A 34-year-old man sits forward on the stretcher, shivering beneath a thin blanket while sweat darkens the collar of his shirt. His fingertips are stained with nicotine, and he says the fever has “come and gone” for nearly three weeks; today, walking across the room left him breathless. A new blowing sound fills the left sternal border, but the blood pressure cuff has not yet finished cycling. The question is whether this is a prolonged viral illness—or the beginning of a catastrophe that will travel through his heart and bloodstream.

— What’s your move? Read on.

Before you read
  • When should antibiotics begin relative to blood cultures?
  • Which complications demand surgery rather than antibiotics alone?

When to Think of It

Enter endocarditis into the differential with persistent fever plus a new or changing murmur, prosthetic valve, prior endocarditis, injection drug use, indwelling vascular hardware, hemodialysis, congenital heart disease, or recent bacteremia. Also consider it with unexplained embolic stroke, vertebral pain, pulmonary septic emboli, glomerulonephritis, splenic infarct, or culture-negative sepsis.

Sick or Not Sick

Sick vs. not sick: Is there shock, acute pulmonary edema, altered mental status, persistent hypoxemia, or rapidly progressive valve dysfunction? The call that matters most is whether the patient needs immediate resuscitation and emergency cardiothoracic/infectious-disease involvement while cultures are obtained.

The First Fifteen Minutes

  • Place the patient on a monitor, obtain two large-bore IVs, check glucose, lactate, CBC/CMP, coagulation studies, urinalysis, ECG, and bedside ultrasound for ventricular function, pulmonary edema, and gross valve pathology.
  • Draw three sets of blood cultures from separate venipuncture sites before antibiotics, if this will not meaningfully delay treatment. In shock, obtain cultures rapidly and treat immediately.
  • Shock or high suspicion after cultures → vancomycin 20–25 mg/kg IV loading dose, infused according to institutional protocol, because it rapidly covers resistant gram-positive organisms; subsequent dosing requires renal function and pharmacy-guided AUC monitoring. Dose varies by weight, renal function, and local protocol—check Lexicomp, UpToDate, or institutional guidance.
  • Healthcare-associated infection, prosthetic material, or septic shock → cefepime 2 g IV, because it adds broad gram-negative and antipseudomonal coverage; adjust for renal function. For suspected prosthetic-valve infection, the definitive empiric regimen should be selected with infectious disease and local protocol.
  • Septic shock with MAP <65 after appropriate crystalloid → norepinephrine 0.05–0.1 mcg/kg/min IV infusion, titrated, because α-adrenergic vasoconstriction restores perfusion pressure while limiting tachyarrhythmia; use a proximal peripheral IV briefly if central access is not yet available.
  • Sepsis-induced hypoperfusion or hypotension → balanced crystalloid 30 mL/kg IV, reassessing after each bolus for pulmonary edema and ventricular failure; fluid expands preload, but excessive volume worsens acute regurgitant failure.
  • Acute pulmonary edema with adequate blood pressure → nitroglycerin 0.4 mg SL every 5 minutes for up to 3 doses, because venodilation lowers filling pressures; avoid if hypotensive, right-ventricular infarction is suspected, or recent PDE-5 inhibitor use.
  • Do not give empiric anticoagulation simply for embolic risk; intracranial hemorrhage, mycotic aneurysm, and septic embolic stroke may make it dangerous.

Definitive Care & Disposition

Admit suspected endocarditis with IV antibiotics, serial cultures, and transthoracic echocardiography; obtain transesophageal echocardiography if TTE is negative or inadequate and suspicion remains high, or with prosthetic valves, intracardiac devices, or persistent bacteremia. Tailor therapy to cultures and susceptibility testing, typically for 4–6 weeks. Urgent surgery is considered for heart failure from valve dysfunction, uncontrolled infection/abscess or prosthetic dehiscence, persistent bacteremia, fungal or highly resistant infection, and selected large mobile vegetations with recurrent emboli. ICU care is appropriate for shock, respiratory failure, acute valve regurgitation, major embolic complications, or invasive monitoring needs.

How This One Kills

The lethal miss is calling the murmur “sepsis-related” while acute valve destruction causes pulmonary edema and cardiogenic shock; more fluid and delayed echocardiography can worsen the patient instead of fixing the obstruction or regurgitation.
The Differential — What Else Looks Like This
  • Community-acquired pneumonia — focal infiltrate and respiratory symptoms without persistent bacteremia or embolic phenomena; confusing them can delay echocardiography and prolonged therapy.
  • Systemic lupus erythematosus/nonbacterial thrombotic endocarditis — sterile cultures and autoimmune or malignancy clues; antibiotics alone will not treat the underlying process.
  • Atrial myxoma — positional symptoms and constitutional illness with an intracardiac mass; mistaking it for vegetation delays surgical evaluation.
  • Septic thrombophlebitis — bacteremia with a demonstrable infected venous focus but no valve vegetation; treating only as endocarditis can miss necessary source control.

The Second-Day Story

Older adults may have no fever, presenting with delirium, weakness, weight loss, anemia, or new heart failure. Prior antibiotics may sterilize cultures, and prosthetic valves may obscure murmurs while creating perivalvular abscesses or conduction abnormalities. Persistently unexplained inflammation, embolic findings, new AV block, or recurrent bacteremia should keep the diagnosis alive and prompt TEE and infectious-disease consultation.
Back to Our Patient
Back to our 34-year-old man: persistent fever, a new murmur, dyspnea, and likely injection-drug exposure make endocarditis a high-priority diagnosis, while the blood-pressure trend and lung examination determine whether he is sick. Three blood-culture sets are drawn immediately, bedside ultrasound assesses ventricular function and pulmonary edema, and because he is hypotensive with suspected severe infection, empiric vancomycin plus cefepime is started without waiting for results; norepinephrine follows if pressure remains low after cautious crystalloid. Echocardiography is expedited, with TEE if TTE is nondiagnostic, and cardiology, infectious disease, and cardiothoracic surgery are contacted for possible acute valve destruction. He is admitted to the ICU for suspected complicated endocarditis and evolving shock.
Patient Presentation to Attending
How you’d present this patient on the floor — tight, pertinent positives and negatives, no rambling
“This is a 34-year-old man with three weeks of intermittent fever and new exertional dyspnea, now hypotensive and rigoring in the ED. He reports prior injection drug use and has no known immunosuppression or recent respiratory illness; he denies chest pain but has mild pleuritic discomfort. Exam shows a new blowing holosystolic murmur, tachycardia, cool extremities, and bibasilar crackles without focal neurologic deficit. Lactate is elevated, and bedside ultrasound suggests reduced LV function with possible mitral regurgitation. My assessment is suspected complicated infective endocarditis with early septic and possibly cardiogenic shock. We are drawing three blood-culture sets, starting empiric IV vancomycin and cefepime, using cautious crystalloid and norepinephrine as needed, obtaining urgent echocardiography, and admitting him to the ICU with infectious disease and cardiothoracic surgery consultation.”

Study Directive

  • From memory, list the major risk factors, Duke diagnostic elements, and surgical indications for infective endocarditis.
  • Practice interpreting three blood-culture collection sites and decide when TTE must be followed by TEE.
  • Draw a one-page algorithm for fever plus murmur: cultures, empiric coverage, shock treatment, echo, and disposition.
  • Review local antibiogram-based empiric regimens and verify vancomycin dosing/monitoring in Lexicomp or your institutional protocol.
  • Complete 10 board-style questions emphasizing prosthetic-valve infection, culture-negative disease, embolic complications, and periannular abscess.

Recent Literature

  • Review or guideline Infective endocarditis
    Li M, Kim JB, Sastry BKS, et al. · Lancet, 2024 · PMID 39067905 · cited 140×
    A current, authoritative overview of infective endocarditis covering diagnostic blood-culture and echocardiography strategies, antimicrobial treatment, and recognition of complications requiring urgent surgical consultation.