What is the management for an asymptomatic patient with a history of Heart Failure with Reduced Ejection Fraction (HFrEF) and an ejection fraction of 33% presenting with bradycardia?

Management of Asymptomatic Patient with HFrEF 33% and Bradycardia (HR 36 bpm)

For an asymptomatic patient with HFrEF (EF 33%) and severe bradycardia (HR 36 bpm), permanent pacemaker implantation is recommended to allow for optimization of guideline-directed medical therapy (GDMT) and reduce mortality risk. 1

Initial Assessment

• Evaluate for signs of hemodynamic compromise despite asymptomatic status (mental status, blood pressure, urine output) 1
• Review current medications that may contribute to bradycardia (beta-blockers, non-dihydropyridine calcium channel blockers, digoxin) 1
• Assess for reversible causes of bradycardia (electrolyte abnormalities, hypothyroidism, medication effects) 1
• Determine if the bradycardia is persistent or intermittent 1

Management Approach

Immediate Management

• If patient is truly asymptomatic with adequate perfusion, urgent intervention may not be required, but close monitoring is essential 1
• Temporary discontinuation of rate-slowing medications may be necessary while planning definitive management 1

Definitive Management

1. Permanent Pacemaker Implantation:

   • Recommended for asymptomatic patients with HFrEF and severe bradycardia to enable optimal GDMT implementation 1
   • CRT (Cardiac Resynchronization Therapy) rather than right ventricular pacing is recommended for patients with HFrEF regardless of NYHA class who have an indication for ventricular pacing 1

2. Optimization of GDMT after pacemaker implantation:

   • Initiate or optimize the four pillars of HFrEF therapy in a stepwise manner 1, 2:
     • SGLT2 inhibitors (dapagliflozin or empagliflozin) 1
     • Beta-blockers (carvedilol, metoprolol succinate, or bisoprolol) 1
     • Mineralocorticoid receptor antagonists (spironolactone or eplerenone) 1
     • ACE inhibitors/ARBs or preferably ARNI (sacubitril/valsartan) 1

Special Considerations

• Beta-blocker initiation: Start at low doses and titrate gradually after pacemaker implantation, as the patient's bradycardia may limit beta-blocker use initially 3
• Diuretics: Use as needed for symptom relief and volume management 1
• ICD evaluation: Consider ICD implantation at the time of pacemaker placement if the patient meets criteria (LVEF ≤35% despite ≥3 months of optimal medical therapy) 1
• Monitoring: Regular follow-up to assess for symptom development, medication tolerance, and device function 1

Pitfalls to Avoid

• Delaying pacemaker implantation: Failure to address severe bradycardia may prevent optimization of life-saving GDMT 2, 4
• Withholding GDMT: Underutilization of evidence-based therapies is common in HFrEF patients and associated with worse outcomes 1, 4
• Overlooking CRT benefit: Standard right ventricular pacing may worsen ventricular dyssynchrony; CRT is preferred in HFrEF patients requiring pacing 1
• Ignoring asymptomatic status: Even without symptoms, severe bradycardia in HFrEF patients represents a high-risk condition that warrants intervention 1

Follow-up Plan

• Device check within 2-4 weeks of implantation 1
• Gradual titration of GDMT medications to target doses 2, 4
• Regular monitoring of renal function and electrolytes, particularly when initiating or titrating RAAS inhibitors and diuretics 1
• Echocardiographic assessment 3-6 months after optimizing therapy to evaluate for improvement in ejection fraction 1