Cardiac Vascular Nursing Exam Cardiac Vascular Nursing Exam Diagnostic Testing & Interpretation 1 — Questions and Answers
Question 1: On a 12-lead ECG, which finding is diagnostic of left bundle branch block (LBBB) that alters management of chest pain?
- Wide QRS >120ms with broad monophasic R wave in V5-V6 and rS pattern in V1 (Correct answer)
- Narrow QRS with ST elevation in inferior leads only
- Prolonged PR interval >200ms with normal QRS morphology
- Right axis deviation with RSR' pattern in V1 and wide S wave in V6
Correct answer: Wide QRS >120ms with broad monophasic R wave in V5-V6 and rS pattern in V1
New LBBB in the context of chest pain may represent STEMI equivalent, as LBBB's wide QRS with its characteristic morphology (broad R in V5-V6, rS in V1) obscures normal ST analysis.
Question 2: Which echocardiographic measurement is used to diagnose systolic heart failure and guide therapy initiation?
- Left ventricular ejection fraction (LVEF) less than 40% diagnoses HFrEF (Correct answer)
- Left ventricular end-diastolic volume greater than 150 mL
- E/A ratio less than 1.0 indicating diastolic dysfunction
- Tricuspid annular plane systolic excursion (TAPSE) less than 17mm
Correct answer: Left ventricular ejection fraction (LVEF) less than 40% diagnoses HFrEF
LVEF <40% defines HFrEF and triggers guideline-directed medical therapy with beta-blockers, ACE inhibitors/ARBs, and aldosterone antagonists that have proven mortality benefit.
Question 3: A troponin I level is drawn at presentation for chest pain, and a repeat level is ordered 3 hours later. What is the clinical purpose of serial troponin measurement?
- To detect the rise and fall pattern consistent with myocardial injury when initial values may be negative in early infarction (Correct answer)
- To monitor response to antiplatelet therapy during ACS treatment
- Serial troponin is only needed if the initial value is above the normal reference range
- To determine the exact size of the myocardial infarction in square centimeters
Correct answer: To detect the rise and fall pattern consistent with myocardial injury when initial values may be negative in early infarction
Troponin rises over 3–6 hours after myocardial injury; a significant delta (≥20% rise) between serial values confirms acute MI even when the initial value was within normal limits.
Question 4: During cardiac catheterization, a hemodynamic finding of elevated pulmonary capillary wedge pressure (PCWP >18 mmHg) indicates which condition?
- Left heart failure with elevated left atrial filling pressures (Correct answer)
- Right ventricular failure with normal left heart pressures
- Hypovolemia requiring fluid administration
- Pulmonary arterial hypertension from primary lung disease
Correct answer: Left heart failure with elevated left atrial filling pressures
PCWP reflects left atrial pressure; elevation above 18 mmHg indicates left ventricular dysfunction or mitral valve disease causing increased left-sided filling pressures.
Question 5: Which finding on an ankle-brachial index (ABI) test is diagnostic of significant peripheral arterial disease?
- ABI less than 0.90 (Correct answer)
- ABI of 1.0 to 1.3
- ABI greater than 1.4 with non-compressible vessels
- ABI of 0.91 to 1.0 indicating borderline normal
Correct answer: ABI less than 0.90
An ABI <0.90 indicates significant arterial stenosis in the lower extremity; the lower the ABI, the more severe the PAD, with values <0.40 representing critical limb ischemia.
Question 6: What does an elevated B-type natriuretic peptide (BNP) level primarily indicate in a dyspneic patient?
- Ventricular wall stress from elevated filling pressures, supporting a diagnosis of heart failure (Correct answer)
- Acute pulmonary embolism as the primary cause of dyspnea
- Pneumonia with systemic inflammatory response
- Asthma exacerbation with hyperinflation
Correct answer: Ventricular wall stress from elevated filling pressures, supporting a diagnosis of heart failure
BNP is released by ventricular myocytes in response to increased wall stretch from elevated filling pressures; elevated levels support heart failure as the cause of dyspnea with high sensitivity.
Cardiac Vascular Nursing Exam Cardiac Vascular Nursing Exam Diagnostic Testing & Interpretation 1
On a 12-lead ECG, which finding is diagnostic of left bundle branch block (LBBB) that alters management of chest pain?