What is the recommended format for typing a results letter for an exercise stress test with no electrocardiogram (EKG) evidence of ischemia?

Exercise Stress Test Results Letter Format

A results letter for an exercise stress test with no EKG evidence of ischemia should include: patient demographics, indication for testing, exercise protocol and workload achieved, hemodynamic response, symptoms during testing, EKG findings (specifically stating no ischemic changes), reason for test termination, and a clear interpretation statement. 1

Essential Components to Include

Patient Information and Test Details

• Patient demographics: Name, date of birth, medical record number 2
• Date of test and indication: Document the clinical reason for ordering the test (e.g., chest pain evaluation, pre-operative risk assessment, known CAD follow-up) 3, 2
• Exercise protocol used: Specify the protocol (e.g., Bruce, modified Bruce) as this affects interpretation 1, 2

Exercise Performance Metrics

• Workload achieved: Express in METs (metabolic equivalents), exercise stage reached, or Watts 1
• Exercise duration: Total time exercised 2
• Peak heart rate achieved: Include both absolute value and percentage of age-predicted maximum heart rate 1
• Blood pressure response: Baseline, peak exercise, and recovery values 1
• Functional capacity assessment: Compare achieved METs to predicted values for age and sex 1, 4

Clinical Response During Testing

• Symptoms: Document presence or absence of chest pain, dyspnea, dizziness, leg fatigue, or other discomfort 1, 2
• Reason for test termination: State whether test was symptom-limited (maximal) or submaximal, and the specific reason for stopping (e.g., target heart rate achieved, fatigue, leg discomfort) 1, 2

EKG Findings - The Critical Section

• Baseline EKG: Note if interpretable for ischemia or if baseline abnormalities present 1, 3
• ST-segment analysis: Explicitly state "No evidence of ischemia" and define this as: no horizontal or downsloping ST-segment depression ≥1 mm at 60-80 ms after the J-point, no ST-segment elevation ≥2 mm 1
• Arrhythmias: Document presence or absence of ventricular ectopy, atrial fibrillation, or other rhythm disturbances 1
• Heart rate recovery: Include the decrease in heart rate at 1 minute of recovery (abnormal if ≤12 bpm) 1

Risk Stratification Elements

• Duke Treadmill Score: Calculate and report this validated prognostic tool when applicable (exercise time - [5 × ST deviation] - [4 × angina index]) 1, 5
• Exercise capacity as prognostic marker: Note that achieving >10 METs generally indicates low risk and excellent prognosis 4, 5

Interpretation Statement Format

For a negative test, the interpretation should clearly state:

"Negative exercise stress test for inducible myocardial ischemia." 1

Follow this with supporting details:

• Patient achieved [X] METs, which is [percentage] of predicted functional capacity 4
• No anginal symptoms developed during exercise 1
• No significant ST-segment changes suggestive of ischemia 1
• Hemodynamic response was appropriate/normal 1

Common Pitfalls to Avoid

• Submaximal testing: If the patient failed to achieve ≥85% of age-predicted maximum heart rate, note this as a limitation and consider the test "indeterminate" rather than definitively negative 1, 3
• Baseline EKG abnormalities: If resting ST-segment depression ≥0.10 mV, complete LBBB, pre-excitation, LV hypertrophy, digoxin use, or paced rhythm were present, the EKG is not interpretable for ischemia and this should be explicitly stated 1, 3
• Inadequate exercise capacity: If the patient achieved <5 METs, the test may not have adequately stressed the cardiovascular system 1, 4
• Failure to document functional capacity: Exercise capacity alone is one of the strongest predictors of mortality and must be included 4

Clinical Context Considerations

When the test is truly negative (adequate exercise, no symptoms, no EKG changes), state the clinical implications:

• Low probability of significant obstructive coronary artery disease 1, 6
• Good functional capacity suggests favorable prognosis 4, 5
• However, note that a negative test does not completely exclude CAD, particularly in high pre-test probability patients 6

Recent evidence challenges the concept of "false positive" tests: In patients with angina and nonobstructive coronary arteries, positive EKG changes may reflect coronary microvascular dysfunction rather than being truly false positive 7. Therefore, when reporting a negative test, you are documenting absence of both epicardial and microvascular ischemia.