Sinus of Valsalva aneurysms may occur with rupture into any of the cardiac chambers.140 Clinical signs and symptoms of extension of infection beyond valve leaflets are nonspe- cific and include persistent bacteremia or fever, recurrent emboli, heart block, worsening congestive heart failure, or new pathological murmurs in patients receiving appropriate Surgicallycreatedshuntsorintracardiacconduitsareapoten- tial source for complications of IE. Because these connections Table 8. Empirical Therapy in Culture-Negative Endocarditis* Regimen Dosage and Route Duration, wk Strength of Recommendation (Class/LOE) Comments Native valve Ampicillin-sulbactam 12 g/d IV in 4 equally divided doses 4 6 IIb/C Consensus of experts is that patients with culture-negative endocarditis should be managed with consultation with an infectious diseases specialist plus IV/IM in 3 equally divided doses 4 6 IV in 2 equally divided doses 4 6 IIb/C Vancomycin is recommended only for patients who are unable to tolerate penicillins plus IV/IM in 3 equally divided doses 4 6 plus ciprofloxacin 1500 mg/d PO or 800 mg/d IV in 2 equally divided doses Pediatric dosage: Ampicillin-sulbactam 300 IV in 4 6 equally divided doses; IV/IM in 3 equally divided doses; vancomycin 40 mg kg 1 or 3 equally divided doses; ciprofloxacin 20 30 IV/PO in 2 equally divided doses Prosthetic valve (early, 1 y) IV in 2 equally divided doses 6 IIb/C plus IV/IM in 3 equally divided doses 2 plus cefepime 6 g/d IV in 3 equally divided doses 6 plus rifampin 900 mg/d PO/IV in 3 equally divided doses 6 Pediatric dosage: Vancomycin 40 mg kg 1 IV in 2 or 3 equally divided doses; gentamicin IV/IM in 3 equally divided doses; IV in 3 equally divided PO/IV in 3 equally divided doses Prosthetic valve (late, >1 y) 6 IIb/C Same regimens as listed above for native valve endocarditis Suspected Bartonella, culture negative Ceftriaxone sodium 2 g/d IV/IM in 1 dose 6 IIa/B Patients with Bartonella endocarditis should be treated in consultation with an infectious diseases specialist plus IV/IM in 3 equally divided doses 2 with or without doxycycline 200 mg/d IV/PO in 2 equally divided doses 6 (Continued) Baltimore et al Infective Endocarditis in Childhood: 2015 Update 1507 involve various prosthetic materials, including Gore-Tex, Dacron, or homografts, bacteriologic cure is often impossible without surgical intervention. 