Background Bacteraemia and infective endocarditis (IE) are rare but severe complications of transcatheter aortic valve implantation (TAVI). Limited data exist on the incidence and microbiological profile of early bacteraemia in this population. This study aimed to evaluate the 6-month incidence of bacteraemia, IE and associated mortality following TAVI.

Methods Using Danish nationwide registries, all patients who underwent TAVI from 2012 to 2021 were identified and matched 1:1 by age, sex and index year with patients who underwent elective coronary angiography (CAG). Outcomes were assessed with cumulative incidence functions and adjusted HRs.

Results Among 5990 patients with first-time TAVI (57% male, mean age 80 years, SD 6.9), bacteraemia occurred in 4.2% within 6 months, compared with 2.6% in the CAG group (adjusted HR 1.57, 95% CI 1.26 to 1.96). Common pathogens post-TAVI included Streptococci (20%), Coagulase-negative staphylococci (19%) and Enterococci (18%), differing from the CAG group, where Coagulase-negative staphylococci (22%) and Staphylococcus aureus (16%) predominated. IE developed in 1.1% of patients with TAVI versus 0.1% of patients with CAG (adjusted HR 20.01, 95% CI 5.97 to 67.48).

Conclusion Bacteraemia and IE rates are substantially elevated within 6 months following TAVI compared with elective CAG. The bacterial profile post-TAVI suggests that current prophylactic antibiotic regimens may not provide adequate coverage.