A 53-year-old man comes to the emergency department due to fever and progressive weakness over the last 2 weeks. Yesterday, he also developed shortness of breath. The patient emigrated from Eastern Europe 2 years ago and says he was diagnosed with "heart disease" in the distant past, but he does not recall any details. He does not use tobacco, alcohol, or illicit drugs. Despite receiving appropriate medical care, the patient expires during hospitalization. On autopsy, gross examination of his heart shows large, friable masses on the mitral valve with extensive destruction of cuspal tissue. Which of the following is the most likely predisposing factor for this patient's presenting condition?

Question

A 53-year-old man comes to the emergency department due to fever and progressive weakness over the last 2 weeks.  Yesterday, he also developed shortness of breath.  The patient emigrated from Eastern Europe 2 years ago and says he was diagnosed with "heart disease" in the distant past, but he does not recall any details.  He does not use tobacco, alcohol, or illicit drugs.  Despite receiving appropriate medical care, the patient expires during hospitalization.  On autopsy, gross examination of his heart shows large, friable masses on the mitral valve with extensive destruction of cuspal tissue. Which of the following is the most likely predisposing factor for this patient's presenting condition?

Quizplus · Accepted Answer

This patient's presentation - fever, progressive weakness, and dyspnea (due to valvular regurgitation) - along with the presence of vegetations on the mitral valve is consistent with infective endocarditis (IE). Predisposing factors for IE include valvular abnormalities (eg, rheumatic heart disease, mitral valve prolapse, prosthetic valves, congenital heart disease) and conditions that promote bacteremia/fungemia (eg, intravenous drug use, dental procedures). This patient likely had a remote history of rheumatic heart disease (immigrant from developing region, history of heart disease) with underlying degeneration of the mitral valve due to chronic valvular inflammation and scarring. (Choice A) Myocardial hypertrophy is seen in patients with uncontrolled hypertension, aortic stenosis, and hypertrophic cardiomyopathy and, in general, does not predispose to IE. (Choice B) Myocardial fibrosis is associated with infiltrative cardiomyopathy (sarcoidosis, amyloidosis), Chagas disease, myocarditis, and prior myocardial infarction. It does not lead to increased risk of IE. (Choice C) Pericardial effusion occurs as a result of inflammation of the pericardium (acute or chronic pericarditis) and has no association with the risk of IE. (Choice D) Rupture of chordae tendineae is a complication of endocarditis or myocardial infarction; it is not a risk factor for development of IE. Educational objective: Chronic valvular inflammation and scarring associated with rheumatic heart disease predispose to an increased risk of infective endocarditis, which is characterized by valvular vegetations with destruction of the underlying cardiac tissue. __________ References: Underlying cardiac lesions in adults with infective endocarditis. The changing spectrum. (http://www.ncbi.nlm.nih.gov/pubmed/3565426)

A 53-Year-Old Man Comes to the Emergency Department Due to Fever