External left atrium compression by spinal osteophytes: LANC
A previously healthy 76-year-old woman was assessed preoperatively prior to hip arthroplasty. Cardiac examination was notable for a mid-diastolic murmur at the apex—appreciable only in the supine position. She had no signs or symptoms of heart failure.

The patient's N-terminal-pro-B-type natriuretic peptide blood concentration was normal (71 pg/mL). A transthoracic echocardiogram showed preserved biventricular systolic function, unimpaired diastolic relaxation, normal left atrial dimensions free of any intra-atrial septation, and no valvular abnormalities.

However, both apical four-chamber and short-axis views revealed evidence of extrinsic compression of the left atrium. A subsequent CT scan identified large, beaked, osseous outgrowths from the thoracic spinal bodies T7 to T10 that were directly compressing the heart's left atrium. No intervention was recommended in view of the patient's asymptomatic clinical status and she was medically cleared for the orthopaedic surgery.

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