Cardiac Cycle, Action And Ecg

Question 1

Cardiac cycle

Answer 1

Directs blood flow through 🫀
Coordinated Sequence of contraction and relaxation
1 cycle = 1 heartbeat

Question 2

Diastole

Answer 2

Diastole= avv open, slv shut due to high p in pa and aorta
Blood flows into atria and ven

Question 3

Atrial diastole

Answer 3

Atrial systole= v relax,
remaining blood forced into v as walls atria squeeze and inc pressure

Question 4

Ventricular diastole

Answer 4

Ventricles s= a relax
av forced shut as high p ,Slv open, blood forced out v and enters arteries and aorta

Question 5

Need for coordination

Answer 5

Contractions synchronised for efficient pumping

Question 6

Electrical coordinatuon of cardiac cycle

Answer 6

Electrical Imp (wave of excitation) gen at SAN aka pacemaker
Wave spreads over atria walls
Atria contract (wave cannot pass =non-conducting tissue)
So passes to AVN, delayed (to allow atria to finish contracting)

Impulse passes down Purkyne tissue in septum and V contract from base upwards

Question 7

Ecg

Answer 7

Montior electrical activity of 🫀

Question 8

Types of ecg

Answer 8

Sinus rhythm =norm
Bradycardia = slow
Atrial fibrillation = a frew> v
Ectopic= 3rd early beat
Tachycardia = fast