Infective Endocarditis After TAVR Linked to Diabetes, Residual Aortic Regurgitation in Large Registry

New insights from a large international registry highlight the high rates of early and late mortality among patients who develop infective endocarditis (IE) after TAVR and may help physicians to identify patients at higher risk of developing this rare but dangerous complication.

Until now, available data on outcomes of IE following TAVR have been limited to small population studies.

“This is so far the biggest study in the field of IE after TAVR,” Norman Mangner, MD (University of Leipzig, Germany), who was not involved in the study, told TCTMD in an email. “It is important to notice that it has a multicenter design overcoming regional differences in the prevalence of IE. Inclusion was very stringent including only those patients with a definite IE according to the modified Duke criteria.”

In their study published today in the Journal of the American Medical Association, Ander Regueiro, MD (Laval University, Quebec City, Canada), and colleagues report that the incidence of IE was 1.1% per person-year in the population of 20,006 TAVR patients from 47 centers in Europe, North America, and South America between June 2005 and October 2015. Median time from TAVR to IE was 5.3 months, and just over half of patients were deemed to have healthcare-associated infections.

After adjustment for confounders, patients who were younger (HR 0.97 per year; 95% CI 0.94-0.99), male (HR 1.69; 95% CI 1.13-2.52), diabetic (HR 1.52; 95% CI 1.02-2.29), and had moderate to severe residual aortic regurgitation (HR 2.05; 95% CI 1.28-3.28) were at higher risk for IE. Additionally, the researchers identified Enterococci species (24.6%) and Staphylococcus aureus (23.3%) as the most frequent microorganisms associated with IE.

Among the 250 IE patients, 14.8% underwent surgery and 36% died during hospitalization. By 2 years, two-thirds of IE patients had died.

The most important thing that this “landmark paper” shows, according to senior author Josep Rodés-Cabau, MD (Laval University, Quebec City, Canada), is that IE “is a very, very serious complication.” Its incidence is after TAVR is “relatively infrequent” but seems on par with what has been observed after surgery, he told TCTMD.

‘Prevention, Prevention, Prevention’

"Careful case-by-case management by the Heart Team remains the cornerstone."

TAVR operators need to become more aware of the potential for IE, especially in high-risk patients, Rodés-Cabau observed. “My first advice would be prevention, prevention, prevention,” he said, suggesting improvements in antibiotic prophylaxis and that clinicians minimize patients’ exposure to healthcare facilities unless absolutely necessary. With regard to the latter, Rodés-Cabau noted that “in some cases you have no choice, but you have to be aware that the more you manipulate these patients the more you can increase their likelihood of having an infection.”

Once a patient is suspected of having IE, only “prompt diagnosis and appropriate therapy” can help them, he said. “In doubtful cases, it’s probably better to start antibiotic therapy rather than wait.”

As to what constitutes high-risk, Rodés-Cabau commented that risk factors like diabetes and residual aortic regurgitation “make sense” but said the link to younger age shown in the study is likely confounded and due to the fact that younger patients usually have a higher comorbidity burden.

Additionally, Mangner said, since the predictors of IE were both patient- and procedure-related, this indicates “that we have to work as perfectly as possible when implanting a valve to prevent those fatal complications.”

Ultimately “clinicians should be familiar with [IE] and investigate more thoroughly, when appropriate, febrile states in patients after TAVR,” Alon Eisen, MD (Rabin Medical Center, Petah Tikva, Israel), told TCTMD in an email.

In the future, studies should look to improve “preventive measures (such as better asepsis and antibiotic prophylaxis), diagnostic strategies, risk factors, and management of IE after TAVR,” Eisen said. “Importantly, the poor prognosis of these patients with conservative management on one hand and the high-risk features of this population on the other hand highlight that careful case-by-case management by the Heart Team remains the cornerstone.”

Note: Three of the study authors are faculty members of the Cardiovascular Research Foundation, the publisher of TCTMD.