A 38-year-old man comes to the emergency department due to a day of progressive shortness of breath. Over the past week, he has also had fever and malaise. The patient uses intravenous heroin daily. Temperature is 39.6 C (103.3 F), blood pressure is 100/56 mm Hg, pulse is 102/min and regular, and respirations are 20/min. Oxygen saturation is 93% on room air. The patient is in moderate respiratory distress. Bibasilar crackles are heard on lung auscultation. Cardiac examination reveals a 3/6 holosystolic murmur that radiates to the left axilla. There is 1+ bilateral pedal edema. Laboratory evaluation shows a hematocrit of 33% and a leukocyte count of 19,000/mm³ with a left shift. ECG reveals sinus tachycardia. Chest x-ray reveals pulmonary edema and no cardiomegaly. Echocardiography demonstrates a 1-cm vegetation on the mitral valve and severe mitral regurgitation. Blood cultures are drawn, and empiric broad-spectrum antibiotics are initiated. Oxygen is also administered via nasal canula. What is the most appropriate next step in management?

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Explanation: 11ec25c8_d8ab_b05f_bc81_81dcb20d3835_MD0003_00 This patient who uses intravenous heroin has subacute nonspecific symptoms, fever, leukocytosis, and a mitral valve vegetation, indicating infective endocarditis (IE). His acute shortness of breath, pulmonary edema, and bilateral lower extremity edema suggests that he is in heart failure, likely due to severe mitral regurgitation from infectious destruction of the valve. Heart failure is the most common cause of death in patients with IE and most commonly occurs with infection of the aortic or mitral valves. Although patients with intravenous drug use are most likely to develop right-sided IE, isolated or concurrent infection of the left-sided heart valves frequently occurs. IE can have local (eg, valve) or systemic (eg, septic emboli) complications, and patients can deteriorate rapidly; urgent surgical intervention is indicated in those with any of the following: Heart failure from valve dysfunction (as in this patient) Localized extension of infection (eg, abscess, fistula, heart block) Difficult-to-treat pathogens (eg, fungi, multidrug-resistant organisms) Very high risk of embolism (eg, large valvular vegetation [>1 cm]) or persistent septic embolization despite appropriate antibiotic therapy (Choice A) Septic embolism is common in patients with IE. However, anticoagulation does not diminish the risk of septic embolization and may increase the risk of bleeding complications; therefore, it is not recommended. (Choice B) Patients with heart failure with reduced ejection fraction should be initiated on beta blockers (eg, metoprolol) to reduce mortality and hospitalization rates. However, beta blockers should not be started until acute volume overload has resolved. This patient is in acute heart failure with symptomatic volume overload; a beta blocker should not be initiated at this time. (Choice C) Heart failure is the leading cause of death in patients with IE and must be addressed quickly. Urgent surgical consultation is indicated. (Choice D) Radionucleotide bone scan is used to evaluate for a focus of infection in bone (eg, osteomyelitis). This patient has a clear source for his symptoms (mitral valve vegetation in the setting of injection drug use) and no localized bone complaints; a radionucleotide bone scan would not be indicated at this time. Educational objective: Heart failure is the leading cause of death in patients with infective endocarditis (IE). Surgical intervention is generally necessary for those with IE who have heart failure, local progression (eg, abscess, conduction abnormality), persistent bacteremia, large vegetations, and difficult-to-treat organisms.

A 38-Year-Old Man Comes to the Emergency Department Due to a Day