What should the cardiologist do for a 67-year-old female with hypertension, atrial fibrillation (a fib) on Eliquis (apixaban), peripheral vascular disease, and type 2 diabetes, presenting with palpitations, chest pain, and elevated B-type natriuretic peptide (BNP), who was recently treated with IV Lasix (furosemide) in the ED?

Management of a 67-Year-Old Female with Atrial Fibrillation, Elevated BNP, and Recent ED Visit

The cardiologist should perform a comprehensive cardiac evaluation focusing on heart failure assessment, as the markedly elevated BNP of 2500 pg/mL strongly suggests heart failure with atrial fibrillation with rapid ventricular response (AFib with RVR) as the precipitating factor. 1, 2

Initial Assessment

Cardiac Structure and Function Evaluation

• Echocardiography to assess:
  • Left ventricular ejection fraction (LVEF)
  • Chamber geometry and regional wall motion
  • Valve function (particularly mitral and tricuspid)
  • Diastolic function parameters
  • Signs of right ventricular dysfunction
  • Presence of left atrial enlargement

Rate Control Assessment

• Evaluate adequacy of current rate control medications
• Determine if patient's AFib with RVR is adequately controlled on current Eliquis (apixaban) regimen
• Check apixaban dosing based on age, weight, and renal function 3

Volume Status Evaluation

• Assess for signs of congestion:
  • Jugular venous distention
  • Pulmonary crackles
  • Peripheral edema
  • Hepatomegaly
  • S3 gallop

Diagnostic Workup

Laboratory Tests

• Serial BNP measurements to track response to therapy 1, 4
  • The markedly elevated BNP (2500 pg/mL) is a strong predictor of both short and long-term mortality
  • Follow-up measurements help identify patients at risk for readmission or death
• Complete metabolic panel with renal function
• Thyroid function tests
• Electrolytes (particularly potassium and magnesium levels)
• Hemoglobin A1c (given history of diabetes)

Additional Testing

• 12-lead ECG to assess rhythm and rate
• Consider stress testing if ischemia is suspected as a contributor
• Consider coronary angiography if high suspicion for coronary artery disease

Treatment Approach

Heart Failure Management

1. Optimize volume status:

   • Adjust diuretic therapy based on response to IV Lasix given in ED
   • Consider higher doses of loop diuretics if diuretic resistance is present 1

2. Guideline-directed medical therapy for heart failure:

   • ACE inhibitor or ARB (if not already prescribed)
   • Beta-blocker (carefully titrated given AFib)
   • Mineralocorticoid receptor antagonist (e.g., spironolactone) 1
   • Consider ARNI (sacubitril/valsartan) if LVEF is reduced 2

Atrial Fibrillation Management

1. Rate control strategy:

   • Optimize beta-blocker dosing
   • Consider adding calcium channel blocker or digoxin if needed

2. Anticoagulation:

   • Continue Eliquis (apixaban) with appropriate dosing based on age, weight, and renal function
   • Ensure proper dosing: 5mg BID standard dose; 2.5mg BID if ≥2 of: age ≥80, weight ≤60kg, or creatinine ≥1.5mg/dL 3

3. Rhythm control consideration:

   • Evaluate if rhythm control strategy would benefit the patient
   • Consider cardioversion if symptoms persist despite rate control

Comorbidity Management

• Optimize diabetes management
• Assess and treat peripheral vascular disease
• Ensure hypertension is well-controlled

Monitoring and Follow-up

Short-term Monitoring

• Rhythm monitoring for 24 hours or longer if at increased risk for cardiac arrhythmias 1
• Daily weights to assess fluid status
• Electrolyte monitoring, especially if diuretic therapy is intensified

Long-term Follow-up

• Serial BNP measurements to track response to therapy
  • A reduction of >30% indicates good response 2, 4
  • Persistently elevated BNP despite therapy indicates higher risk for readmission or death 4
• Regular assessment of renal function
• Medication adjustment based on clinical response

Important Considerations

• BNP interpretation caveats: A single BNP measurement may not perfectly reflect the degree of congestion; clinical assessment remains crucial 5
• Diuretic response: Monitor for diuretic resistance, which may require combination diuretic therapy 1
• Anticoagulation management: Ensure proper dosing of apixaban based on patient characteristics 3
• Comorbidity impact: Diabetes, hypertension, and peripheral vascular disease can all worsen heart failure outcomes and require optimization 2

By following this structured approach, the cardiologist can effectively manage this patient's acute presentation of atrial fibrillation with rapid ventricular response and elevated BNP, likely representing heart failure exacerbation.