For patients presenting to the ED with chest pain but no MI, the rate of short-term future MI was low and was not affected by early noninvasive testing.
Researchers conducted a retrospective cohort analysis of health insurance claims data for a national sample of privately insured patients with a primary or secondary diagnosis of chest pain in the ED in 2011.
Patients were stratified according to testing strategy: no noninvasive testing, exercise ECG, stress echocardiography, myocardial perfusion scintigraphy or coronary CTA.
Researchers calculated the proportion of patients who received a cardiac catheterization procedure, coronary revascularization procedure or future noninvasive test, as well as those hospitalized for acute MI during 7 days and 190 days of follow-up.
In total, the analysis included 421,774 patients, of whom 127,986 received an initial noninvasive test and 293,788 did not.
Overall rates of hospitalization for acute MI were 0.11% at 7 days and 0.33% at 190 days, Andrew J. Foy, MD, from the division of cardiology at Penn State Milton S. Hershey Medical Center, Hershey, Pa., and colleagues reported.
Testing had no impact on MI
The odds of hospitalization for acute MI were similar regardless of whether early noninvasive testing was conducted, according to the researchers. Compared with no early invasive testing, the odds of hospitalization for acute MI were not significantly different for patients who had:
- stress echocardiography (adjusted OR at 7 days=0.99; 95% CI, 0.65-1.51; adjusted OR at 190 days=0.83; 95% CI, 0.83-1.06);
- exercise ECG (adjusted OR at 7 days=1.33; 95% CI, 0.89-1.98; adjusted OR at 190 days=0.94; 95% CI, 0.73-1.22);
- myocardial perfusion scintigraphy (adjusted OR at 7 days=1.25; 95% CI, 1-1.54; adjusted OR at 190 days=1.03; 95% CI, 0.91-1.17); or
- coronary CTA (adjusted OR at 7 days=1.7; 95% CI, 0.7-4.14; adjusted OR at 190 days=1.2; 95% CI, 0.67-2.13).
The results did not differ by sex.
Although there was no improvement in odds of experiencing MI, patients who had exercise ECG were more likely to have cardiac catheterization (adjusted OR at 7 days=1.63; 95% CI, 1.5-1.78; adjusted OR at 190 days=1.33; 95% CI, 1.25-1.42) or revascularization (adjusted OR at 7 days=2.41; 95% CI, 2.09-2.8; adjusted OR at 190 days=1.55; 95% CI, 1.38-1.75) compared with those patients who received no noninvasive tests, according to the researchers. The same was observed for myocardial perfusion scintigraphy (adjusted OR for catheterization at 7 days=2.48; 95% CI, 2.38-2.58; adjusted OR for catheterization at 190 days=2.06; 95% CI, 2-2.13; adjusted OR for revascularization at 7 days=2.4; 95% CI, 2.21-2.61; adjusted OR for revascularization at 190 days=1.71; 95% CI, 1.61-1.82) and for coronary CTA (adjusted OR for catheterization at 7 days=1.91; 95% CI, 1.59-2.3; adjusted OR for catheterization at 190 days=1.37; 95% CI, 1.17-1.6; adjusted OR for revascularization at 7 days=3.56; 95% CI, 2.65-4.76; adjusted OR for revascularization at 190 days=1.95; 95% CI, 1.51-2.52).
Patients who had stress echocardiography were more likely to have cardiac catheterization (adjusted OR=1.1; 95% CI, 1.01-1.2) and revascularization (adjusted OR=1.54; 95% CI, 1.31-1.81) at 7 days, but there was no difference at 190 days for either compared with patients who received no noninvasive testing.
“Our results suggest that in a cohort of patients presenting to the ED with chest pain, the increased detection and treatment of [CAD] via [coronary] CTA, [myocardial perfusion scintigraphy] and [exercise ECG] may be of little or no value,” Foy and colleagues wrote.
Current practice unnecessary
Rita F. Redberg
In an editor’s note, Rita F. Redberg, MD, MSc, professor of medicine at the University of California, San Francisco, and chief editor of JAMA Internal Medicine, wrote that “these findings suggest that the current practice of performing a stress test on low-risk patients in the ED is unnecessary and prolongs the length of stay in EDs as well as increases unnecessary medical imaging, with a significant associated radiation risk for tests that include nuclear imaging.”
Redberg, a member of Cardiology Today’s Editorial Board, wrote that “it is time to change our guidelines and practice for treatment of chest pain in low-risk patients. Such patients should be given a close follow-up appointment with a primary care physician who can determine, based on the patient’s condition, whether further evaluation is necessary.”
For more information:
Foy AJ. JAMA Intern Med. 2015:doi:10.1001/jamainternmed.2014.7657.
Redberg RF. JAMA Intern Med. 2015:doi:10.1001/jamainternmed.2014.7698.
Disclosure: The researchers and Redberg report no relevant financial disclosures.