Measure Description: Percentage of patients age ≥18 y with a diagnosis of heart failure with a current or prior LVEF ≤40% who were prescribed ACE inhibitor, ARB, or ARNI either within a 12-mo period when seen in the outpatient setting or at hospital discharge
Numerator	Patients who were prescribed* ACE inhibitor, ARB, or ARNI either within a 12-mo period when seen in the outpatient setting or at hospital discharge *Prescribed may include: Outpatient setting: Prescription given to the patient for ACE inhibitor, ARB, or ARNI at ≥1 visits in the 12-mo measurement period or patient already taking ACE inhibitor, ARB, or ARNI as documented in current medication list. Inpatient setting: Prescription given to the patient for ACE inhibitor, ARB, or ARNI at discharge or ACE inhibitor, ARB, or ARNI to be continued after discharge as documented in the discharge medication list.
Denominator	All patients age ≥18 y with a diagnosis of heart failure with a current or prior LVEF ≤40%
Denominator Exclusions	Heart transplant LVAD
Denominator Exceptions	Documentation of medical reason(s) for not prescribing ACE inhibitor, ARB, or ARNI (e.g., intolerance) Documentation of patient reason(s) for not prescribing ACE inhibitor, ARB, or ARNI (e.g., patient refusal)
Measurement Period	ACE inhibitor, ARB, or ARNI therapy initiated within a 12-mo period of being seen in the outpatient setting or from hospital discharge
Sources of Data	EHR data Administrative data/claims (inpatient or outpatient claims) Administrative data/claims expanded (multiple sources) Paper medical record
Attribution	Individual practitioner Facility
Care Setting	Outpatient Inpatient
Rationale
Use of ACE inhibitor, ARB, or ARNI therapy has been associated with improved outcomes in patients with reduced LVEF (7). Long-term therapy with ARBs has also been shown to reduce morbidity and mortality, especially in ACE inhibitor-intolerant patients (41–44). More recently, ARNI therapy has also been shown to more significantly improve outcomes (45), such that the newest guidelines recommend replacement of ACE inhibitors or ARBs with ARNI therapy in eligible patients (4). However, despite the benefits of these drugs, use of ACE inhibitor, ARB, or ARNI remains suboptimal (20).
Clinical Recommendation(s)
2017 ACC/AHA/HFSA heart failure guideline update (4) 1. The clinical strategy of inhibition of the renin-angiotensin system with ACE inhibitors (Class 1, Level of Evidence: A) (46–51), OR ARBs (Class 1, Level of Evidence: A) (41–44), OR ARNI (Class 1, Level of Evidence: B-R) (45) in conjunction with evidence-based beta blockers (7,33,52), and aldosterone antagonists in selected patients (53,54), is recommended for patients with chronic HFrEF to reduce morbidity and mortality.

ACC indicates American College of Cardiology; ACCF, American College of Cardiology Foundation; ACE, angiotensin–converting enzyme; AHA, American Heart Association; ARB, angiotensin receptor blocker; ARNI, angiotensin receptor–neprilysin inhibitor; EHR, electronic health record; HFrEF, heart failure reduced ejection fraction; HFSA, Heart Failure Society of America; LVAD, left ventricular assist device; LVEF, left ventricular ejection fraction; and PM, performance measure.