Thank you for your inquiry regarding CMS996: Appropriate Treatment for ST-Segment Elevation Myocardial Infarction (STEMI) Patients in the Emergency Department (ED). Any STEMI diagnosis coded during the ED encounter will be included in the measure. STEMI diagnoses may be found in a patient’s problem list, encounter diagnosis list, claims data, or other sources within the EHR. First, a STEMI diagnosis can be pulled directly from the ED encounter if a STEMI diagnosis was coded during the encounter. Second, the patient can have a diagnosis pulled from a claim, problem list, or other source in the EHR if the prevalencePeriod of the STEMI diagnosis started during the ED encounter relevantPeriod. However, the updated CMS996v6 STEMI measure specifications for the 2026 reporting period include denominator exceptions for ED encounters with a documented reason (such as patient refusal) for (i) not administering fibrinolytic therapy within 30 minutes of ED arrival or (ii) not performing a PCI within 90 minutes of ED arrival. Reasons for not performing a PCI are captured using the “Procedure, Not Performed” data type together with the “Patient Refusal” (OID: 2.16.840.1.113883.3.117.1.7.1.93) and “Procedure Not Indicated/Contraindicated" (OID: 2.16.840.1.113762.1.4.1282.2) value sets. The “Procedure Not Indicated/Contraindicated" value sets cover scenarios where a PCI is not indicated due to non-STEMI findings or other reasons. The value sets can be found in the Value Set Authority Center (VSAC) by searching each value set’s OID [ https://vsac.nlm.nih.gov/welcome ]. Please note that you may need to create a free account to view these codes.