All patients included in the study underwent TAVR at one of 15 hospitals in Switzerland from February 2011 to July 2018. Overall, infective endocarditis occurred in 149 patients—it was “definite” in 63.1% of patients and “possible” in the remaining 36.9%. All infective endocarditis cases were confirmed using a three-step process that included reviews by local and independent infections disease specialists.
These are four key takeaways from the team’s findings:
1. Infective endocarditis is the most common in the first 99 days following TAVR. The incidence rate in those first 99 days was 2.59 per 100 person-years. From 100 days to one full year after TAVR, the incidence rate dropped to 0.72 events per 100 person-years.
2. The pathogen most commonly associated with early infective endocarditis was Enterococcus species. Meanwhile, the authors noted, 47.9% of patients with early infective endocarditis had a pathogen “not susceptible to the peri-procedural antibiotic prophylaxis. Does this mean a shift in treatment strategy should be considered?
“Based on the observed differences in the spectrum of pathogens between surgical and transcatheter heart valve interventions, a change in antibiotic prophylaxis for transcatheter heart valve interventions to an intravenous dose of amoxicillin/clavulanic acid, ampicillin/sulbactam, or vancomycin in patients allergic to penicillin may be reasonable,” wrote lead author Stefan Stortecky, MD, Bern University Hospital in Switzerland, and colleagues. “However, while broadening antibiotic prophylaxis is a simple intervention with minimal acute risk and cost, the growing problem of antibiotic resistance must be taken into consideration, and it remains to be demonstrated whether a change in antibiotic prophylaxis is effective to mitigate the risk of peri-procedural endocarditis.”
3. The authors noted numerous independent predictors of infective endocarditis. Younger age, male sex, no pre-dilatation balloon aortic valvuloplasty before the valve implantation and being treated in a cardiac cath lab were all associated with infective endocarditis following TAVR.
4. Infective endocarditis leads to a “considerable risk” of mortality and stroke.
“Patients with infective endocarditis had a sevenfold increased risk of mortality during the first year after diagnosis of endocarditis compared with a case-matched population, and this effect was consistent for peri-procedural, delayed early, and late endocarditis events,” the authors wrote. “Of interest, patients with infective endocarditis were at fourfold increased risk of stroke, which was mainly related to events after late occurrence of infective endocarditis.”