2. The Heart as a Pump + Anatomy Flashcards
What is the principle pacemaker of the heart called?
Sino atrial node
Where is the sino atrial node located?
Right atrium
How long does electrical activity get halted at the AV node for?
120ms
What causes the first heart sound?
AV valve closing
What causes the second heart sound?
Outflow valves closing
What causes the outflow valves to open?
Ventricular pressure exceeding aortic pressure
What is the period of time during ventricular systole before the outflow valves open called?
Isovolumetric contraction
What causes the AV valves to open?
Ventricular pressure falling below atrial pressure
When does the rapid filling phase occur?
Start of diastole
What causes murmurs to be heard?
Turbulent blood flow
What causes turbulent blood flow?
A stenosed valve
An incompetent valve
At what point in th cardiac cycle would you be most likely to hear a systolic murmur caused by aortic stenosis?
Rapid ejection phase
What is stroke volume?
The blood that the heart ejects per beat (roughly 80ml)
How do you calculate cardiac output?
Stroke volume x heart rate
What makes up the left border and apex of the heart?
Left ventricle
What forms the right border of the heart?
Right atrium
What mainly forms the inferior border of the heart?
Right ventricle
The right atrium receives blood from the cardiac veins via what vessel?
The coronary sinus
Where does the coronary sinus lie?
Posterior atrioventricular groove
The left coronary artery arises from what?
The left aortic sinus
Parasympathetic activity to the heart is delivered by which nerve?
Vagus nerve
At what vertebral level does the abdominal aorta split into the common iliac arteries?
L4
What arteries split off of the brachiocephalic trunk?
Right subclavian
Right common carotid
