A 68-year-old man presents to the emergency department with worsening shortness of breath … — USMLE Step 3

A 68-year-old man presents to the emergency department with worsening shortness of breath on exertion, orthopnea, and lower extremity edema over the past $3$ weeks. He has a history of hypertension, type 2 diabetes mellitus, and paroxysmal atrial fibrillation. Two years ago, an echocardiogram demonstrated a normal left ventricular ejection fraction (LVEF) of $55\%$ .

His current home medications include:
- Flecainide $50$ mg twice daily
- Diltiazem CD $240$ mg daily
- Metformin $1000$ mg twice daily
- Apixaban $5$ mg twice daily

Vital signs:
- Blood pressure: $118/74$ mmHg
- Heart rate: $88$ /min (irregularly irregular)
- Respiratory rate: $22$ /min
- Oxygen saturation: $92\%$ on room air

Physical examination reveals elevated jugular venous pressure to $12$ cm $H_2O$ , bibasilar lung crackles, and $2+$ pitting edema of the lower extremities up to the knees. The extremities are warm and well-perfused.
An electrocardiogram confirms atrial fibrillation with a ventricular rate of $88$ /min and no acute ischemic changes.
A point-of-care echocardiogram reveals a newly reduced LVEF of $25\%$ with global hypokinesis.

Laboratory studies:
- Serum creatinine: $1.8$ mg/dL (baseline $1.1$ mg/dL)
- Blood urea nitrogen: $38$ mg/dL
- Serum potassium: $4.2$ mEq/L
- NT-proBNP: $4,500$ pg/mL (normal: $<125$ pg/mL)

Based on these findings, which of the following pharmacologic interventions are indicated in the immediate management of this patient? (Select all that apply)

Discontinue flecainideCevap
Discontinue diltiazemCevap
Initiate intravenous furosemideCevap
D
Initiate oral metoprolol succinate
E
Administer an intravenous normal saline bolus

Cevap

The correct interventions are to discontinue flecainide, discontinue diltiazem, and initiate intravenous furosemide.

The correct interventions address the acute volume overload while removing medications that exacerbate heart failure with reduced ejection fraction (HFrEF). The option to initiate intravenous furosemide is correct because loop diuretics are the first-line therapy for acute decompensated heart failure to relieve pulmonary and systemic congestion. The option to discontinue flecainide is correct because it is a Class IC antiarrhythmic with negative inotropic effects, strictly contraindicated in structural heart disease due to an increased risk of lethal proarrhythmia. The option to discontinue diltiazem is correct as it is a non-dihydropyridine calcium channel blocker possessing potent negative inotropic properties, which exacerbates HFrEF and increases mortality.

Adım Adım Çözüm

Identify the patient's hemodynamic profile and new diagnosis.

The patient has acute decompensated heart failure ('warm and wet' profile) with a newly reduced LVEF of 25%.

Accurate profiling is essential to guide immediate pharmacologic management and avoid harmful interventions.

Review the patient's home medication list for contraindications.

Flecainide and diltiazem are identified as strictly contraindicated.

Both medications possess strong negative inotropic properties that exacerbate HFrEF and increase mortality.

Determine the appropriate treatment for the patient's volume overload and acute kidney injury.

Intravenous furosemide is selected as the primary intervention.

The acute kidney injury is due to cardiorenal syndrome (venous congestion). Diuresis relieves congestion and typically improves renal function, whereas fluids would be detrimental.

Evaluate the safety of initiating new guideline-directed medical therapies.

Initiation of beta-blockers (e.g., metoprolol succinate) is deferred.

Starting beta-blockers in a significantly volume-overloaded, acutely decompensated patient can precipitate cardiogenic shock and must wait until euvolemia is achieved.

Anahtar Kavram

In patients newly diagnosed with heart failure with reduced ejection fraction (HFrEF) presenting with acute decompensation, negatively inotropic medications (e.g., Class IC antiarrhythmics, non-dihydropyridine CCBs) must be immediately discontinued, and diuresis should be initiated to treat cardiorenal syndrome while withholding beta-blocker initiation until euvolemia is achieved.

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