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DIRECTIONS: Each of the questions or incomplete statements below is followed by five suggested answers or completions. Select the one that is BEST in each case.

1. From the pressure-volume loop illustrated above, one can determine that the beginning of ventricular isovolumetric relaxation is associated with a ventricular pressure of approximately

   (A) 90 mm Hg

   (B) 130 mm Hg

   (C) 50 mm Hg

   (D) 10 mm Hg

   (E) 140 mm Hg

2. From the pressure-volume loop illustrated above, one can determine that the peak of the R wave of the electrocardiogram is associated with a ventricular pressure of approximately

(A) 90 mm Hg

(B) 130 mm Hg

(C) 50 mm Hg

(D) 10 mm Hg

(E) 140 mm Hg

 

3. If ventricular preload and contractility remain unchanged, an increase in afterload will

   (A) decrease aortic diastolic pressure.

   (B) decrease ventricular end diastolic volume (EDV).

   (C) increase ventricular end systolic volume (ESV).

   (D) increase stroke volume.

   (E) decrease ventricular end systolic pressure (ESP).

    

4. If left ventricular end diastolic volume (EDV) decreased while left ventricular end systolic volume (ESV), heart rate and total peripheral resistance (TPR) all remained unchanged, which of the following must also be true:

   (A) ventricular contractility decreased.

   (B) mean aortic pressure decreased.

   (C) afterload increased.

   (D) venous return increased.

   (E) stroke work increased.

    

5. The vasculature is connected to a mechanical pump that has an output of 10 L/min. Venoconstriction is pharmacologically induced causing mean circulatory filling pressure (MCFP) to increase from 7 to 9 mm Hg while total peripheral resistance remains unchanged. At the new steady state, this causes

   (A) a decreased pressure difference across the total peripheral resistance.

   (B) the cardiac output curve to shift upward and to the left.

   (C) a decrease in the maximum output that can be produced by the pump.

   (D) both arterial and central venous pressure to be increased by 2 mm Hg.

   (E) the pressure difference across the total peripheral resistance to be increased by 2 mm Hg.

    

6. In a Starling heart-lung preparation, heart rate and total peripheral resistance (TPR) are held constant and venous return is doubled. At the new steady-state, ventricular end diastolic volume (EDV) is decreased. One can conclude that

(A) atrial pressure increased.

(B) contractility decreased.

(C) mean aortic pressure remained unchanged.

(D) mean coronary blood flow decreased.

(E) stroke work increased.

7. If surface pressure on the heart is increased above normal, which of the following statements is true:

   (A) Ventricular contractility is decreased.

   (B) Cardiac output as a function of ventricular end diastolic volume (EDV) remains unchanged.

   (C) Preload produced by any given atrial pressure is greater than would be produced under normal surface pressures.

   (D) Afterload is increased

   (E) The relationship between central venous pressure and ventricular muscle fiber length remains unchanged.

    

   

8. When the new cardiovascular state is compared to the initial cardiovascular state in the preceding figure, one can conclude that

   (A) cardiac output increased.

   (B) contractility increased.

   (C) mean arterial pressure decreased.

   (D) mean circulatory filling pressure increased.

   (E) ventricular end diastolic volume increased

9. When the new cardiovascular state is compared to the initial cardiovascular state in the above figure, one can conclude that

   (A) blood volume decreased.

   (B) atrial pressure decreased

   (C) venoconstriction decreased

   (D) heart rate increased.

   (E) total peripheral resistance (TPR) increased

10. The new cardiovascular state in the proceeding figure could be produced by

    (A) intravenous injection of an alpha adrenergic agonist.

    (B) intravenous injection of a cardiac glycoside and an alpha adrenergic antagonist.

    (C) intravenous injection of muscarinc and beta adrenergic antagonists.

    (D) stimulating the carotid sinus nerves.

    (E) intravenous infusion of plasma

11. Electrical stimulation of the carotid sinus nerve will result in

    (A) increased heart rate.

    (B) increased arteriolar contraction.

    (C) decreased unstressed volume.

    (D) increased firing rate of cardiac parasympathetic efferent fibers.

    (E) increased cardiac contractility

12. Cerebral blood flow

    (A) is more sensitive to arterial concentration of H+ than it is to Pco2.

    (B) is significantly decreased by a fall in carotid sinus perfusion pressure from 100 to 80 mm Hg.

    (C) at low levels may damage the blood-brain barrier.

    (D) demonstrates pressure-flow autoregulation at perfusion pressures up to 200 mm Hg if noradrenergic fibers innervating the cerebral arteries are stimulated.

    (E) is unaltered by changes in Po2.

13. Vascular beds that increase their blood flow as metabolism of the surrounding tissue increases are demonstrating

    (A) extrinsic control by the vasomotor center.

    (B) active hyperemia.

    (C) autoregulation.

    (D) reactive hyperemia.

    (E) hormonally regulated extrinsic control.

14. Intravenous infusion of vasopressin will result in

    (A) decreased mean arterial pressure

    (B) increased cardiac contractility.

    (C) decreased venoconstriction.

    (D) decreased unstressed volume.

    (E) decreased arteriolar constriction

15. An increase in cardiac contractility means

    (A) subsequent ventricular contractions will generate increased force until contractility is reduced.

    (B) maximum contractile force generated at a fixed ventricular end diastolic volume (EDV) will be increased.

    (C) maximum contractile force generated at any ventricular end systolic volume (ESV) will be increased

    (D) stroke work will increase.

    (E) all of the above.

16. If mean arterial pressure increases from 100 to 110 mm Hg,

    (A) venoconstriction increases.

    (B) total peripheral resistance increases.

    (C) blood levels of renin decrease.

    (D) coronary blood flow decreases.

    (E) carotid body chemoreceptors increase their firing rate.

17. Increased intracranial pressure above normal will result in

    (A) increased firing rate of arteriolar sympathetic efferent fibers.

    (B) decreased mean arterial pressure.

    (C) decreased firing rate of carotid baroreceptors

    (D) increased renal blood flow.

    (E). decreased mean circulatory filling pressure.

18. When an increase in ventricular end systolic pressure is associated with a decrease in ventricular end systolic volume (ESV), which of the following has increased:

    (A) ventricular end diastolic volume.

    (B) mean arterial pressure.

    (C) total peripheral resistance.

    (D) myocardial contractility.

    (E) firing of the cardiac parasympathetic nerves

19. An increase in cardiac afterload occurs when which of the following is increased:

    (A) stroke volume.

    (B) ventricular end diastolic pressure.

    (C) mean arterial pressure.

    (D) mean circulatory filling pressure.

    (E) pressure difference across the total peripheral resistance

DIRECTIONS: Each group of questions below consists of a number of lettered headings or a diagram or table with a number of lettered components, followed by a list of numbered words, phrases or statements. For each numbered word, phrase or statement, select the one lettered component that is most closely associated with it. Each lettered heading or lettered component may be selected once, more than once , or not at all.

20. _____ Start of 2nd Heart Sound
    
    
21. _____ Aortic Diastolic Pressure
    
    
22. _____ Start of Reduced Ventricular Ejection Phase