSIN pathway = hormonal control system for long term regulation of blood pressure
The liver, kidneys, and lungs excrete important factors for the renin-angiotensin pathway, what are they?
Liver = Angiotensinogen
Kidney = Renin (when arterial blood pressure is down)
Lungs = Angiotensin Converting Enzyme (ACE)
How does the renin-angiotensin pathway lead to long-term increases in blood pressure?
- Angiotensinogen + renin = angiotensin
- Angiotensin + ACE = Angiotensin II
- Angiotensin II activates processes in adrenal cortex + brain to increase arterial pressure + blood volume
What are the brain mediated processes in the renin-angiotensin pathway that lead to increases in arterial pressure + blood volume?
- Encourages thirst
- Produces vasopressin = kidney produces more renin and reabsorbs H2O + NaCl (useful when dirnk unavailable)
What are the brain mediated processes in the renin-angiotensin pathway that lead to increases in arterial pressure + blood volume?
- Encourages thirst
- Produces vasopressin = kidney produces more renin and reabsorbs H2O + NaCl (useful when dirnk unavailable)
- Vasopressin also affects blood vessels = vasoconstriction
How does the adrenal cortex increase arterial pressure + blood volume in the renin-angiotensin pathway?
- Produces aldosterone
- Aldosterone acts similar to vasopressin = kidney produces renin and reabsorbs H2O + NaCl
