phys winter #2.txt

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phys winter #2.txt
2011-01-21 17:08:18
phys test winter

phys test #2 winter
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  1. What percent of EDV does atrial systole account for?
  2. What are the three factors that affect contractility?
    • ANS
    • Hormones (catecholamines)
    • Calcium
  3. what are two methods of increaseing RV pressure and SV?
    • negative intrathoracic pressure
    • increase Central Venous Pressure
  4. What are the effects on FFA and glucose with and without insulin?
    • W/O: lipolysis = FFA circulation and use in heart
    • W/: no lipolysis = glucose use in heart
  5. What are the goals of the 4 pharmacological methods to increase glucose oxidation? What are the drugs associated with each?
    • 1) decrease B-oxidation: Ranolazine, trimetazidine
    • 2) decrease FFA uptake: etomoxir, oxfenecine
    • 3) decrease/block AcetylCoA from Mitochondria: Carnitine
    • 4) Activate glucose metabolism: Dichloroacetate
  6. What are the three reasons for S2 widening split?
    • pulmonary stenosis
    • RV failure
    • Right branch block/failure
  7. What is the reason for S2 narrowing or disappearing?
    Left branch block/failure
  8. What causes a paradoxical split and what does paradoxical split mean?
    • Aortic stenosis
    • ***Pulmonary valve closes before Aortic valve
  9. In the cardiac cycle, how does aortic stenosis affect the graph?
    • Cause LVP to rise and the Aortic pressure to slightly drop
    • mid-Systolic murmur
    • ***cardiac hypertrophy and paradoxical split
  10. In the cardiac cycle, how does mitral valve stenosis affect the graph?
    • LAP greater than LVP during filling times
    • diastolic murmur
    • ***Pulmonary congestion
  11. In the cardiac cycle, how does aortic regurgitation affect the graph?
    • rate of decline in aortic pressure is greater
    • Slight increase in LV pressure, but countered by SV
    • ***congestion and widening pulse pressure
  12. In the cardiac cycle, how does mitral regurgitation affect the graph?
    • holosystolic murmur
    • LAP increases upon Ventricular systole
    • **venous congestion
  13. What are the 5 determinants of afterload on Cardiac performance? AMP VA
    • Arterial pressure
    • Mass of blood in aorta
    • Peripheral vascular resistance
    • Viscosity of blood
    • Arterial wall complaince
  14. How does the Frank Starling law compensate for Afterload?
    • Even though ESV is high, the ventricle will still fill up normally to restore SV
    • LVSW increases
  15. What factors increase contractility of the heart? (heart ACHe
    • ANS
    • Ca
    • Hormones
  16. What happens to fiber length as EDV increases?
    Fiber length is stretched so there is higher contractility
  17. How does the SNS affect contractility?
    Release of NE causes positive inotropic effect = increased SV at given EDV
  18. What happens to SV as contraction increases?
    • The SV increases so there is less ESV
    • Ejection fraction increases as well
  19. What is Treppe modulation?
    As HR increases, calcium is trapped and used for higher contractility
  20. What is the relationship b/t HR and CO?
    • - HR up to 150 = no change in CO since HR and SV are inverse
    • - HR > 150 = change in CO due to SNS to maintain or increase SV
  21. What increases during exercise, pressure or volume?
    Volume b/c pressure is too costly
  22. What are the exogenous fuels for the heart?
    • Glucose
    • lactate
    • fatty acids
    • ketone bodies
  23. What are the endogenous fuels for the heart?
    • Glycogen
    • Triglycerides
  24. What is the percentage of fuel provided by carbs and fatty acids?
    • Carbs= 30%
    • Fatty Acids = 70%
  25. What are the four sources of glucose metabolism?
    • Glycolysis
    • glucose oxidation
    • lactate oxidation
    • glycogen stores
  26. What are the four sources of FA metabolism?
    • Triglyceride lipolysis
    • Beta-oxidation of FA
    • chylomicrons oxidation
    • ketone body oxidation
  27. During fasting, what are the three things caused by low insulin?
    • lipolysis
    • FFA circulation
    • FFA uptake
  28. During fed state, what are the three things caused by high insulin?
    • lipolysis inhibition
    • glucose uptake
    • glucose use
  29. Explain the Randle cycle of the heart?
    • Increased FFA
    • Enter the mitochondria via CPT
    • oxidized to Acetyl-Co-A = PDH inhibition
    • oxidized to Citrate = PFK
    • PFK inhibition = HK inhibition by G6P = glucose stored
  30. What is the result of inhibiting glucose oxidation?
    LV failure
  31. Why is diabetes dangerous for the heart?
    No insulin or IR = all FA use for heart and no glucose use = LV failure
  32. What happens to FFA circulation during and after surgery?
    Increased and used in heart
  33. What is the function of Ranolazine and trimetazidine?
    inhibit B-oxidation
  34. What is the function of etomoxir and oxfenicine?
    inhibit CPT shuttle into mito
  35. What is the function of extra carnitine derivatives?
    buffer Acetyl-CoA
  36. What is the function of dichloroacetate?
    stimulate PDH
  37. What wave determines Snus Rhythm?
    • P-wave
    • **Depressed in V1, V2
    • **Positive in all others