Sometimes, more isn’t better. Research suggests that myocardial perfusion scintigraphy and coronary computed tomography angiography may be bringing more patients with chest pain to the cath lab following a trip to the emergency room than is necessary.

As many as one in 27 patients who undergo MPS and one in 71 who undergo CCTA following a visit to the emergency department for chest pain ultimately undergo catheterization, according to a study published online Jan. 26 in JAMA: Internal Medicine. However, among similar emergency room patients who either underwent noninvasive or no testing, far fewer had either catheterization or revascularization outcomes.

Andrew J. Foy, MD, from the Penn State Milton S. Hershey Medical Center in Hershey, and colleagues retrospectively reviewed U.S.-wide insurance claims data from 2011 for their analysis. Patients fit into one of five categories: no testing, stress echocardiography, electrocardiography, MPS or CCTA. Cases were reviewed through seven and 190 days follow-up post-emergency room visit. Foy et al looked for how many ultimately had cardiac catheterization, coronary revascularization procedure or future noninvasive test and hospitalizations for acute MI.

Few patients, between 0.1 percent and 0.2 percent, had subsequent MI, regardless of whether or not a test was performed. However, odds were high for invasive tests that future catheterization or revascularization would be performed. At seven days, odds of catheterization or revascularization following MPS was 2.48 and 2.4, respectively; post-CCTA patient odds for catheterization or revascularization were 1.91 and 3.58, respectively. At 190 days, odds for revascularization or catheterization were still higher for MPS (1.71 and 2.06) or CCTA (1.95 and 1.37) than among noninvasive testing or no-testing patients.

Foy et al noted that stress echocardiography appeared to be the most effective noninvasive test “since it was associated with the least number of catheterization and revascularization procedures and no significant difference in hospitalizations for MI.” They suggested that while other modalities may be more precise, rates of overdiagnosis may be increased, leading to unnecessary testing and therapies.

“Overall, our results suggest that in a cohort of patients presenting to the ED [emergency department] with chest pain, the increased detection and treatment of coronary artery disease via CCTA, MPS, and EE [exercise electrocardiography] may be of little or no value,” they wrote.

Foy et al called for more randomized trials comparing strategies to provide further data to the discussion. “Given today’s concerns regarding health care cost growth, especially the portion attributable to noninvasive cardiac imaging, and patient safety issues related to radiation exposure as well as overdiagnosis, performing such a study should be a priority.”