Left Atrial Mural Endocarditis : Diagnosis by Transesophageal Echocardiography

Left Atrial Mural Endocarditis: Diagnosis by Transesophageal Echocardiography PEDRO GUTIERREZ-FAJARDO, M.D., NILDA ESPINOLA-ZAVALETA, M.D., ANGEL ROMERO-ChDENAS, M.D., LUIS REYES-NAVARRO, M.D., CANDACE KEIRNS, M.D., and JESUS VARGAS BARRON, M.D. Department of Echocardiography, Instituto Nacional de Cardiologia “Ignacio Chavez”, Mexico City, Mexico

Case Report The patient was a 36-year-old woman with a history of rheumatic fever in childhood. She was asymptomatic until 6 months before, when she experienced dyspnea, orthopnea, and occasional paroxysmal nocturnal fever. A month later, she noted arthritis and arthralgia in both knees and ankles, malaise, and hyporexia. Her physical examination revealed a hyperdynamic precordium with a holosystolic murmur of grade IIM at the lowest point on the left sternal border radiating to the left axilla. A diastolic rumble was also heard over the apex of the heart with a loud P2 and S3 gallop. On legs

and feet purpuric lesions could be observed. Venous blood cultures grew out s. viridans. A transthoracic echocardiogram was performed that demonstrated rheumatic mitral disease with thickened leaflets. On the posterior leaflet several vegetations were observed. Severe mitral regurgitation was documented as well as mild thickening and regurgitation of the tricuspid valve. Four days later transesophageal echocardiography (TEE) was performed, which confirmed the findings by transthoracic echocardiography (TTE) and in addition showed vegetations on both the anterior valve leaflet (Fig. 1A) and the left atrial wall (Fig. 1B). Rupture of a tertiary chorda tendinea

Figure 1. (A) Transesophageal view in transverse plane showing vegetations on anterior valve leaflet (arrow). (B) Vegetations on left atrial wall (arrow). LV = left ventricle; LAA = lefl atrial appendage. Address for correspondence and reprints: Jesus VargasBarron, M.D., Department of Echocardiography, Calle Juan Badiano n4 1, Colonia Seccion XVI, Tlalpan-14080, Mexico City, Mexico. Fax: 573-0994.

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Figure 2. Transesophageal approach in longitudinal plane. Rupture of a tertiary chorda tendinea of mitral apparatus is observed (arrow). LA = left atrium.

Figure 3. Transesophageal image i n transverse plane. Interatrial septal aneurysm is shown. L A = left atrium; LV = left ventricle; RV = right ventricle.

of the mitral apparatus (Fig. 2) and an interatrial septal aneurysm (Fig. 3) were also found. Color-coded Doppler demonstrated severe mitral regurgitations. Vegetations on posterior and anterior mitral leaflets and on the left atrial wall as well as a detachment of the anterior valve leaflet were confirmed during surgery 3 days later.

with variable destructive effects.’ Less common is isolated primary mural endocarditis seen in chronically ill or immunosuppressed patients without cardiac disease.2 To our knowledge, there are 25 reported cases of mural endocarditis. Six of them were demonstrated by transthoracic two-dimensional echocardiography and confirmed by transesophageal technique performed to determine the location and size of vegetations on the posterior wall of the left atrium.’

Discussion Mural vegetations are thought to occur in two ways. The most common involves growth of a vegetation at the site of a jet lesion, that is, the impact site of a regurgitation jet or stream, with dissemination of an infecting microorganism in a retrograde fashion. The microorganism in this regurgitant jet will invade the mitral valve, in cases of previous mitral damage,

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References 1. Gonzalez LL, Lise M, Ross D: The importance of “jet lesion” in bacterial endocarditis involving the left heart. Surgical considerations. J Thorac Cardiouasc Surg 1970;59:185-192. 2. Walsh TJ, Hutchins GM. Aspergillus mural endocarditis. J Clin Pathol 1979;7:640-644.

ECHOCARDIOGRAPHY: A Jrnl. of CV Ultrasound & AUied Tech.

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