What is the management approach for a patient with a low ejection fraction (less than 40%), particularly in the context of heart disease?

Management of Low Ejection Fraction (<40%)

For patients with ejection fraction less than 40%, you must immediately initiate a four-pillar pharmacologic regimen consisting of ACE inhibitors (or ARBs/ARNI), evidence-based beta-blockers, aldosterone antagonists, and SGLT2 inhibitors, while simultaneously evaluating for device therapy eligibility. 1, 2

Immediate Pharmacologic Therapy

First-Line Medications (Start All Four Classes)

• ACE inhibitors should be started and continued indefinitely in all patients with LVEF <40% unless contraindicated, with titration to target doses used in clinical trials 1

• If ACE inhibitor intolerant, ARBs are recommended as the alternative for patients with LVEF <40% 1

• Consider sacubitril/valsartan (ARNI) as superior to enalapril for reducing cardiovascular death and heart failure hospitalization (HR 0.80,95% CI 0.73-0.87, p<0.0001), particularly in NYHA class II-IV patients 3

• Beta-blocker therapy must be limited to carvedilol, metoprolol succinate, or bisoprolol - these three agents specifically have proven mortality reduction in patients with LVEF ≤40% 1, 2

• Beta-blockers should be initiated even if asymptomatic and continued indefinitely 1

• Aldosterone blockade is recommended in patients already receiving ACE inhibitors and beta-blockers who have LVEF <40% and either diabetes or heart failure symptoms, provided no significant renal dysfunction (creatinine <1.8 mg/dL) or hyperkalemia exists 1

• SGLT2 inhibitors are now part of the foundational four-pillar therapy for HFrEF regardless of diabetes status 1

Adjunctive Therapy Based on Heart Rate

• If heart rate remains ≥70 bpm despite maximally tolerated beta-blocker therapy, add ivabradine 4
• Ivabradine reduced the composite endpoint of heart failure hospitalization or cardiovascular death (HR 0.82,95% CI 0.75-0.90, p<0.0001) in patients with LVEF ≤35% and heart rate ≥70 bpm on stable medical therapy 4

Symptom Management

• Diuretics should be adjusted to achieve euvolemia - increase doses for volume overload, then reassess GDMT titration within 1-2 weeks 1
• Loop diuretics are for symptom control only and do not improve mortality 1

Device Therapy Evaluation (Critical - Do Not Delay)

ICD Consideration

• ICD therapy for primary prevention is recommended in patients with LVEF ≤35% who have coronary artery disease or other structural heart disease and are expected to survive >1 year with good functional status 2
• The mortality benefit increases as EF decreases below 35%: patients with EF <30% show HR 0.72 versus EF 30-35% showing HR 0.83 2
• Patients ≥75 years still derive 24% mortality reduction from primary prevention ICD, though absolute benefit may be lower due to competing comorbidities 2
• Wait 3-6 months after optimal GDMT initiation before ICD implantation to allow for potential EF recovery, unless patient has survived sudden cardiac arrest 1

CRT Evaluation

• Cardiac resynchronization therapy should be evaluated if QRS duration ≥120 ms, particularly if ≥150 ms with left bundle branch block morphology 2
• CRT provides additional mortality benefit beyond ICD alone in appropriate candidates with LVEF ≤35% 2

Critical Pitfalls to Avoid

• Never delay device therapy evaluation while "optimizing" medical therapy - these interventions proceed in parallel for eligible patients 2
• Avoid nondihydropyridine calcium channel blockers (diltiazem, verapamil) in patients with LVEF ≤35% due to negative inotropic effects 2
• Do not consider patients with EF near 35-40% as "borderline" - they meet validated thresholds for high-risk interventions based on robust trial data 2
• Monitor renal function and potassium closely when initiating ACE inhibitors/ARBs and aldosterone antagonists, but do not withhold therapy for mild elevations 1

Follow-Up Strategy

• Schedule clinic visits every 1-2 weeks during medication titration with basic metabolic panel monitoring 1
• Repeat echocardiogram after 3-6 months of optimal GDMT to reassess LVEF for device therapy decisions 1
• Refer to advanced heart failure specialist if: requiring IV inotropes, NYHA class IIIB/IV despite GDMT, >1 hospitalization for heart failure, progressive intolerance of GDMT, or persistent symptoms despite maximal therapy 1

Special Consideration for Low Blood Pressure

• Low blood pressure should not be a barrier to GDMT initiation or maintenance unless systolic BP <80 mmHg or patient is symptomatic 1
• Address reversible non-heart failure causes of hypotension first, then stop non-heart failure medications before reducing GDMT 1
• Asymptomatic low blood pressure in the 80-100 mmHg range is common and well-tolerated in HFrEF patients on optimal therapy 1