Investigating chest pain: anatomy or function?

Among patients with chest pain, it is unclear if anatomic assessment of coronary obstruction or functional assessment with stress testing leads to better patient outcomes. In this randomized controlled trial of 10,003 symptomatic patients, individuals were randomly assigned in a 1:1 fashion to either anatomical testing with coronary CT angiography (CTA) or to functional testing by one of several different modalities (exercise ECG (10%), nuclear stress testing (67%) or stress echo (23%)).  Instead of diagnostic accuracy, as is seen with most such studies, the trial was powered for clinical outcomes with a primary composite endpoint of death, myocardial infarction, hospitalization for unstable angina, or major procedural complication.  The study patients were a mean age 61 years, 53% were women, and the mean pretest probability of coronary artery disease was 53±21%.  Over a median follow-up of 25 months, the rate of the primary-end point was similar in patients undergoing CTA (3.3%) and functional testing (3.0%) (HR, 1.04; 95% CI, 0.83 to 1.29; P=0.75).  More patients in the CTA group underwent cardiac catheterization and there was greater radiation exposure in the CTA group (12.0 mSv vs. 10.1 mSv; P<0.001) with 32.6% of patients in the functional-testing group having no radiation exposure.

Conclusions

In patients presenting with chest pain who require diagnostic testing for coronary disease, an initial strategy of anatomic testing with CTA in comparison with a functional test does not lead to any appreciable improvement in patient outcomes.

  • Douglas PS, Hoffmann U, Patel MR, Mark DB, Al-Khalidi HR, Cavanaugh B, Cole J, Dolor RJ, Fordyce CB, Huang M, Khan MA, Kosinski AS, Krucoff MW, Malhotra V, Picard MH, Udelson JE, Velazquez EJ, Yow E, Cooper LS and Lee KL Outcomes of anatomical versus functional testing for coronary artery disease. N Engl J Med. 2015 Apr 2;372(14):1291-300.

Written by Hussain Contractor and Steven Bradley.