Complex surgical management of right-sided infective endocarditis following ventricular septal defect closure with residual shunt and ascending aortic pseudoaneurysm: a case report

Abstract

Introduction and importance: Right-sided infective endocarditis is an uncommon condition, especially in patients with surgically repaired congenital heart disease. A residual shunt after ventricular septal defect closure can act as a substrate for late-onset infection, but such cases are rarely reported. High-velocity jet flow from a residual shunt may contribute to endothelial injury and subsequent infection. Furthermore, differentiating a late pseudoaneurysm at a prior cannulation site from an infectious aortic aneurysm is essential for guiding the appropriate treatment strategy. Case presentation: A 49-year-old man with a history of ventricular septal defect closure in infancy presented with persistent fever and severe systemic inflammation. Transesophageal echocardiography demonstrated a highly mobile, filamentous vegetation measuring 12 × 56 mm attached to the tricuspid subvalvular apparatus. Contrast-enhanced computed tomography revealed multiple septic pulmonary emboli and a saccular protrusion along the anterior wall of the ascending aorta, suggestive of an ascending aortic pseudoaneurysm. Blood cultures yielded methicillin-susceptible Staphylococcus aureus. Following clinical improvement and multiorgan stabilization with targeted antimicrobial therapy, the patient underwent elective surgery on hospital day 49, including residual defect closure, tricuspid valve replacement with a mechanical prosthesis, and localized pseudoaneurysm repair using a Hemashield patch. Clinical discussion: This complex combination of pathologies highlights the pathophysiological impact of residual shunt-jet lesions. The clinical decision-making illustrates the challenges of balancing guideline recommendations for early surgery with the need for clinical stabilization. Conclusion: This case highlights the importance of lifelong follow-up in adult congenital heart disease and provides important considerations for individualized surgical planning in complex cardiovascular pathologies.