Re: Predictive Value of Exercise Stress Testing in a Family Medicine Population

To the Editor: This study adds perspective to the role of exercise stress testing (EST) in triaging primary care patients with cardiac symptoms or risk factors. It also belies its first sentence, “Exercise stress testing (EST) is a screening test for coronary artery disease.”¹

Only 2.3% of the studied patients presented for screening. Another 31% of patients received EST for no listed indication or for pre-exercise evaluation. Though the retrospective study design limits our insight, it is more likely than not that these additional patients had cardiac symptoms or risk factors.

In this study, all patients with positive cardiac outcomes, regardless of EST results, had at least 1 risk factor. All asymptomatic patients had a very low or low pretest probability of coronary artery disease, with associated high negative predictive values (NPVs) of EST. Unless triage of at-risk (by symptoms or risk factors) primary care patients is conflated with screening (attempts to detect treatable presymptomatic disease), this combination of findings affirms both the effectiveness of EST in triage and the lack of effectiveness of EST in screening.