Cardiobacterium hominis is an uncommon cause of prosthetic valve endocarditis (PVE) and often presents insidiously. In comparison, prosthetic valve thrombosis (PVT) is a rare, but life-threatening condition that commonly occurs due to inadequate anticoagulation. Anticoagulation is relatively contraindicated in patients with endocarditis as it may prove to be lethal due to increased risk of cerebral hemorrhage. However, anticoagulation is required in patients with PVT, or for its prevention. We present a case of a 35-year-old male with a history of hypercoagulability and St. Jude's aortic valve on warfarin, who presented with chest pain andwas found to have a mass on the aorticvalve, with blood cultures revealing C. hominis.The patient was treated with appropriate antibiotics and anticoagulation was continued. No neurological complications were noted during the treatment period. This case demonstrates that carefully weighing the risks and benefits of continuing anticoagulation is essential in preventing poor outcomes.