Bio-Med 281

Cardiac Pathophysiology

Final Examination

September 25, 2000
 
 

ª ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª
 
 

I cannot teach anybody anything, I can only make them think. -- Socrates
 
 

Murphy's Law of Copiers: The legibility of a copy is inversely proportional to its importance.
 
 

Murphy’s Rule of Accuracy: When working toward the solution of a problem, it always helps if you know the answer.
 
 

ª ªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªªª
 
 

The roots of education are bitter, but the fruit is sweet. -- Aristotle
 

It ain’t over ‘till it’s over. – Yogi Berra
 
 

ª ªªª







Questions 1 – 5: A thirty-five year old male Egyptian immigrant presents to the medical clinic for a pre-employment physical. He states that he had no prior illnesses but has been having some dyspnea on climbing stairs recently. On physical examination, his main finding is that of a loud first heart sound, a high-pitched sound immediately after S2, and a low-pitched diastolic murmur during diastole.

  1. This patient is likely to have all of the following anatomical or physiological findings, except:
  1. a normal left ventricle
  2. a dilated left atrium
  3. thinned and elongated chordae tendinae
  4. doming of the mitral valve leaflets
  5. mildly elevated pulmonary artery pressures

    6.  

     
     
     
     
     

    2.  The most likely etiology (cause) of this patient’s abnormality is:

    1. prior acute rheumatic fever
    2. longstanding hypertension
    3. acute "silent" myocardial infarction
    4. congenital bicuspid aortic valve
    5. bacterial endocarditis

      6.  

       
       
       

      3.  The predominant physiological abnormality in this patient is:

      1. impaired emptying of the left ventricle
      2. impaired filling of the left ventricle
      3. volume overload of the left ventricle
      4. pressure overload of the left ventricle
      5. diastolic left ventricular dysfunction
Several months after this patient has started his job as an accountant, he develops dyspnea while working on tax returns on April 14th. He presents to the employee health department where his heart rate is noted to be rapid. He is sent to your office where an EKG rhythm strip reveals the following rhythm:

4.  Identify the abnormal rhythm:

    1. sinus tachycardia
    2. atrial fibrillation
    3. atrial flutter
    4. ventricular fibrillation
    5. ventricular tachycardia

      6.  

       
       
       

      5.  The pathophysiological mechanism of this arrhythmia is most likely:

      1. increased automaticity in the atrium
      2. increased automaticity in the A-V node
      3. increased conduction through the A-V node
      4. re-entry within the A-V node
      5. re-entry within the atrium
Questions 6 –7: A 75 year-old female has been under treatment for arthritis with four weeks of non-steroidal anti-inflammatory drugs. She now notes two days of increasing chest pressure with exertion and black, tarry stools. On examination she appears pale and her vital signs are: Pulse 110/min; BP: 90/60; Resp: 16; Temp: 98.6 F.

6.  Pathophysiologic mechanisms for her accelerated angina pectoris might include all of the following, except:

    1. Increased myocardial oxygen demand due to sinus tachycardia
    2. Increased left ventricular wall tension due to increased preload
    3. Increased myocardial contractility due to increased sympathetic tone
    4. Decreased diastolic coronary perfusion pressure due to hypotension
    5. Decreased oxygen carrying capacity due to anemia

      6.  

       
       
       

      7.  During episodes of chest pressure, all of the following pathophysiologic mechanisms may be taking place, except:

      1. increased local adenosine levels, causing local vasodilation (to increase coronary blood flow)
      2. increased local EDRF or nitric oxide levels, causing local vasodilation (to increase coronary blood flow)
      3. increased catecholamine production, causing increase in heart rate and contractility (increasing myocardial oxygen demand)
      4. increased external compression of the coronary vessels, causing increased coronary vascular resistance
      5. increased local cyclic-AMP levels, causing local vasoconstriction (decreasing coronary blood flow)
Questions 8 – 13: A 4 year old boy is seen in the office with parental complaints of inability to play with other children for any length of time before tiring out. On exam his cheeks appear ruddy with deep red lips. There is a loud, harsh systolic ejection murmur. The patient has mild clubbing of the fingers and the EKG demonstrates right ventricular hypertrophy.

8. The most likely diagnosis is:

    1. ASD
    2. VSD
    3. transposition of the great arteries
    4. tetralogy of Fallot
    5. coarctation of the aorta
9 - 13: TRUE or FALSE: A chest X-ray examination of this boy would likely show which of the following (more than one may be correct):
  1. pulmonary oligemia
  2. cardiomegaly
  3. lobar infiltrates
  4. boot shaped heart
  5. pulmonary edema
Questions 14 - 18: Match each question with the single best answer (A - E).
 
14.

Decreased diastolic aortic pressure;

increased left ventricular end-diastolic pressure;

volume overload of the left ventricle;

bounding peripheral pulses
A

Constrictive Pericarditis
15.

Impaired diastolic filling of ventricles;

jugular venous pressure with rapid "y descent";

left ventricular diastolic pressure tracing with "dip and plateau" configuration
B

Restrictive Cardiomyopathy
16.

Impaired diastolic filling of ventricles; 

cyclical decrease in systolic blood pressure during inspiration;

elevated jugular venous pressure without Kussmaul’s sign
C

Aortic Regurgitation
17.

Impaired diastolic filling of the left ventricle; normal left ventricular end-diastolic pressure;

increased pulmonary venous pressure with occasional "reactive" pulmonary hypertension
D

Cardiac Tamponade
18. 

Impaired diastolic filling of the ventricles; fibrosis, scarring, or infiltration of the myocardium; normal pericardial tissue
E

Mitral Stenosis
     
    19.  The action potential of a pacemaker cell differs from that of a cardiac myocyte in all of the following ways except:
A. phase 0 is due to slow Ca++ influx

B. maximum negative voltage is less negative (-60 mV)

C. the resting membrane potential is determined by voltage sensitive ion channels

D. spontaneous depolarization occurs during phase 4

20.  A 28 year-old woman presents with shortness of breath. Physical examination reveals a grade II/VI diastolic murmur heard at the apex with pre-systolic accentuation. Her EKG reveals a biphasic P wave in lead V1. The terminal negative deflection of the P wave is 1mm wide by 1mm deep. The diagnosis based on her P wave morphology is:

A. right atrial enlargement

B. left atrial enlargement

C. atrial flutter

D. left ventricular hypertrophy

21.  Re-entry is the principle mechanism of arrhythmogenesis for all of the following arrhythmias, except:

 A. supraventricular tachycardia

B. atrial flutter

C. ventricular tachycardia

D.  atrial fibrillation

E.  torsades de pointes

22.  The following are all true about a re-entrant circuit except:

 A. it is a self-sustaining electrical circuit

B. requires unidirectional block in one limb of the circuit

C. requires rapid conduction through one limb of the circuit

D. can occur in the AV node

E.  can occur in the left ventricle

23.  A 58 year-old man with an ischemic cardiomyopathy presents to the emergency room complaining of palpitations and dizziness. His heart rate is 160 beats/min. On EKG, the QRS complexes are regular, wide and bizarre. The P waves are visible but do not appear to have any relationship to the QRS complexes. This patient’s rhythm is most likely:
          A. ventricular fibrillation

          B. ventricular tachycardia

          C. atrial fibrillation

          D. sinus tachycardia

          24.  Left ventricular compliance is reduced in all of the following conditions, except:

          1. Mitral stenosis
          2. Aortic stenosis
          3. Acute myocardial infarction
          4. Restrictive cardiomyopathy
          5. Dilated cardiomyopathy
Questions 25 – 31: A 55 year old male presents to the emergency room with 2 hours of severe substernal chest pressure radiating to his left arm, associated with dyspnea and diaphoresis. On EKG, he is noted to have ST segment elevations in the precordial leads V1 to V5. 25. Pathophysiologic mechanisms for this patient’s syndrome are likely to include all of the following, except:
    1. coronary embolism from the left atrium or left ventricle
    2. intracoronary plaque rupture or fissuring
    3. platelet aggregation on the plaque
    4. intracoronary thrombus formation
    5. local coronary vasospasm

      6.  

       
       
       
       
       

      57.  Complications of the patient’s syndrome over the next week might include any of the following, except:

    1. rupture of the free wall of the left ventricle, resulting in cardiac tamponade
    2. ventricular tachycardia, leading to hypotension or ventricular fibrillation
    3. congestive heart failure, due to decreased compliance and decreased cardiac output of the left ventricle
    4. rupture of the postero-medial papillary muscle of the left ventricle, resulting in acute mitral regurgitation
    5. rupture of the intra-ventricular septum, resulting in an acute ventricular septal defect
This patient’s Frank Starling curve is represented below as the lower of the two curves.

Please answer the next TRUE or FALSE questions based on this diagram (A = TRUE ; B = FALSE).

26. This patient’s prognosis is better if he is on point A rather than point B on the curve.

27. This patient can be moved from point B to point C by administering fluids.

28. This patient can be moved from point A to point B by administering a positive inotrope.

29. Patients falling into Quadrant IV have a mortality rate of less than 30 percent.

30. Patients falling into Quadrant III usually have clear lungs and low blood pressure.
 
 

Questions 31 – 33:

Please match each of the three labeled diagrams with their corresponding legends, by filling in A, B, or C.
 
 

31. These pressure-volume loops show the effect of increasing afterload on stroke volume.
 
 

32. These pressure-volume loops show the effect of increasing preload on stroke volume.
 
 

33. These pressure volume loops show the effect of adding an inotropic agent on stroke volume.
 
 

Questions 34 - 35: A 70 year-old woman with a known heart murmur and a history of atrial fibrillation has had progressive angina and dyspnea on exertion. On physical exam she has a harsh crescendo/decrescendo murmur at the left sternal border radiating to the right upper sternal border. She is referred for a cardiac catheterization, and her hemodynamics are noted below.


 
 

 34. Appropriate therapy would include all of the following except:

a. b - blockers

b. Ca 2+ -channel blockers

c. Disopyramide

d. Aortic valve replacement

e. Alcohol septal ablation

35.  This patient’s heart murmur would be expected to do all of the following, except:
      1. increase with standing up from a squatting position
      2. decrease with elevation of the legs while in a supine position
      3. decrease with the Valsalva maneuver
      4. increase after a premature ventricular contraction
      5. decrease during pregnancy (if she were younger)

36. All of the following are features of pericardial tamponade except:

a. electrical alternans on EKG

b. pulsus paradoxus

c. pulsus alternans

d. equalized diastolic pressures

e. blunted "y" descent

 37. A 55 year-old man presented with 2 weeks of increased shortness of breath, chest pain, lower extremity edema and abdominal bloating. On exam his BP was 80/60, his heart rate was 110 beats/min, and his jugular veins were elevated to the angle of his jaw. His respiratory rate was 36/minute. When palpating his pulse, it seemed to disappear with each inspiration. His CXR showed a markedly enlarged cardiac silhouette, but clear lung fields. Initial therapy should have included:
    1. Furosemide 40mg IV
    2. Sublingual Nitroglycerin
    3. Metoprolol 5 mg IV
    4. Normal saline 250 ml IV bolus
    5. Dobutamine IV

      6.  

       
       
       

      38.  True statements regarding the pathological time course in acute myocardial infarction include all the following, except:

      1. Yellow softening from resorption of dead tissue by macrophages generally occurs within 36 hours of the infarction
      2. Fibrosis and scarring generally occurs by two months after infarction
      3. Irreversible cellular injury usually occurs within 20-30 minutes of the onset of the infarction
      4. ATP levels fall and regional systolic function drops within one to two minutes of the onset of the infarction
      5. Coagulation necrosis generally occurs within 24 hours of the onset of infarction
Imaging questions 39 – 43: Match each method appropriately.
 
39.

Imaging technique most effective in determining precise anatomical coronary artery information 
A

Resting thallium nuclear image
40.

Imaging technique most useful in visualizing valvular and sub-valvular structures
B

Exercise and resting 
thallium nuclear imaging
41.

Imaging technique most useful in determining severity of valve stenoses non-invasively
C

2-D echocardiography
42. 

Imaging technique most useful in determining significance of coronary stenoses non-invasively
D

Doppler examination 
during 2-D 
echocardiography 
43.

Imaging technique most useful in determining myocardial viability non-invasively
E

Cardiac catheterization 
(coronary angiography)

 

44. Right ventricular infarction is associated with all of the following findings, except:

    1. Clear lung fields with jugular venous distension
    2. A left ventricular S3 gallop
    3. Hypotension responding to fluid administration
    4. Inferior wall myocardial infarction
    5. Elevated right atrial pressure, almost equal to PCW (wedge) pressure
45. Acute ventricular septal rupture occurring several days after myocardial infarction is associated with all of the following, except:
    1. Yellow softening in the area of the intraventricular septum
    2. Oxygen saturation "step-up" from the right atrium to the pulmonary artery
    3. A loud systolic and diastolic "to-and-fro" murmur at the left sternal border
    4. A systolic "thrill" which is palpable at the left sternal border
    5. Signs and symptoms of congestive heart failure
Questions 46 – 50: Match each term with the appropriate definition
 
46. {Pressure x Radius} / {2 x wall thickness}measured during systole
A

Preload
47. {Pressure x Radius} / {2 x wall thickness}measured during diastole
B

Afterload
48. {Pressure x Radius} / {2 x wall thickness}measured at any point in time
C

Wall tension
49. Change in pressure / Change in volume
D

Compliance
50. Change in volume / Change in pressure
E

Stiffness

51. The Fick Method of determining cardiac output predicts all of the following, except:

    1. An increase in mixed venous oxygen saturation suggests an increase in cardiac output
    2. A decrease in oxygen consumption suggests an increase in cardiac output
    3. The cardiac output can be estimated using three parameters: the oxygen consumption, the arterial oxygen saturation and the mixed venous oxygen saturation
    4. The calculation of the cardiac output using the Fick method is independent of the ability of the lungs to oxygenate the blood
52. Acute mitral regurgitation differs from chronic mitral regurgitation in all of the following ways, except:
    1. Acute mitral regurgitation (MR) results in large V-waves on the pulmonary capillary wedge tracing, while chronic mitral regurgitation does not
    2. Acute MR is more likely to present as acute pulmonary edema than chronic MR
    3. Acute MR often occurs due to an acute inferior MI, while chronic MR is usually due to other causes
    4. Acute MR causes a systolic ejection murmur, while chronic MR causes a holosystolic "plateau" murmur
    5. Acute MR is effectively treated with afterload reduction, while chronic MR is not
Questions 53 - 56: Match the following signs/symptoms with their etiology
 
53.

Bisfiriens pulse
A

CardiacTamponade
54.

Pulsus Alternans
B

Aortic Stenosis
55.

Pulsus paradoxus
C

Hypertrophic Cardiomyopathy
56.

Pulsus tardus et parvus
D

Dilated Cardiomyopathy

57.  See above (25 b)

Answers to 2000 EXAM