Card Set Information
Bio_Mechanical Engineering Course
What are the general names for blood vessels and relative pressures?
Arteries - Deliver blood to the organs from the heart (80mmhg - 120mmhg)
Veins - Deliver blood to the heart (7 mmhg)
Describe some pathologies which can arise from faulty heart valves.
Left side output reduced
Right side output reduced
Ascites (Abdominal Edema)
What is the maximum diffusion distance between a capillary and a cell?
300 - 500 micrometers
What are the blood vessels which serve the large blood vessels called?
What are the names of the heart valves?
LO - Aortic Valve
LI - Mitral Valve (Bicuspid)
RO - Pulmonary Valve
Ri - Tricuspid Valve
Give the parts of the Cardiac Cycle
Distole (60% of time)
1) Pv ~ 0, A-c, M-o
2) Pv up toward 7mmhg and the flaccid wall begins to stretch until mycardial stretch balances filling pressure.
Systole (40% of time)
3) Contraction begins at the apex with a twist
+ M-c and A-c
+ Isovolemic systole, P up, Vol constant
4) A-o, Pv goes up to 120 mmhg, then quickly drops back to zero
What are the ways to increase the cardiac output?
CO = Stroke Volume * BPM
1) Increase BPM
-Chemical stimuli (Norepinephrine - "Adrenalin")
2) Increase STV
-Increase contraction of upstream veins. Preload therefore Pv goes up and stretch in the ventricular walls increases.
-Decrease the arterial pressure. Afterload drops and residual volume drops.
What are the steps of cardiomyocyte polarization?
1) Energy is spent (ATP) to pump Na out of the cell which draws K in and charges the cell to -90mv
2) Spontaneously, the membrane switches from an insulator to a conductor and Na rushes in and K out. Voltage rises and overshoots zero.
3) The acceleration of the current causes an electrical field and a magnetic field for each cell.
How does the heart fire electrically?
1) CMC in the sinoarterial node depolarize at a faster rate and initiate electrical diastole through atrium.
-This initiates the "atrium kick"
-Valve rings insulate ventrical
2) Depolarization is allowed into the ventricle with a delay through the atrial ventricular node.
3) Depolarization is sent to the apex through the Purkinje fibers.
4) Electrical systole begins and the heart contracts and twist from the apex upward.