Fistula of the mitral-aortic intervalvular fibrosa in a patient with bacterial endocarditis: a case report and systematic literature review.

Background: A fistulous tract in the mitro-aortic intervalvular fibrosa (MAIVF) is a rare entity, which presents as a complication of endocarditis or surgical trauma. Generally, it is associated to a pseudoaneurysm of the MAIVF (p-MAIVF) or aortic abscesses. MAIVF fistulas could potentially lead to devastating complications and a high mortality rate. This condition is managed surgically, either by a percutaneous closure or an open surgical approach. Herein we report the complex case of a patient with a MAIVF fistula secondary to bacterial endocarditis. Further clinical deterioration was caused by severe aortic valve insufficiency and hemodynamic compromise, requiring surgical intervention.

Case Presentation: A 74-year-old male patient was admitted to a primary care center with complaints of malaise, asthenia, adynamia, hyporexia, and lower limb edema over the past eight days. His past medical history is positive for arterial hypertension and being monorenal. A transesophageal echocardiogram (TEE) was performed, exhibiting a 56% left ventricle ejection fraction (LVEF) and complicated aortic valve endocarditis. Surgical management through an open approach included vegetation resection, valve replacement, and closure of the MAIVF fistula. After completing antibiotic therapy, the patient was discharged without complications. During postoperative follow-up, the patient remained asymptomatic, and the control echocardiogram showed no signs of MAIVF fistula.4.

Conclusions: The clinical case of a patient with a MAIVF fistula secondary to endocarditis by Streptococcus Anginous was presented. The fistulous tract was not associated to p-MAIVF or aortic abscess, findings which further deteriorate the patient's condition and increase the likelihood of fatality. This case reinforces the importance of a prompt diagnosis through cardiac imaging and timely surgical closure of the defect.