PROMISE Subanalysis: Potential Benefits of CT Angiography over Functional Studies in Patients with Symptoms Suggesting CAD

Original Title: Outcomes of anatomical versus functional testing for coronary artery disease.
Presenter: Douglas PS.

Early this year, the PROMISE trial was not able to confirm that testing patients with chest painusingcomputed tomography angiography (CTA) instead of functional tests, affects clinical outcomes, even though several sub analysis are currently suggesting other additional benefits,including enhanced diagnostic accuracy and safety, and preventive use of medication.

The PROMISE randomized10,003 symptomatic patients to a strategy of initial anatomical testing with the use of coronary computed tomographic angiography (CTA) or to functional testing (exercise electrocardiography, nuclear stress testing, or stress echocardiography) to rule out CAD. Published in March 2015, its main outcomes confirmed that the composite primary end point of death, myocardial infarction, hospitalization for unstable angina, or major procedural complication, was similar between the CTA group and the functional testing group (3.3% vs 3.0%) through a median follow up of 25 months. However, secondary analyzes suggest there could be differences between these two strategies.

Findings were classified into normal, mildly abnormal, moderately abnormal and severely abnormal. The ratio of normal outcomes was lower in the CTA arm, compared to the functional testing arm (33.3% vs 78.0%; p=0.001).
The more accurate prognosis of CTA was confirmed by a higher netreclassification index(0.67 vs 0.40).

Findings predefined as significant were observed in 12% of patients undergoing CTA, including 9% of lung nodules, 1.5% of coronary anomalies and proportions with pulmonary embolism, pneumonia and aortic aneurysm or dissection.

Given these findings, the lower radiation dose and the capacity to detect potential clinically important pathologies, CTA has become an attractive first choice test for patients with suspected CAD.