Guideline‑Directed Management of Incidentally Discovered Asymptomatic Reduced LVEF (≤ 40%)

Diagnostic Confirmation

• Obtain two consecutive LVEF measurements (using the same or a different imaging modality such as echocardiography, cardiac MRI, or radionuclide ventriculography) before committing to long‑term therapy, to account for measurement variability. – ACC/AHA guideline (Circulation 2008) 1
• In women and individuals with smaller body surface area, reduced LVEF may occur with less ventricular dilatation; therefore, indexing LV dimensions to body surface area can improve detection. – ACC/AHA guideline (Circulation 2008) 1

Pharmacologic Therapy (Four‑Pillar GDMT)

• Initiate an ACE inhibitor, ARB, or ARNI immediately; ARNI (sacubitril/valsartan) provides additional reduction in HF hospitalization and mortality compared with ACE‑inhibitor therapy. – ACC/AHA guideline (Circulation 2022) 2
• Start a guideline‑recommended beta‑blocker (carvedilol, metoprolol succinate, or bisoprolol) concurrently; beta‑blockers confer mortality benefit in HFrEF irrespective of symptom status. – ACC/AHA guideline (Circulation 2022) 2
• Add a mineralocorticoid receptor antagonist (spironolactone or eplerenone) for patients with LVEF ≤ 35%; monitor renal function and potassium (contraindicated if eGFR < 30 mL/min/1.73 m² or K⁺ > 5.0 mmol/L). – ACC/AHA guideline (Circulation 2022) 2
• Prescribe an SGLT2 inhibitor (dapagliflozin or empagliflozin) regardless of diabetes status; this class reduces cardiovascular mortality, all‑cause mortality, and HF hospitalization beyond standard neuro‑hormonal therapy. – ACC/AHA guideline (Circulation 2022) 2
• For African‑American patients with NYHA class III–IV symptoms, consider hydralazine/isosorbide dinitrate as an adjunct, which offers high economic value and additional outcome benefit. – ACC/AHA guideline (Circulation 2022) 2

Device Therapy

• Recommend an implantable cardioverter‑defibrillator (ICD) for primary prevention in patients with LVEF ≤ 35% who are ≥ 40 days post‑myocardial infarction (ischemic) or have non‑ischemic cardiomyopathy with expected survival > 1 year. – ACC/AHA guideline (Circulation 2022) 2
• Consider cardiac resynchronization therapy (CRT) when LVEF ≤ 35% is accompanied by left bundle‑branch block with QRS ≥ 150 ms and sinus rhythm, as CRT provides substantial clinical and economic benefit. – ACC/AHA guideline (Circulation 2022) 2

Monitoring & Surveillance

• Schedule clinical follow‑up every 3–6 months initially to evaluate symptom emergence and medication tolerance. – ACC/AHA guideline (Circulation 2022) 2
• Repeat transthoracic echocardiography every 6–12 months to track LVEF, ventricular dimensions, and the possibility of HF with improved EF (HFimpEF). – ACC/AHA guideline (Circulation 2022) and European Heart Journal 2022 [3][2]
• Continue full HFrEF GDMT even if LVEF improves above 40 % (HFimpEF), because abrupt discontinuation is associated with relapse. – ACC/AHA guideline (Circulation 2022) 2

Critical Pitfalls

• Do not postpone GDMT awaiting symptom development; early treatment in asymptomatic LV dysfunction reduces mortality and prevents progression to overt HF. – ACC/AHA guideline (Circulation 2022) 2
• Avoid reliance on a single LVEF measurement for definitive therapeutic decisions; confirm with repeat imaging to prevent misclassification. – ACC/AHA guideline (Circulation 2008) and JACC 2016 [1][4]

Special Populations

• In patients with concomitant moderate‑to‑severe valvular disease (e.g., aortic stenosis or mitral regurgitation), perform dedicated valve assessment to determine optimal timing of valve intervention alongside GDMT. – ACC/AHA guideline (Circulation 2008) and European Heart Journal 2021/2022 [1][5]3

Management of Heart Failure with Reduced Ejection Fraction

Classification and Diagnosis

• The American College of Cardiology classifies heart failure into three categories based on left ventricular ejection fraction (LVEF): heart failure with reduced ejection fraction (HFrEF) (LVEF <40%), heart failure with mid-range ejection fraction (HFmrEF) (LVEF 41-49%), and heart failure with preserved ejection fraction (HFpEF) (LVEF ≥50%) 6, 7
• Patients with HFrEF often present with symptoms of New York Heart Association (NYHA) class III-IV, including progressive dyspnea, lower extremity edema, and signs of congestion 6, 8
• Elevated B-type natriuretic peptide (BNP) levels confirm the diagnosis of decompensated heart failure 6, 8

Pharmacological Management

• The American College of Cardiology recommends the use of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor-neprilysin inhibitors (ARNIs) as first-line therapy for HFrEF patients, with a Class I indication 6, 9, 10
• Beta blockers are also recommended as first-line therapy for HFrEF patients, with a Class I indication 6, 9, 11
• Mineralocorticoid receptor antagonists (MRAs) are recommended for HFrEF patients with LVEF ≤35% despite ACEI and beta blocker therapy, with a Class I indication 10, 11
• Sodium-glucose cotransporter 2 (SGLT2) inhibitors, such as dapagliflozina or empagliflozina, should be added to the treatment regimen for HFrEF patients to reduce the risk of cardiovascular mortality, all-cause mortality, and hospitalization for heart failure, with a Class I indication 9, 12
• The European Heart Society recommends that ARNI (sacubitril/valsartán) should replace ACEI to further reduce the risk of hospitalization for heart failure and death in HFrEF patients 9, 10

Additional Therapies

• Ivabradina may be considered for HFrEF patients with a heart rate >70 bpm in sinus rhythm and persistent symptoms, with a Class IIa indication 6
• Hydralazine and isosorbide dinitrate may be considered for African American HFrEF patients with NYHA class III-IV symptoms, with a Class IIa indication 9, 12

Important Considerations

• SGLT2 inhibitors provide incremental benefit beyond fundamental neurohormonal therapy for HFrEF patients 9, 12
• MRAs should be used with caution in patients with impaired renal function (eGFR <30 mL/min) and hyperkalemia (K+ >5.0 mmol/L) 10, 11