Louisiana Research Day Program Book 2025

Case Studies: Section 2

119 BEYOND THE HEARTBEAT: A RARE AORTOPULMONARY FISTULA IN CULTURE-NEGATIVE ENDOCARDITIS

Sham Kumar, MD¹, Binod Mehta, MD¹, Kavita Shah, MD¹, Madison Courville, OMS-III², Nisheem Pokharel, MD¹, Harikrishna Bandla, MD¹. ¹St. Francis Medical Center, Monroe, Louisiana; ² VCOM-Louisiana

Background: Aortopulmonary fistula, a rare and life-threatening condition, involves an abnormal connection between the aorta and pulmonary artery, disrupting cardiovascular physiology. While most cases result from aneurysm erosion, we present a unique case caused by an aortic root abscess associated with culture-negative endocarditis. Case Presentation: A 58-year-old female with a history of bioprosthetic mitral and aortic valve replacements, thoracic and abdominal aortic aneurysms, ischemic cardiomyopathy, prior pulmonary embolism, and two CVAs presented with worsening dyspnea, orthopnea, and fatigue. She had recently completed treatment for culture negative endocarditis, diagnosed after a transesophageal echocardiogram (TEE) revealed a large vegetation (1.05 cm) on the aortic valve 8 weeks prior. During her prior admission, extensive workup, including IgG, IgG4, vasculitis panel, antiphospholipid panel, hepatitis panel, syphilis testing, and complement levels, was unremarkable. Inflammatory markers, including ESR and CRP, were normal or trending down.

Rheumatology favored an infectious etiology, recommending against immunosuppressive therapy. Despite six weeks of antibiotics, she now presented with AKI, lactic acidosis, and cardiogenic shock. Examination revealed hypotension, tachycardia, distended neck veins, and a diastolic murmur. A transthoracic echocardiogram performed on admission revealed a degenerative bioprosthetic aortic valve, a ruptured aortic root abscess, and a high-flow aortopulmonary fistula. A TEE performed two weeks prior showed severe aortic regurgitation, left ventricular dysfunction (EF 25-30%), and a large vegetation extending into the annulus. Despite these findings, extensive comorbidities and recent CVAs led cardiothoracic surgery to deem her a poor surgical candidate. Cardiology recommended transfer to a tertiary center, but the patient’s family declined, opting for medical management with inotropic support and diuretics. Blood cultures remained negative, and no additional antibiotics were initiated. The infectious disease team concurred with no further antibiotics. Her guarded prognosis was discussed with her husband, who chose to maintain full code status.

Conclusion: Culture-negative endocarditis presents diagnostic and therapeutic challenges, with rare complications such as aortopulmonary fistulas requiring prompt recognition. This case highlights the progression of endocarditis into an aortic root abscess and subsequent fistula, underscoring the importance of individualized, multidisciplinary care and effective communication with families.

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135 2025 Research Recognition Day