The Benefit and Harm of an Implantable Cardiac Defibrillator in a Patient with Heart Failure: A Case Report and Literature Review.

Background and Clinical Significance: Infective endocarditis (IE) in patients with cardiac implantable electronic devices (CIED-IE) is a severe condition with high mortality and increasing prevalence. Case Presentation: A 50-year-old man with diabetes, idiopathic dilated cardiomyopathy, and a dual-chamber implantable cardioverter-defibrillator (ICD) for secondary prevention of sudden cardiac death (SCD) presented with fever and peripheral arthritis. Initially evaluated for rheumatic disease, IE was ruled out at an initial cardiac evaluation. A subsequent computed tomography scan revealed a renal tumor, leading to transfer to the urology department. The patient was later evaluated in our cardiology department, where transthoracic and transesophageal echocardiography identified lead vegetations. Blood cultures and serologic tests remained negative. Empirical antibiotic therapy was initiated, and percutaneous ICD lead extraction was performed, with cultures remaining negative. After six weeks of antibiotic therapy the patient had a favorable outcome, then a subcutaneous ICD (S-ICD) was implanted three months later for SCD prevention. The renal tumor required nephrectomy, confirming clear cell renal carcinoma. Conclusions: This case highlights the diagnostic and therapeutic challenges of blood culture-negative CIED-IE and underscores the importance of a multidisciplinary approach in complex cases.