NBE Stress Echocardiography 4 — Questions and Answers
Question 1: What is the role of atropine in dobutamine stress echocardiography?
- To reduce myocardial oxygen demand
- To augment heart rate when target heart rate is not achieved with maximum dobutamine (Correct answer)
- To reverse dobutamine-induced hypertension
- To prevent dobutamine-induced arrhythmias
Correct answer: To augment heart rate when target heart rate is not achieved with maximum dobutamine
Atropine (0.25–1.0 mg in divided doses) is added when the target heart rate is not reached at maximum dobutamine, as it enhances chronotropic response via vagal blockade.
Question 2: A patient with left bundle branch block (LBBB) undergoes stress echocardiography. Which stress modality is preferred?
- Treadmill exercise stress echo
- Dobutamine stress echocardiography
- Vasodilator (adenosine/dipyridamole) stress echocardiography (Correct answer)
- Bicycle ergometer exercise stress echo
Correct answer: Vasodilator (adenosine/dipyridamole) stress echocardiography
Vasodilator stress is preferred in LBBB because exercise and dobutamine can cause septal wall motion abnormalities unrelated to coronary disease due to rate-dependent LBBB-induced septal dysynchrony.
Question 3: During stress echocardiography, which segment classification system divides the left ventricle into 17 segments?
- AHA 16-segment model with addition of the true apex (Correct answer)
- ASE 12-segment model with basal additions
- ESC 20-segment model
- Modified 14-segment AHA model
Correct answer: AHA 16-segment model with addition of the true apex
The ASE/AHA 17-segment model adds the true apical cap (segment 17) to the 16-segment model to account for the non-visualizable apex tip.
Question 4: What defines a 'dyskinetic' wall motion pattern in echocardiographic scoring?
- Reduced but present inward wall motion
- Absence of inward wall motion
- Paradoxical outward motion during systole (Correct answer)
- Exaggerated inward motion greater than normal
Correct answer: Paradoxical outward motion during systole
Dyskinesis is defined as paradoxical outward motion of the myocardial wall during systole, assigned a wall motion score of 4.
Question 5: Which finding during stress echocardiography is most consistent with severe multivessel coronary artery disease?
- Single-territory wall motion abnormality at high-dose dobutamine
- Normal resting wall motion with isolated apical ischemia at peak stress
- Diffuse global hypokinesis developing at low workload involving multiple territories (Correct answer)
- Isolated inferior wall hypokinesis at peak dobutamine dose
Correct answer: Diffuse global hypokinesis developing at low workload involving multiple territories
Diffuse, multi-territory wall motion abnormalities developing at low workload suggest extensive ischemia consistent with severe multivessel or left main coronary artery disease.
Question 6: In stress echocardiography for valvular heart disease evaluation, which condition most benefits from exercise stress echo to guide management?
- Severe symptomatic mitral regurgitation
- Asymptomatic severe aortic stenosis (Correct answer)
- Mild tricuspid regurgitation
- Moderate pulmonic stenosis
Correct answer: Asymptomatic severe aortic stenosis
Exercise stress echo in asymptomatic severe aortic stenosis can unmask symptoms or hemodynamic compromise, helping determine optimal timing for valve intervention.
Question 7: What is the significance of a post-exercise pulmonary artery systolic pressure (PASP) greater than 60 mmHg on stress echocardiography?
- Normal physiological response to exercise
- Mild pulmonary hypertension without clinical significance
- Abnormal elevation suggesting significant pulmonary hypertension or diastolic dysfunction (Correct answer)
- Indicates right ventricular outflow tract obstruction
Correct answer: Abnormal elevation suggesting significant pulmonary hypertension or diastolic dysfunction
A peak exercise PASP >60 mmHg is abnormal and may indicate exercise-induced pulmonary hypertension, often related to elevated left-sided filling pressures or underlying pulmonary vascular disease.
NBE Stress Echocardiography 4
What is the role of atropine in dobutamine stress echocardiography?