Coronary artery computed tomography angiography of the heart (CCTA) is one of the most sensitive tests to detect serious CAD in appropriately selected patients.In 85% of acute chest pain (ACP) ED cases tested by CCTA, no CAD or very mild CAD is found, leading to rapid discharge or an alternative diagnosis. However, in the 15% of patients with significant CAD found on CCTA, further evaluation with either stress testing or heart catheterization, and/or hospital admission is required. Since 2015, Beaumont Health hospitals have employed a new FDA-approved test, called CT fractional flow reserve (CTFFR), that can analyze flow down the heart arteries by computer analysis of the original CT images. Results from an analysis of 147 patients suggest that 67% of the time, CTFFR showed no significant flow limitation, providing for the potential to defer invasive testing or treatment for a trial of medical therapy.