The risk factors for cardiovascular (CV) infections are related to the immunocompetence of the host, preexisting cardiac conditions, and exposure to infectious organisms. Immunocompromised states are related to defective physical and chemical barriers and/or alterations of immune organs, cells, and substances. There are many conditions, diseases, drugs, and therapies that are associated with immunocompromised states. In-dwelling central venous catheters, prosthetic valves/devices, cardiac lesions, and conditions that create turbulent blood flow increase risk for CV infections. An understanding of the immune response, risk factors for immunocompromise, and risk factors for CV infections helps guide the CV nurse's plan of care related to assessment and interventions for prevention, identification, and treatment of CV infections. Diagnosis, monitoring, and management challenges of the immunocompromised patient with infective endocarditis and myocarditis are presented.