Interpretation and Management of Stress Test Results with Dyspnea and T-wave Abnormalities
The stress test results indicate a non-diagnostic test for ischemia with good functional capacity and no evidence of significant cardiac ischemia. The patient's dyspnea and T-wave abnormalities in V2 likely represent a non-cardiac cause of dyspnea that requires further pulmonary evaluation.
Analysis of Stress Test Results
Cardiovascular Performance
- Exercise capacity: Above predicted for age and sex (8.6 METs vs. 5.0 METs predicted)
- Test duration: 6 minutes and 56 seconds (reached stage 3 of Bruce protocol)
- Symptoms: Dyspnea present, but no angina
- Test termination: Patient request due to dyspnea
- Target heart rate: Not achieved (test considered non-diagnostic for ischemia)
ECG Findings
- Resting ECG: Normal sinus rhythm with T-wave abnormalities in V2
- Stress ECG: No ST-segment deviation
- Recovery ECG: No ST-segment deviation, rare PACs and PVCs
Clinical Significance
The patient's stress test demonstrates several important findings:
Good functional capacity: The patient achieved 8.6 METs, which is above predicted for age and sex. This is a strong positive prognostic indicator, as functional capacity is one of the most powerful predictors of cardiovascular outcomes 1.
Non-diagnostic for ischemia: While the test didn't reach 85% of maximal predicted heart rate, the absence of chest pain, good exercise capacity, and lack of ST-segment changes during exercise suggest a low likelihood of significant coronary artery disease 1.
T-wave abnormalities in V2: Isolated T-wave abnormalities in right precordial leads require careful evaluation. According to European Heart Journal guidelines, T-wave inversions ≥2 mm in two or more adjacent leads are rarely observed in healthy individuals and may represent underlying heart disease 1.
Dyspnea as primary symptom: Dyspnea without angina during stress testing often suggests non-cardiac or non-ischemic causes of symptoms 1.
Management Recommendations
Based on the stress test results, I recommend the following approach:
1. Pulmonary Evaluation
- Pulmonary function testing (PFTs) with diffusion capacity (DLCO) measurement
- Consider cardiopulmonary exercise testing (CPET) to better characterize the dyspnea
- If DLCO is abnormal, further gas exchange evaluation during exercise may be warranted 2
2. Cardiac Follow-up
- Echocardiography to evaluate:
- Left ventricular function
- Diastolic function (especially with exercise if initial testing is normal)
- Valvular function
- Pulmonary pressures
3. Risk Factor Management
- Optimize cardiovascular risk factors
- Consider stress echocardiography if symptoms persist or worsen despite normal initial findings
Interpretation of Key Findings
The T-wave abnormalities in V2 require careful consideration. According to guidelines, T-wave inversions may represent the only sign of inherited heart muscle disease even without other features 1. However, isolated T-wave abnormalities in right precordial leads can be a normal variant, especially in the absence of other concerning findings.
The presence of dyspnea without chest pain as the limiting symptom, combined with good exercise capacity, suggests that the dyspnea may be due to:
- Deconditioning
- Pulmonary disease
- Early heart failure with preserved ejection fraction
- Pulmonary vascular disease
Important Considerations
- The good functional capacity (8.6 METs) is reassuring and associated with excellent prognosis
- Dyspnea without chest pain during stress testing is less likely to be associated with myocardial ischemia 3
- The non-diagnostic nature of the test (not reaching target heart rate) should be acknowledged, but the absence of symptoms or ECG changes at a good workload is reassuring
- T-wave abnormalities should not be dismissed without appropriate follow-up, particularly if they are new or dynamic
This patient's presentation warrants a focused evaluation of non-cardiac causes of dyspnea while maintaining appropriate cardiac surveillance due to the T-wave abnormalities.