Infective Endocarditis After TAVR: Key Points

The following are key points to remember from this state-of-the-art review on infective endocarditis (IE) after transcatheter aortic valve replacement (TAVR):

1. General. Infective endocarditis (IE) following TAVR is a challenging clinical scenario because of its unique clinical and microbiological profile, a high incidence of IE-related complications, the uncertain role of cardiac surgery, and a very poor prognosis in most patients.
2. Epidemiology. Based on observational registries, nondedicated randomized trials, and nationwide administrative databases, estimates of the incidence of IE after TAVR (TAVR-IE) vary from 0.3 to 2.0 per 100 person-years. Although data are conflicting, large observational cohorts and meta-analyses of randomized controlled trials suggest similar incidence rates for TAVR-IE and IE after surgical aortic valve replacement (SAVR), and no differences in the incidence rate of early IE after TAVR compared to SAVR.
3. Risk factors. There are both patient-specific and procedure-specific risk factors associated with TAVR-IE. There are not compelling data to support that TAVR-IE risk is associated with TAVR device type or whether TAVR was performed in a catheterization laboratory or in a hybrid operating room.
4. Microbiology. Whereas staphylococci are the leading cause of native IE and prosthetic valve IE (PVE) in high-income countries, the most common micro-organisms associated with TAVR-IE are enterococci, S. aureus, and coagulase-negative staphylococci. More than half of TAVR-IE cases are health care associated, which is more than twice the rate observed with IE after SAVR; and often is associated with a multidrug-resistant organism.
5. Clinical features. Atypical clinical presentations and nonspecific symptoms are more frequent in TAVR-IE, commonly leading to delayed diagnosis and treatment. Whereas fever is present in approximately 90% of patients with IE in the general population, it is estimated to be present in only 15-80% of patients with TAVR-IE.
6. Diagnosis. The modified Duke criteria have a lower diagnostic accuracy for TAVR-IE than for native valve IE, and combined transthoracic and transesophageal echocardiography have a lower sensitivity for diagnosing TAVR-IE than for native IE or surgical PVE. Almost one third of patients with TAVR-IE had IE involving at least two cardiac structures (including the mitral valve, implanted cardiac devices, or right-sided IE). Computed tomography, magnetic resonance imaging, and metabolic imaging can be useful as part of a multi-imaging approach for the diagnosis of TAVR-IE.
7. Prognosis. TAVR-IE is associated with a high rate (up to ~70%) of serious complications, including acute heart failure, acute renal failure, septic shock, acute myocardial infarction, and systemic embolization; and high rates of in-hospital (16-64%) and 1-year mortality (27-75%) that are consistently higher than those for native-valve IE or surgical PVE.
8. Management. Optimal management includes a multidisciplinary approach with the use of an Endocarditis Team. The role of surgery in addition to antibiotics has not been rigorously studied, but most reports describe very low rates of surgical intervention for TAVR-IE; and three relatively small studies in unselected, high-surgical risk TAVR-IE patients reported no improvement for in-hospital mortality, 30-day readmissions, or all-cause 1-year mortality associated with surgery. The authors propose a management algorithm for TAVR-IE that includes the use of an Endocarditis Team; assessment for a surgical indication; and assessment of surgical risk, concomitant clinical conditions, and anatomical features that would affect surgical intervention.
9. Prevention. Because of the poor prognosis and limited therapeutic options, prevention of TAVR-IE should be emphasized. Along with antiseptic measures, most consensus recommendations advocate periprocedural antibiotic prophylaxis among patients undergoing TAVR; because of the high rate of early TAVR-IE with organisms that are not susceptible to the usual cephalosporin monotherapy, some propose altering the antibiotic regimen for greater coverage against enterococci. In addition to minimizing health care associated procedures that could lead to a blood stream infection, some question whether the use of periprocedural antibiotic prophylaxis (analogous to antibiotic prophylaxis before a dental procedure) should be used among TAVR patients undergoing invasive respiratory, gastrointestinal, urogenital, or skin procedures.
10. Future perspectives. The authors advocate for specific guidelines for the management of TAVR-IE, and for future studies to address the potential benefits of surgery among at least some patients with TAVR-IE.