A 54-year-old man presents to the emergency department with worsening shortness of breath for 3 days. Two weeks ago, he was admitted to the hospital with infective endocarditis involving the aortic valve caused by methicillin-sensitive Staphylococcus aureus. He was discharged home with a peripherally inserted central catheter to complete a 6-week course of intravenous cefazolin. Since discharge, he initially felt better. However, over the past several days he has developed progressive dyspnea, orthopnea, and profound fatigue. He denies chest pain. His medical history is significant for hypertension and type 2 diabetes mellitus. Temperature is 38.0°C (100.4°F), blood pressure is 118/42 mm Hg, pulse is 112/min, respiratory rate is 26/min, and oxygen saturation is 91% on room air. Physical examination demonstrates respiratory distress. Jugular venous pressure is mildly elevated. Diffuse crackles are present throughout both lung fields. Cardiac examination reveals a new high-pitched early diastolic decrescendo murmur along the left sternal border. Peripheral pulses are bounding.
Laboratory studies show the following:
Repeat transthoracic echocardiography demonstrates the following:
Large mobile vegetation on the aortic valve
Severe aortic regurgitation
Left ventricular ejection fraction: 55%
Which of the following is the most appropriate next step in management?
The correct answer is:
B) Emergent surgical valve replacement
This patient has infective endocarditis complicated by acute severe aortic regurgitation causing heart failure. The key clues are worsening dyspnea, pulmonary edema, a new diastolic murmur, a widened pulse pressure, and echocardiographic evidence of severe aortic valve destruction.
Acute aortic regurgitation is a medical and surgical emergency. Unlike chronic aortic regurgitation, the left ventricle has not had time to adapt to the sudden increase in regurgitant volume. As blood rapidly flows back into the left ventricle during diastole, left ventricular end-diastolic pressure rises abruptly, causing pulmonary edema and reduced forward cardiac output.
In infective endocarditis, the development of acute valvular dysfunction with heart failure is one of the strongest indications for urgent surgical intervention. Antibiotics alone are unlikely to reverse the hemodynamic consequences of severe valve destruction.
A high-yield Step 2 principle is that surgery is often required for infective endocarditis when complications develop, particularly:
Acute heart failure due to valvular dysfunction
Perivalvular abscess formation
Persistent bacteremia despite therapy
Recurrent embolic events from large vegetations
Answer choice A: Continue current antibiotic therapy and repeat echocardiography in 6 weeks, is incorrect.
Medical therapy alone is insufficient once severe valvular dysfunction has caused heart failure. Delaying intervention would place the patient at high risk for cardiogenic shock and death.
Answer choice C: Initiate intravenous diltiazem for afterload reduction, is incorrect.
Diltiazem is not appropriate treatment for acute severe aortic regurgitation and may worsen hemodynamics through negative inotropic effects. The primary problem is structural destruction of the aortic valve.
Answer choice D: Perform electrical cardioversion, is incorrect.
There is no evidence that an arrhythmia is causing this patient’s deterioration. The underlying problem is acute severe valvular insufficiency and pulmonary edema.
Answer choice E: Transition to oral antibiotics and outpatient follow-up, is incorrect.
This patient has developed a life-threatening complication of endocarditis requiring urgent inpatient management and surgical evaluation. Outpatient therapy would be unsafe.
Key Learning Point
Acute heart failure caused by infective endocarditis–related valve destruction is a major indication for urgent surgical intervention. Acute severe aortic regurgitation often presents with pulmonary edema, widened pulse pressure, and rapid clinical deterioration.
