The Particulars: Studies have suggested that myocardial perfusion imaging is a poor prognostic factor in patients who achieve a high exercise level during stress testing. However, outcomes data are lacking with regard to testing of protocols in ED patients presenting with chest pain.
Data Breakdown: Researchers at Mount Sinai implemented a protocol in which ED patients presenting with chest pain were referred for stress testing. They did not undergo a radioisotope injection if they were younger than age 65 and had a normal rest electrocardiogram (ECG), no history of coronary artery disease (CAD), high levels of exercise, no symptoms, and a negative ECG response. No significant differences were observed between these patients and those who underwent a radioisotope injection with regard to cardiac mortality or repeat function stress tests ordered. However, patients who did not receive a radioisotope injection had significantly fewer angiograms and a trend toward fewer revascularizations.
Take Home Pearls: A protocol in which acute chest pain patients referred to imaging do not undergo a radioisotope injection based on age, ECG results, history of CAD, symptoms, and exercise level appears to result in low mortality and few follow-up diagnostic tests. Adoption of the protocol may decrease radiation exposure and save time and related costs, without jeopardizing prognosis.