Challenges in Infective Endocarditis

Thomas J. Cahill, MBBS; Larry M. Baddour, MD; Gilbert Habib, MD; Bruno Hoen, MD, PHD; Erwan Salaun, MD; Gosta B. Pettersson, MD, PHD; Hans Joachim Schäfers, MD; Bernard D. Prendergast, DM


J Am Coll Cardiol. 2017;69(3):325-344. 

In This Article

Abstract and Introduction


Infective endocarditis is defined by a focus of infection within the heart and is a feared disease across the field of cardiology. It is frequently acquired in the health care setting, and more than one-half of cases now occur in patients without known heart disease. Despite optimal care, mortality approaches 30% at 1 year. The challenges posed by infective endocarditis are significant. It is heterogeneous in etiology, clinical manifestations, and course. Staphylococcus aureus, which has become the predominant causative organism in the developed world, leads to an aggressive form of the disease, often in vulnerable or elderly patient populations. There is a lack of research infrastructure and funding, with few randomized controlled trials to guide practice. Longstanding controversies such as the timing of surgery or the role of antibiotic prophylaxis have not been resolved. The present article reviews the challenges posed by infective endocarditis and outlines current and future strategies to limit its impact.


Infective endocarditis (IE) is a rare disease, but its impact is significant.[1] It affects 3 to 10 per 100,000 per year in the population at large, and epidemiological studies suggest that the incidence is rising.[2–5] In the United States, there are 40,000 to 50,000 new cases each year, with average hospital charges in excess of $120,000 per patient.[3] Despite trends toward earlier diagnosis and surgical intervention, the 1-year mortality from IE has not improved in over 2 decades.

IE is an old problem in a new guise.[6] In the pre-antibiotic and early antibiotic eras, it typically affected young or middle-aged adults with underlying rheumatic heart disease or congenital heart disease (CHD).[7] The development of antibiotics, the decline of rheumatic heart disease, and advances in medicine through the 20th century heralded a change in the risk factor profile, patient demographic characteristics, and the microbiology of IE. Prosthetic valve replacement, hemodialysis, venous catheters, immunosuppression, and intravenous (IV) drug use became the principal risk factors.[8] The average patient was older and frailer, with increasing comorbidities. Concurrently, staphylococci overtook oral streptococci as the most frequent causative organism.[9,10]

In the 21st century, IE has continued to evolve such that it is now health care–acquired in >25% of cases,[9] while advances in cardiology have driven further changes in the patient demographics and manifestations of the disease. Alongside the emergence of cardiac implantable electronic devices (CIEDs), IE affecting complex devices has burgeoned.[11] Similarly, transcatheter valve replacement is revolutionizing the management of valvular heart disease but may be associated with higher rates of IE than surgically implanted prosthetic valves.[12–14]

The present review outlines the challenges posed by contemporary IE in developed countries, as well as the reasons why diagnostic and treatment advances have failed to have an impact on the disease. We highlight recent data on the effect of changing antibiotic prophylaxis guidelines, as well as the current status of molecular and imaging diagnostic strategies, and review policies for improving service delivery and surgical outcomes. Reflecting the constant evolution of the disease, data on IE in 3 patient groups were also examined that encapsulate some of the key challenges: those with transcatheter aortic valve replacement (TAVR)-endocarditis, those presenting with stroke, and those with CIED infection. Finally, we look ahead and emphasize the future need for enhanced clinical care pathways, interdisciplinary collaboration, and research, which will be required for effective disease prevention, diagnosis, and cure.