Free CMC (Adult) Exam Practice Questions

Sample Practice Questions

Try these 10 sample questions from the CMC (Adult) Exam practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1An adult with lung cancer develops hypotension and rising jugular venous pressure as a pericardial effusion enlarges. The team diagnoses cardiac tamponade. Which mechanism primarily explains the falling cardiac output?

   1. A.Loss of circulating blood volume from external hemorrhage
   2. B.Reduced ventricular filling from increased pericardial pressureCorrect answer: B
   3. C.Reduced systemic vascular resistance from generalized vasodilation
   4. D.Reduced myocardial contraction from extensive ventricular infarction

   Explanation: The NCI lists "Progressive decrease in cardiac diastolic filling." among the effects of pericardial tamponade. Compression by the accumulating fluid restricts filling, reducing stroke volume and cardiac output. Hemorrhagic volume loss, systemic vasodilation and primary myocardial infarction describe different shock mechanisms.

   Reference: NCI Cardiopulmonary Syndromes PDQ — Malignant Pericardial Effusion, Etiology and Pathophysiology

2. 2An adult with a large acute pulmonary embolus develops hypotension and a dilated, poorly contracting right ventricle. Which immediate hemodynamic change caused the right ventricular strain?

   1. A.Reduced systemic vascular resistance
   2. B.Reduced pulmonary venous pressure
   3. C.Increased left ventricular compliance
   4. D.Increased pulmonary vascular resistanceCorrect answer: D

   Explanation: Mechanical obstruction and vasoconstriction acutely increase right ventricular afterload, potentially causing RV failure and shock. The source states, "Increase in pulmonary vascular resistance caused by mechanical obstruction and vasoconstriction resulting in tachycardia and hypotension"

   Reference: Merck Manual Professional: Pulmonary Embolism — Pathophysiology

3. 3During right heart catheterization from an internal jugular vein, which sequence does the catheter follow before entering the pulmonary artery?

   1. A.Right atrium, mitral valve, left ventricle, aortic valve
   2. B.Right ventricle, tricuspid valve, right atrium, pulmonary valve
   3. C.Right atrium, tricuspid valve, right ventricle, pulmonary valveCorrect answer: C
   4. D.Left atrium, mitral valve, left ventricle, pulmonary valve

   Explanation: The venous catheter advances through the right-sided chambers and their valves; it does not cross the mitral or aortic valve. The source states, "A catheter is passed into the right atrium, through the tricuspid valve, into the right ventricle, and across the pulmonary valve into the pulmonary artery."

   Reference: Merck Manual Professional: Cardiac Catheterization — Procedure, Right heart catheterization

4. 4An adult's measured cardiac output is 4.0 L/min and body surface area is 2.0 m². What is the cardiac index?

   1. A.8.0 L/min/m²
   2. B.4.0 L/min/m²
   3. C.2.0 L/min/m²Correct answer: C
   4. D.0.5 L/min/m²

   Explanation: CI = CO/BSA = 4.0/2.0 = 2.0 L/min/m². Multiplication yields 8.0, omitting indexing yields 4.0, and reversing the division yields 0.5. The source states, "CI = CO/BSA"

   Reference: Merck Manual Professional: Cardiac Catheterization — Measurement of cardiac output and flow

5. 5A patient with a malignant pericardial effusion becomes tachycardic and hypotensive. Which echocardiographic finding would most strongly support tamponade physiology?

   1. A.Posterior mitral leaflet displacement during ventricular systole
   2. B.Regional left ventricular akinesis during ventricular systole
   3. C.Right ventricular free-wall collapse during ventricular diastoleCorrect answer: C
   4. D.Asymmetric interventricular septal thickening throughout the cycle

   Explanation: The NCI identifies "right ventricular or atrial diastolic collapse" as an echocardiographic finding associated with suspected pericardial tamponade. In this clinical setting, right ventricular diastolic collapse supports compression by pericardial pressure. Leaflet prolapse, regional akinesis and septal hypertrophy do not demonstrate that filling-pressure relationship.

   Reference: NCI Cardiopulmonary Syndromes PDQ — Malignant Pericardial Effusion, Diagnosis

6. 6A stable adult has a high clinical suspicion for acute pulmonary embolism. Kidney function is adequate and there is no iodinated contrast contraindication. Which imaging study is commonly used to establish the diagnosis?

   1. A.CT pulmonary angiographyCorrect answer: A
   2. B.Noncontrast chest CT
   3. C.Coronary calcium scoring CT
   4. D.Carotid CT angiography

   Explanation: CT pulmonary angiography evaluates the pulmonary arterial circulation for emboli; the other CT studies address different structures or lack the required contrast evaluation. The source states, "Diagnosis of pulmonary embolism is most commonly accomplished with CT angiography"

   Reference: Merck Manual Professional: Pulmonary Embolism — Opening definition

7. 7A properly obtained pulmonary artery occlusion pressure is used in an adult without conditions that invalidate the estimate. Which pressure does it generally approximate?

   1. A.Aortic systolic pressure
   2. B.Right ventricular systolic pressure
   3. C.Systemic arterial mean pressure
   4. D.Left atrial pressureCorrect answer: D

   Explanation: PAOP, or wedge pressure, generally reflects left-sided filling pressure rather than a systemic arterial or right ventricular systolic pressure. The source states, "PAOP (also called pulmonary capillary wedge pressure) approximates left atrial and left ventricular end-diastolic pressure in most cases."

   Reference: Merck Manual Professional: Cardiac Catheterization — Procedure, Right heart catheterization

8. 8A pulmonary artery catheter system calculates cardiac output after a saline bolus by analyzing the resulting blood temperature change. Which method is being used?

   1. A.Fick oxygen-consumption method
   2. B.Doppler echocardiographic method
   3. C.Dye-dilution method
   4. D.Thermodilution methodCorrect answer: D

   Explanation: Thermodilution uses the temperature change after an injectate bolus. Fick uses oxygen consumption and extraction; Doppler uses flow measurements; dye dilution uses an indicator-concentration curve. The source states, "TB – TI is the difference between body and injectate temperatures; injectate is usually dextrose or saline."

   Reference: Merck Manual Professional: Cardiac Catheterization — Cardiac Output Equations, Thermodilution technique

9. 9While monitoring a patient with a large pericardial effusion, a nurse observes that P-wave and QRS amplitudes vary in successive beats despite a regular underlying rhythm. What is the name of this finding?

   1. A.Electrical alternansCorrect answer: A
   2. B.Ventricular bigeminy
   3. C.Wandering atrial pacemaker
   4. D.Second-degree atrioventricular block

   Explanation: The NCI describes "variation in the amplitude of the P wave and QRS complex in successive beats on ECG, referred to as electrical alternans." This is amplitude variation rather than premature ventricular beats, shifting atrial pacemakers or failure of atrioventricular conduction.

   Reference: NCI Cardiopulmonary Syndromes PDQ — Malignant Pericardial Effusion, Diagnosis, electrocardiography

10. 10A patient has acute pulmonary embolism but anticoagulation is temporarily contraindicated by active major bleeding. Which measure may be considered until anticoagulation can resume?

    1. A.An intravenous unfractionated heparin infusion
    2. B.An inferior vena caval filterCorrect answer: B
    3. C.A subcutaneous low-molecular-weight heparin regimen
    4. D.A systemic fibrinolytic drug infusion

    Explanation: A caval filter can intercept emboli from the lower venous circulation during a temporary anticoagulation contraindication. It does not replace anticoagulation once treatment becomes safe. The source states, "When anticoagulation is contraindicated, an inferior vena caval (IVC) filter can be considered until anticoagulation is resumed."

    Reference: Merck Manual Professional: Pulmonary Embolism — Opening definition