Thank you for your inquiry regarding CMS996: Appropriate Treatment for ST-Segment Elevation Myocardial Infarction (STEMI) Patients in the Emergency Department (ED). This measure captures the percentage of ED encounters for patients 18 years and older with a diagnosis of STEMI who received appropriate treatment, defined as fibrinolytic therapy within 30 minutes of ED arrival, PCI within 90 minutes of ED arrival, or discharge to a PCI-capable Acute Care Facility within 45 minutes of ED arrival. The measure does not exclude patients transferred from outside hospitals as this does not align with measure intent. Regardless of whether a patient was transferred to the ED, they should still receive appropriate treatment for a STEMI occurring during the ED encounter in alignment with numerator criteria, unless the patient meets a denominator exclusion or exception criterion. We highlight that if a patient received fibrinolytic therapy at the prior facility within 24 hours of the ED encounter, they would not count towards the measure denominator. Furthermore, the issue of the measure not excluding patients who refuse treatment has previously been brought to CMS’s attention. CMS and the measure developer will consider this measure refinement during the next Annual Update. Lastly, patients who do not have a STEMI diagnosis during the ED encounter, and instead present with a STEMI during the inpatient encounter after ED discharge are not captured in the measure denominator. To indicate that the ED encounter has ended once the patient is discharged from the ED to receive inpatient care, we recommend proper documentation of both the ED discharge time and the ED discharge disposition of “Discharge to Acute Care Facility.”