Regression of lupus endocarditis after treatment of an arteriovenous fistula

A young woman with systemic lupus erythematosus (SLE) and antiphospholipid antibodies was referred to our Cardiology Department. She had a large vegetation on the mitral valve, along with significant mitral regurgitation, pulmonary hypertension and slight signs of heart failure on physical examination and chest X-ray. A previously undetected iatrogenic arteriovenous fistula was surgically corrected, with subsequent normalization of pulmonary arterial pressure. Surprisingly, the mitral valve recovered a normal appearance in 21 days. We interpret the hemodynamic disturbances as a consequence of the high-output situation created by the fistula, and the regression of the vegetation as the lysis of a thrombus versus a silent embolism.