Background: Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is a powerful noninvasive diagnostic and prognostic tool in patients with suspected coronary artery disease (CAD) with a Ͻ1% annual cardiac event rate in patients with normal studies. However, the length of the test and radiation exposure are often cited as negative attributes. In traditional rest-stress studies where the stress perfusion is normal, the rest portion of the test appears to be redundant. The purpose of our study was to ascertain the prognosis of a normal stress-only SPECT MPI study. Methods: We retrospectively analyzed the 3 month prognosis of all patients who had Tc-99m gated stress SPECT imaging between January 2004 and March 2005 using a single stress dose of isotope. Patients with abnormal stress MPI were scheduled for follow-up rest imaging. Stressors included exercise or coronary vasodilators (dipyridamole or adenosine). The decision not to perform the rest part of the study was decided by the attending nuclear cardiologist based on available clinical data, rest ECG's, patient's weight, and level of cooperation. Pre-test probability of CAD was calculated using a validated clinical score. Patients with documented CAD were classified as high pre-test probability. A normal stress study was defined as the absence of perfusion defects on stress images and an ejection fraction of 50%. Three month survival was assessed in all patients through medical records and the Social Security Death Index. Results: A total of 379 patients were found where 53% were female with a mean age 52 Ϯ 14 years and 47 (12%) had diabetes with 7 (2%) having known CAD. The pre-test probability of CAD was high in 39 (10.3%), intermediate in 205 (54.1%), and low in 135 (35.6%). Normal stress perfusion and normal LVEF was present in 326 (86%) patients; 14 patients (4%) had normal perfusion but abnormal ejection fraction (cardiomyopathy); and 39 patients (10%) had abnormal perfusion. Of those with a normal "stress-only" MPI study, 8 patients (2.5%) had died by 3 months. Six patients (1.5%) died of noncardiac causes and the cause of death in 2 patients (0.5%) was unknown and was considered cardiac. Therefore, based on a worse case scenerio, the 3 month cardiac mortality in this cohort was Յ0.5%. Conclusions: Normal "stress-only" gated Tc-99m SPECT MPI imaging has excellent short-term prognosis. The shortened test duration, lower received radiation dose, and excellent prognosis suggest that the "stress-only" study is an attractive option in appropriately selected patients.