Brief Description of Measure:

​CMS145: Coronary Artery Disease (CAD): Beta-Blocker Therapy-Prior Myocardial Infarction (MI) or Left Ventricular Systolic Dysfunction (LVEF less than 40%):
Percentage of patients aged 18 years and older with a diagnosis of coronary artery disease seen within a 12-month period who also have a prior MI or a current or prior LVEF <40% who were prescribed beta-blocker therapy

Description of Issue:

The intent of the measure is to include patients with Moderate or severe LVSD in Population 1 and limit Population 2 to patients with a history of MI without Moderate or Severe LVSD. However, it has been noted that ​patients are being included in both populations due to the current structure of the LVSD diagnosis in the definition.
The current logic captures patients with LVSD findings if the diagnosis Date/Time is after the Qualifying CAD Encounter. This erroneously captures patients in both Populations 1 and 2, as the intent of the measure is to include patients with Moderate or Severe LVSD in Population 1 and not Population 2.

Proposed Solution:

Update the denominator logic for Population 2 so that patients with LVSD will not be captured in the denominator.
Current Denominator Definition:
  "Qualifying CAD Encounter" EncounterWithCADProxy
    with ["Diagnosis": "Myocardial Infarction"] MyocardialInfarction
      such that MyocardialInfarction.prevalencePeriod starts 3 years or less before day of start of EncounterWithCADProxy.relevantPeriod
    without "Moderate or Severe LVSD Findings" LVSDFindings
      such that Coalesce(LVSDFindings.prevalencePeriod, Global."NormalizeInterval"(LVSDFindings.relevantDatetime, LVSDFindings.relevantPeriod))starts before
      end of EncounterWithCADProxy.relevantPeriod
Proposed Update:
"Qualifying CAD Encounter" EncounterWithCADProxy
  with ["Diagnosis": "Myocardial Infarction"] MyocardialInfarction
    such that MyocardialInfarction.prevalencePeriod starts 3 years or less before day of start of EncounterWithCADProxy.relevantPeriod
      and not exists "Moderate or Severe LVSD Findings"

Rationale for Change:

​The proposed change will prevent patients with Moderate or Severe LVSD Findings from being captured in the denominator of Population 2, regardless of the timing of the diagnosis/findings.