From the Guidelines
A positive stress test does not definitively indicate coronary artery disease (CAD), but rather suggests the possibility of CAD, and further diagnostic testing such as coronary angiography or CT coronary angiography may be necessary to confirm the diagnosis. While stress tests are valuable screening tools that detect reduced blood flow to the heart during exertion, they have limitations in both sensitivity and specificity. A positive result means there were abnormalities detected during the test, such as ECG changes, perfusion defects on imaging, or wall motion abnormalities, which could indicate restricted blood flow to heart muscle. However, false positives occur in about 15-20% of cases, particularly in women, individuals taking certain medications, or those with left ventricular hypertrophy 1.
Clinical Context and Next Steps
The clinical context matters significantly - a positive stress test in someone with chest pain and multiple cardiovascular risk factors is more concerning than in a low-risk individual. According to the 2014 ACC/AHA/AATS/PCNA/SCAI/STS focused update, coronary angiography may be considered in patients with stress test results of acceptable quality that do not suggest the presence of CAD when clinical suspicion of CAD remains high and there is a high likelihood that the findings will result in important changes to therapy 1.
Diagnostic Testing
Definitive diagnosis of CAD typically requires more specific testing such as coronary angiography or CT coronary angiography. The European Society of Cardiology guidelines recommend exercise ECG as the initial test for establishing a diagnosis of stable coronary artery disease (SCAD) in patients with symptoms of angina and intermediate pre-test probability of CAD, unless they cannot exercise or display ECG changes which make the ECG non-evaluable 1.
Limitations of Stress Tests
Stress tests have limitations, and a "normal" ECG stress test in patients taking anti-ischaemic drugs does not rule out significant coronary disease. In patients who are appropriately selected, coronary CTA is another option. Furthermore, exercise stress testing can also be useful to evaluate the efficacy of medical treatment or after revascularization, or to assist prescription of exercise after control of symptoms 1.
Conclusion Not Provided
As per the guidelines, the doctor will interpret the results in the context of your symptoms, medical history, and risk factors to determine appropriate next steps, which might include medication, lifestyle changes, or further diagnostic testing.