I previously reached out with a question regarding which diagnosis should be included in the capture of STEMI in CMS996v6 – Appropriate Treatment for ST‑Segment Elevation Myocardial Infarction (STEMI) eCQM. Unfortunately, the response (did not address the specific scenario we are concerned about.

As I understand it, the measure denominator includes all emergency department (ED) encounters with a documented STEMI diagnosis during the ED visit, typically based on the admitting or initial ED diagnosis, while the numerator requires that the patient receive timely STEMI-specific treatment (fibrinolysis or PCI) during the ED encounter.

We seek clarification on the following scenario:

A patient presents to the ED with an admitting/provisional diagnosis of STEMI, but after further evaluation outside the ED (e.g., following hospital admission or CathLab evaluation), the final confirmed diagnosis is determined not to be STEMI.

1. Does the initial ED/admitting diagnosis alone place the patient in the CMS996v6 denominator, even if STEMI-specific treatment is not administered?

1. If the final diagnosis rules out STEMI after leaving the ED, should the patient still be counted in the denominator for measure reporting purposes?

1. Does CMS provide guidance or exceptions for cases where the ED initially suspected STEMI, but subsequent evaluation confirms STEMI was not present?

We note that the measure specifications (as posted in [eCQI|Appropriate Treatment for ST-Segment Elevation Myocardial Infarction (STEMI) Patients in the Emergency Department (ED) 5.1.000]) do not define the type of diagnosis required, which creates potential confusion. Clinically, only a confirmed STEMI would warrant STEMI-specific treatment such as fibrinolysis or PCI. Including patients whose STEMI was ruled out after ED evaluation could result in denominator cases where treatment is not appropriate, thereby artificially lowering performance.

We are seeking explicit verification of how CMS defines “diagnosis” for this measure in scenarios where the final confirmed diagnosis occurs after the ED encounter, to ensure accurate and compliant reporting.

Thank you for your guidance and clarification.