Is a treadmill stress test better than Coronary Computed Tomography Angiography (CTA) in assessing coronary artery disease?

From the Guidelines

Neither a treadmill stress test nor coronary CT angiography (CTA) is universally "better" for assessing heart disease; the choice depends on the specific clinical situation, with the most recent evidence from 2020 suggesting that coronary CTA is a proven alternative to stress testing or selective coronary angiography in stable patients with suggested acute coronary syndrome at low or intermediate risk of adverse events 1.

Key Considerations

• Treadmill stress testing is often used as a first-line test for patients with intermediate risk of coronary artery disease who can exercise adequately, providing functional information about how the heart performs under physical stress, as recommended by the 2013 ESC guidelines 1.
• Coronary CTA, on the other hand, provides detailed anatomical imaging of the coronary arteries and can detect coronary stenosis, plaque characteristics, and anomalies with high sensitivity, making it particularly useful for patients with atypical symptoms, inconclusive stress tests, or those unable to exercise adequately.
• The choice between these tests should be individualized based on the patient's age, symptoms, risk factors, ability to exercise, and other clinical considerations, with the American College of Physicians recommending exercise perfusion imaging or exercise echocardiography as the initial test for risk stratification in patients with chronic stable angina who are able to exercise 1.
• In some cases, a combination of both functional and anatomical testing may provide the most comprehensive assessment of coronary artery disease, as suggested by the 2020 ACR Appropriateness Criteria for chest pain-possible acute coronary syndrome 1.

Clinical Evidence

• A study published in 2020 found that coronary CTA has a very high negative predictive value for the detection of coronary atherosclerosis with or without significant stenosis, making it an alternative to stress imaging in the emergency department and inpatient settings in patients at low to intermediate risk for CAD 1.
• The 2013 ESC guidelines recommend exercise ECG as the initial test for establishing a diagnosis of stable coronary artery disease 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.
• The American College of Physicians recommends against "screening" asymptomatic outpatients for coronary disease, but recognizes the clinical reality that primary care physicians and subspecialists may need to evaluate asymptomatic patients with risk factors for CAD 1.

From the Research

Comparison of Treadmill Stress Test and Coronary CTA

• The choice between a treadmill stress test and coronary computed tomography angiography (CTA) for assessing heart disease depends on various factors, including the patient's symptoms, medical history, and risk profile 2, 3.
• Coronary CTA is excellent at identifying anatomic coronary artery disease (CAD), while functional stress testing is better at evaluating the physiological significance of CAD 4.
• Studies have shown that coronary CTA is associated with a lower risk of myocardial infarction (MI) and similar risk of all-cause mortality compared to functional testing 2.
• However, the use of coronary CTA is also associated with higher costs and greater use of invasive procedures, such as percutaneous coronary intervention (PCI) 2.

Diagnostic Accuracy of Treadmill Stress Test and Coronary CTA

• The diagnostic accuracy of treadmill stress testing and coronary CTA varies depending on the patient population and the specific test used 5, 6.
• In patients aged ≥ 70 years, bicycle stress echocardiography was found to be more accurate than exercise treadmill testing (ETT) for detecting obstructive CAD 6.
• ETT had a sensitivity of 79% and specificity of 82% for detecting obstructive CAD, while stress echocardiography had a sensitivity of 89% and specificity of 95% 6.

Prognostic Value of Treadmill Stress Test and Coronary CTA

• The prognostic value of coronary CTA and ETT has been compared in several studies, with results suggesting that coronary CTA provides incremental risk stratification for future cardiovascular events in patients with intermediate- to high-risk ETT results 5.
• In patients with low-risk ETT results, the presence of non-obstructive or obstructive CAD on coronary CTA did not predict increased risk for cardiovascular death or MI 5.