Thank you for your inquiry regarding CMS996v5, Appropriate Treatment for ST-Segment Elevation Myocardial Infarction (STEMI) Patients in the Emergency Department (ED). The measure does not currently use timing of electrocardiograms (EKGs). This decision was based on clinical expert input and measure testing results, which indicate that EKG timing in electronic health record (EHR) documentation is unreliable. Additionally, the issue of the measure not excluding cases where the STEMI develops during the ED encounter, but the measure still assesses appropriate treatment starting from ED arrival time, will be assessed in a future annual update. The measure developer will consider adding a denominator exception, during a future Annual Update, for encounters in which there is a documented reason for not performing the measure’s numerator criteria, indicated by broad value sets for patient refusal, procedure/drug intervention not indicated/contraindicated, etc.. Furthermore, the measure developer will consider adding a denominator exclusion, specific to encounters in which a patient left against medical advice, in a future Annual Update. The measure developer will consider refinements to the measure logic and value set refinements, in accordance with clinical guidelines om a future annual update. Value sets used for measure exclusion criteria are broad, to accommodate various clinical scenarios for inclusion in the measure’s initial population.