Exam II Vocab 2

Card Set Information

Exam II Vocab 2
2012-04-03 09:59:55
Exam II Vocab

Cardiac Cycle
Show Answers:

  1. Atrial Presure Curve:
    A wave
    C wave
    V wave
    • A wave: (atrial contraction), pressure low, then P wave comes, the pressure goes up a little, squeezing the 30% of blood into ventricle
    • C wave: (ventricular contraction), ventricular pressure goes up really high--->AV valve shuts off, creats lub, ventricular pressure shoots up, bulges the valve up into the atrial, the this increases the pressure in atria stil
    • V wave (slow pressure build-up in atria): Ventrical contraction, but relaxation of atria--->Blood return from venous return
  2. What happens when ventrical relaxes and ventricle pressure goes below atria pressure?
    • 1. AV valves open
    • 2. 70% blood falls back to ventricle, venus return, blood goes to atria, ventricle pressure below atria
  3. ventricle pressure
    • Ventricular pressure (Systole)
    • AV shuts (lub) pressure builes up, blood is trapped, isometric contraction
    • -When the pressure in ventricle is above aorta, aortic valve opens,
    • blood squeezes through to aorta, T wave, and ventricle relaxes, pressure goes down to zero, blood starts to come back to ventricle, aorta snaps shut
  4. Autonomic Nerves on Pacemaker potential in SA node
    • Increase the slope with sympathetic
    • Decreae the slope with parasympathetic- longer hypopolarization, slows the heart rate
  5. IMPORTANT: Parasympathetic DOES NOT CHANGE THE FORCE of the contraction, it is a chronotropic change, meaning it CHANGES the rate by slowing it
    -Sympathetic: Makes the force stronger
  6. Sympathetic innervation of the SA
    • 1. Opens the HCN by epi and norepi stimulation( That means Na and Ca channels
    • -Hyperpolarization
    • -More cardiac cycles per minute)
  7. 4 Extrinic regulation of the heart
    • 1. Neurally controlled
    • 2. Major center in CNS is locatd in medulla (Pool of neurons there with same function)
    • 3. Endocrine
    • 4. Frank Starling Law (Sympathetic)
  8. Know Stroke Volume
    The amount of blood squeezed out of heart during a contraction
    • Stroke volume= end-diastolic - end-systolic
    • (135-65=70ml)
  9. End diastolic
    The volume of blood in ventricle at the end of diastolic (Just before it contracts) 135ml
  10. End-systolic
    • After contraction volume
    • -65 ml in heart
    • This is due to the backflow before the semilunar shuts
  11. Valsalva maneuver
    Forced expiration on closed glottis, put a lot of pressure in thoracic cavity-Closed the great vein off
  12. hyperkalemia
    Potassium is up, decrease contraction
  13. Arethmias
    Low potassium
  14. Temperature up-->heart rate up
  15. Korotkoff sound
    • When the cuff is above systolic pressure, the artery is constricted,
    • When it's between systolic and diastolic, blood flow is turbulent and Korotkoff sounds are heart with each systole.

    • No sound at 140
    • First sound at 120, that's the systolic pressure
    • Second sound, 100, is the cuff pressure
    • Third sound, diastolic pressure
  16. MAP
    Mean arterial pressure (drives blood into the circulatory system): diastolic + 1/3 pulse pressure
  17. Pulse pressure
    (and relate this in the equation for MAP)
    Pulse pressure:This is the pressure difference we're sensing when the arteries are engorged with blood during systolePulse pressure=Systolic-Diastolic =40 mmHg