Infective Endocarditis

Evolving trends in infective endocarditis

Infective endocarditis is a microbial infection of the endocardial surface and, despite improvements in diagnostic accuracy, medical therapy and surgical techniques, mortality remains high. This review focuses on changes in epidemiology, microbiology and diagnosis, as well as changes in medical and surgical management of infective endocarditis affecting native and prosthetic valves in adults, that have evolved during the past two decades. Significant changes have included an increasing involvement of prosthetic valves and nosocomially-acquired disease, an increased involvement of staphylococci as the causative agents, and a recognition that elderly individuals with degenerative valvular disease are the most vulnerable population. Topics still requiring study include whether and when valve replacement should be performed, and how to predict perivalvular complications or embolisation based on echocardiography findings. Optimisation of antimicrobial treatment schemes (choice of the antibiotic, dose and duration) also requires further investigation.

Infective endocarditis in the elderly: diagnosis and management

Infective endocarditis is seen with increasing frequency in older patients. This increase is due to the general aging of the population, improved survival of patients with congenital and valvular heart disease, and the increasing use of catheters and other prosthetic devices with resulting higher incidence of nosocomial endocarditis. In older patients, infective endocarditis frequently develops in the absence of underlying structural heart disease; atheromatous deposits and mitral annular calcification are two important risk factors in this population. Infective organisms in older patients are frequently enterococci and other gastrointestinal tract bacteria. A marked febrile response is uncommon whereas central nervous system symptoms are more common in older patients. Transesophageal echocardiography can be performed safely and is a major diagnostic tool with sensitivity of more than 90% in detecting vegetations as small as 2-5 mm. Appropriately drawn blood cultures provide bacteriologic diagnosis in 80%-99% of patients. Prolonged antibiotic therapy may be required in many instances depending on the infective organism. Early surgical therapy is advisable for patients who develop heart failure as a result of severe acute aortic valvular regurgitation. Valve replacement surgery can be performed with acceptable mortality and morbidity even in very elderly patients.

Infective endocarditis and the dental practitioner

This article reviews the relationship of dental treatment to infective endocarditis (IE). The current guidelines on the use of antibiotics in prophylaxis are also examined.