How should I manage an adult patient with heart failure, including assessment of ejection fraction (≤40% vs ≥50%), NYHA class, renal function, electrolytes, blood pressure, and comorbidities, and selection of guideline‑directed medical and device therapies?

Management of Heart Failure

Begin with transthoracic echocardiography to measure left ventricular ejection fraction (LVEF), which determines your entire treatment algorithm: HFrEF (LVEF ≤40%) requires immediate four-pillar guideline-directed medical therapy (GDMT), HFmrEF (LVEF 41-49%) warrants similar neurohormonal blockade, and HFpEF (LVEF ≥50%) focuses on SGLT2 inhibitors, comorbidity management, and symptom control. 1

Initial Diagnostic Assessment

Essential Testing

• Measure LVEF via transthoracic echocardiography to classify heart failure phenotype and guide all subsequent therapy 1
• Obtain BNP or NT-proBNP levels to confirm diagnosis and establish prognosis; elevated natriuretic peptides are required for diagnostic certainty 1
• Assess NYHA functional class (I-IV) based on dyspnea severity: Class I = asymptomatic, Class II = symptoms with moderate exertion, Class III = symptoms with minimal exertion, Class IV = symptoms at rest 1
• Check baseline renal function (creatinine, eGFR) and electrolytes (sodium, potassium) before initiating any GDMT, as these determine medication safety and dosing 1, 2
• Measure blood pressure and heart rate to guide beta-blocker and RAAS inhibitor titration 1
• Screen for reversible causes: coronary ischemia via stress testing or coronary angiography, significant valvular disease via echocardiography, and thyroid dysfunction 1

Risk Stratification

• Obtain cardiac MRI for tissue characterization when ischemic versus non-ischemic etiology remains unclear, as this determines ICD candidacy 1
• Check baseline troponin for prognostic stratification, particularly in acute decompensation 1

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Management of HFrEF (LVEF ≤40%)

Four-Pillar Pharmacologic Therapy (Initiate ALL Four Classes)

Start all four medication classes simultaneously or in rapid sequence—do not wait for symptoms to worsen or for sequential titration of one class before adding the next. 3, 4

Pillar 1: RAAS Inhibition

• Initiate ARNI (sacubitril/valsartan) as first-line therapy over ACE inhibitors or ARBs, as ARNI provides superior reduction in cardiovascular mortality and heart failure hospitalization 3, 4
• If ARNI is not available or affordable, use an ACE inhibitor (enalapril, lisinopril, ramipril) 1
• Use ARB (losartan, valsartan, candesartan) only if ACE inhibitor causes intolerable cough 1
• Titrate to target or maximally tolerated doses over 4-8 weeks while monitoring blood pressure, renal function, and potassium 1

Pillar 2: Beta-Blocker

• Start carvedilol, metoprolol succinate, or bisoprolol concurrently with RAAS inhibition, as beta-blockers reduce mortality regardless of symptom status 3, 4
• Titrate to target heart rate of 50-60 bpm or maximally tolerated dose 1
• Do not withhold beta-blockers in stable patients with mild volume overload; optimize diuretics instead 4

Pillar 3: Mineralocorticoid Receptor Antagonist (MRA)

• Add spironolactone or eplerenone for all patients with LVEF ≤35% and NYHA class II-IV symptoms 1
• Contraindications: eGFR <30 mL/min/1.73 m² OR potassium >5.0 mEq/L OR creatinine >2.5 mg/dL (men) or >2.0 mg/dL (women) 1, 3
• Monitor potassium and creatinine at 3 days, 1 week, then monthly for 3 months after initiation to detect life-threatening hyperkalemia 1

Pillar 4: SGLT2 Inhibitor

• Prescribe dapagliflozin 10 mg daily or empagliflozin 10 mg daily regardless of diabetes status, as SGLT2 inhibitors reduce cardiovascular mortality, all-cause mortality, and heart failure hospitalization beyond neurohormonal therapy 3, 4, 5
• This class provides incremental benefit even when added to optimal triple neurohormonal blockade 3, 4

Additional Pharmacologic Therapies

Loop Diuretics

• Use furosemide, torsemide, or bumetanide to relieve congestion and edema, titrating to the lowest dose that maintains euvolemia 2, 4
• Monitor for worsening hyponatremia, hypokalemia, and renal dysfunction with chronic diuretic use 2

Ivabradine

• Add ivabradine for patients with LVEF ≤35%, sinus rhythm, heart rate ≥70 bpm despite maximally tolerated beta-blocker, and persistent NYHA class II-III symptoms 1, 3

Hydralazine/Isosorbide Dinitrate

• Prescribe for self-identified Black or African American patients with NYHA class III-IV symptoms already on ACE inhibitor/ARB/ARNI and beta-blocker, as this combination reduces mortality in this population 1, 3

Device Therapy

Implantable Cardioverter-Defibrillator (ICD)

• Recommend ICD for primary prevention in patients with LVEF ≤35% who are ≥40 days post-MI (ischemic) or have non-ischemic cardiomyopathy with expected survival >1 year and NYHA class II-III on GDMT 1, 3, 4
• ICD provides high economic value when risk of ventricular arrhythmia is high and risk of non-arrhythmic death is low 4

Cardiac Resynchronization Therapy (CRT)

• Implant CRT-D (or CRT-P) for patients with LVEF ≤35%, sinus rhythm, left bundle branch block (LBBB) with QRS ≥150 ms, and NYHA class II-IV symptoms on GDMT 1, 3, 4
• CRT provides substantial clinical and economic benefit in this population 4
• Consider CRT (Class IIa/IIb) for LBBB with QRS 120-149 ms 1

Monitoring and Follow-Up

• Schedule clinical follow-up every 3-6 months initially to evaluate symptom progression and medication tolerance 3
• Repeat echocardiography every 6-12 months to track LVEF and assess for heart failure with improved ejection fraction (HFimpEF) 3, 4
• Continue full four-pillar GDMT even if LVEF improves above 40% (HFimpEF), as abrupt discontinuation causes relapse of heart failure and left ventricular dysfunction 3, 4

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Management of HFmrEF (LVEF 41-49%)

• Treat with the same four-pillar GDMT as HFrEF (ARNI/ACE inhibitor/ARB, beta-blocker, MRA, SGLT2 inhibitor), as patients with HFmrEF have clinical profiles and prognosis closer to HFrEF than HFpEF and may benefit from neurohormonal blockade 1, 6
• Use loop diuretics for volume management 1
• ICD and CRT indications are less established; consider on a case-by-case basis for LVEF approaching 35% with other high-risk features 6
• Monitor LVEF serially, as HFmrEF is a dynamic state that may progress to HFrEF or improve to HFpEF 1, 6, 7

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Management of HFpEF (LVEF ≥50%)

Pharmacologic Therapy

• Prescribe SGLT2 inhibitor (dapagliflozin or empagliflozin) as first-line disease-modifying therapy, as this class reduces heart failure hospitalization and cardiovascular mortality in HFpEF 8
• Use loop diuretics for volume control and symptom relief 1
• Aggressively manage hypertension with a "stepped care" approach using GDMT agents (ACE inhibitors, ARBs, beta-blockers, MRAs) to target blood pressure <130/80 mmHg 1
• Treat coronary ischemia with revascularization and anti-ischemic medications 1
• Consider non-steroidal MRA (finerenone) and GLP-1 receptor agonists, especially in obese and diabetic patients, as emerging evidence supports phenotypic tailoring 8
• ARNI may be considered for selected patients with HFpEF, though evidence is less robust than in HFrEF 8

Comorbidity Management

• Optimize treatment of atrial fibrillation, diabetes, obesity, sleep apnea, chronic kidney disease, and coronary microvascular dysfunction, as HFpEF is a comorbidity-driven syndrome 8, 9
• Use metformin for initial diabetic control in HFpEF patients with diabetes 1
• Emphasize weight loss and exercise training for obese patients with HFpEF 8

Device Therapy

• ICD and CRT are generally not indicated unless LVEF declines or specific arrhythmic indications arise 9

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Special Considerations

Asymptomatic Left Ventricular Dysfunction (NYHA Class I)

• Obtain two consecutive LVEF measurements before committing to long-term therapy to account for measurement variability 3
• Initiate all four pillars of GDMT immediately (ARNI/ACE inhibitor, beta-blocker, MRA if LVEF ≤35%, SGLT2 inhibitor), as early treatment in asymptomatic LV dysfunction reduces mortality and prevents progression to overt heart failure 3
• Do not postpone GDMT awaiting symptom development 3

Hyponatremia in Heart Failure

• Determine if hyponatremia is hypervolemic or hypovolemic 2
• Treat hypervolemic hyponatremia with fluid restriction (1.5-2 L/day) and loop diuretics titrated to lowest dose maintaining euvolemia 2
• Reserve tolvaptan for persistent symptomatic hyponatremia refractory to fluid restriction and diuretics 2
• Continue ACE inhibitors and beta-blockers unless severe hemodynamic instability is present, as mortality benefits outweigh concerns about mild hyponatremia 2

Acute Decompensated Heart Failure

• Measure BNP/NT-proBNP and troponin on admission for prognostic stratification 1
• Check pre-discharge natriuretic peptide level to establish post-discharge prognosis 1
• Optimize GDMT before discharge and ensure close outpatient follow-up 1

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Critical Pitfalls to Avoid

• Do not rely on a single LVEF measurement for definitive therapeutic decisions; confirm with repeat imaging to prevent misclassification 3
• Do not delay initiation of all four GDMT pillars in HFrEF; start simultaneously or in rapid sequence rather than sequentially titrating one class at a time 3, 4
• Do not discontinue GDMT if LVEF improves above 40%; continue full therapy to prevent relapse 3, 4
• Do not use MRA if eGFR <30 mL/min/1.73 m² or potassium >5.0 mEq/L, as this causes life-threatening hyperkalemia 1, 3
• Do not withhold beta-blockers in stable patients with mild congestion; optimize diuretics instead 4
• Do not assume HFpEF is benign; aggressively manage comorbidities and initiate SGLT2 inhibitors 8, 9