Nonvalvular infections of the cardiovascular system.

PURPOSE: To review the risk factors, clinical presentation, diagnosis, and treatment of nonvalvular infections of the cardiovascular system. DATA SOURCES: A MEDLINE search of English-language articles from 1966 to 1993 relating to myocardial abscesses, mural endocarditis, infective endarteritis and mycotic aneurysms, infection of pacemakers and implantable defibrillators, prosthetic vascular graft infections, and infected atrial myxomas; manual review of article bibliographies. STUDY SELECTION AND DATA EXTRACTION: Case series and single reports, prospective and retrospective clinical studies, autopsy studies, and reviews were selected if they contained sufficient information about the prevalence, clinical manifestations, microbiologic features, management, and outcome of nonvalvular cardiovascular infections.
RESULTS: Nonvalvular infections of the cardiovascular system most commonly occur on previously damaged endocardium or vascular intima and are usually associated with intravascular devices such as graft material or pacemakers. Rarely, they can involve primary cardiac tumors such as myxomas. Most patients affected are beyond the fifth decade of life. Risk factors include cardiovascular disease, diabetes mellitus, and malignancy. The sexes are affected equally. The clinical presentations of nonvalvular endovascular infections are subtle and diagnoses are difficult to make, often requiring not only a high index of suspicion but also the use of sophisticated radiologic techniques. Hence, for many of these infections, the diagnosis is made late in the course of the infection, and survival rates are poor. Complications include peripheral embolization, cardiac rupture, vascular aneurysm rupture, and pericarditis. Therapy frequently involves surgical intervention in addition to the use of antibiotics.
CONCLUSIONS: Although uncommon, nonvalvular infections of the cardiovascular system will increase in frequency as the use of implantable devices and prosthetic materials increases in the elderly. Studies are needed to determine the most appropriate diagnostic methods, treatment regimens, and methods for prevention of these infections.