Bartonellosis is a disease caused by Bartonella spp. microorganisms of the order Rickettsiales. This disease is a zoonosis. B. henselae, whose primary reservoir is the cat, causes cat-scratch disease in humans. In infected cats, bartonellosis gives rise to symptoms such as fever, lymphedema, reproductive system disorders, myocarditis, rhinotracheitis, gingivitis, and arthritis. This review presents the potential role of Bartonella microorganisms in the development of endocarditis. Clinicians should be aware that this kind of complication in cats may be associated with Bartonella spp. infection.