Conducting Stress Test Interpretation | Skills Pool
技能档案
Conducting Stress Test Interpretation
Interprets exercise and pharmacologic stress tests with Duke treadmill score and nuclear findings. Use when reading stress tests, interpreting nuclear perfusion, or documenting exercise tolerance.
Interprets exercise and pharmacologic stress tests with Duke treadmill score and nuclear findings.
Why This Skill Exists
Cardiac stress testing is the most widely used non-invasive method for evaluating suspected coronary artery disease, with over 10 million tests performed annually in the US. The choice of stress modality (exercise vs. pharmacologic) and imaging (ECG alone, echo, nuclear, CMR) must be matched to the clinical question and pretest probability. Misinterpretation — a false-negative treadmill ECG in a patient with LBBB, or failure to recognize balanced ischemia on perfusion imaging — can result in missed high-risk disease.
The Duke Treadmill Score (DTS) provides validated risk stratification for exercise ECG, and ACC Appropriate Use Criteria define when imaging should be added. This skill enforces systematic interpretation aligned with these evidence-based frameworks.
Checkpoint A: Pre-Draft Intake (Mandatory)
What was the clinical indication — chest pain evaluation, preoperative risk, post-revascularization assessment, arrhythmia evaluation? (default: "Chest pain / CAD evaluation")
What stress modality was used — treadmill exercise, pharmacologic (regadenoson, adenosine, dipyridamole, dobutamine)? (default: "Treadmill exercise")
相关技能
What imaging was used — ECG only, echocardiography, SPECT MPI, PET MPI, or CMR? (default: "ECG only")
Can the patient exercise adequately (≥ 85% MPHR)? (default: "Exercise capacity unknown")
Is the baseline ECG interpretable for ischemia (no LBBB, no LVH with repolarization abnormality, no digoxin, no paced rhythm, no WPW)? (default: "Baseline ECG interpretability not assessed")
What is the pretest probability of CAD? (default: "Intermediate — to be calculated")
Is there a prior stress test for comparison? (default: "No prior study available")
What medications is the patient taking (beta-blockers, CCBs, nitrates, caffeine)? (default: "Not provided")
Documents to Request
Complete stress test report with images/tracings
Pre- and post-stress ECGs (all stages)
Perfusion images (stress and rest) if nuclear study
Wall motion images at rest and stress if echo or CMR
Bruce protocol or specific treadmill protocol used
BP and HR data at each stage
Prior stress test for comparison
Recent ECG for baseline interpretation
Current medication list (beta-blocker held or continued)
Step 1: Exercise Parameters and Adequacy Assessment
Exercise Adequacy Criteria:
Target heart rate: ≥ 85% of age-predicted maximum (220 − age)
Submaximal test (< 85% MPHR) has significantly lower sensitivity — document and note limitation
If pharmacologic stress: confirm appropriate agent delivery and hemodynamic response
Exercise Capacity Assessment:
METs Achieved
Functional Capacity
Prognostic Implication
≥ 10
Excellent
Low risk regardless of other findings
7–9
Good
Favorable prognosis
5–6
Moderate
Intermediate risk
< 5
Poor
High risk; associated with increased mortality
Bruce Protocol Stages:
Stage
Speed (mph)
Grade (%)
Approximate METs
1
1.7
10
4.6
2
2.5
12
7.0
3
3.4
14
10.1
4
4.2
16
12.9
5
5.0
18
15.0
Reasons for Test Termination (document which applies):
Target HR achieved
Maximal exertion (patient request, fatigue)
Significant ST depression (≥ 2 mm horizontal/downsloping)
Sustained VT or symptomatic arrhythmia
Drop in SBP > 10 mmHg from baseline with ischemic signs
Severe hypertensive response (SBP > 250, DBP > 115)
Moderate-to-severe angina
Step 2: ECG Interpretation During Stress
Positive ECG Criteria for Ischemia:
≥ 1 mm horizontal or downsloping ST depression at 60–80 ms after J point
≥ 1 mm ST elevation in leads without pathologic Q waves (transmural ischemia)
ST depression in ≥ 5 leads and/or persisting > 5 minutes into recovery suggests severe/multivessel disease
False-Positive Causes (reduced specificity):
Baseline ST abnormalities (LVH, digoxin effect, LBBB)
Risk category and recommendation (medical management, additional imaging, catheterization)
Comparison with prior study
Checkpoint B: Post-Draft Alignment (Mandatory)
Was exercise adequacy (% MPHR and METs) documented?
Were ECG changes described with timing, leads, and morphology?
Was the Duke Treadmill Score calculated for exercise ECG tests?
Were imaging findings mapped to specific coronary territories?
Does the final recommendation align with the risk stratification?
Quality Audit
Clinical indication documented
Protocol and stress modality specified
Exercise duration and METs achieved reported
Peak HR and percentage of MPHR calculated
BP response documented at rest, peak, and recovery
Reason for test termination stated
ECG changes described with quantitative ST deviation
Duke Treadmill Score calculated (exercise ECG tests)
Perfusion defects described by location, severity, and reversibility (nuclear)
Wall motion analysis compared rest vs. stress (echo)
High-risk features explicitly assessed (TID, multi-territory ischemia, EF drop)
Medications held or continued noted (beta-blockers, caffeine)
Risk category assigned with next-step recommendation
Prior study comparison documented or absence noted
Appropriate use criteria met for the chosen modality
Guidelines
Exercise ECG alone (no imaging) is appropriate only when the baseline ECG is interpretable for ischemia and the patient can exercise adequately. If LBBB, LVH with repolarization changes, paced rhythm, WPW, or digoxin effect is present, imaging must be added.
Beta-blockers should be held for 24–48 hours before a diagnostic stress test for ischemia evaluation, unless clinically unsafe to discontinue.
Caffeine must be held for 12–24 hours before vasodilator stress (regadenoson, adenosine, dipyridamole) — it competitively antagonizes the pharmacologic effect.
A normal stress test at peak exercise (≥ 85% MPHR, ≥ 10 METs, no ECG changes) has > 99% negative predictive value for adverse cardiac events at 1 year.
The Duke Treadmill Score should be calculated for every exercise ECG test — it provides incremental prognostic information beyond ST changes alone.
Fixed defects on nuclear imaging should be correlated with clinical history and wall motion — some fixed defects represent hibernating myocardium amenable to revascularization (assess viability).
When stress test results are discordant with clinical suspicion, document the discrepancy and recommend additional testing (e.g., coronary CT angiography or catheterization).