Antithrombotic Therapy in Infective Endocarditis: A Retrospective Analysis of Mortality and Complications

Purpose: Thromboembolism (TE) arises in 20% to 50% of patients with infective endocarditis (IE), significantly contributing to mortality. While the pathogenesis of IE includes the formation of vegetations with platelet-fibrin clots, antithrombotic therapy (AT) has not consistently shown to prevent TE. Moreover, because of the increased risk of cerebral hemorrhage, guidelines advise against using AT in the management of IE. However, many patients with IE already receive AT at admission due to pre-existing cardiovascular conditions. This retrospective, multicentric study aims to provide insights into the in-hospital mortality and complications of patients with IE under various regimens of pre-existing AT, compared to IE controls without AT. Methods: A total of 363 patients with IE were included at 2 tertiary hospitals in Belgium. The following groups were compared: 129 patients with IE without AT (group 1), 104 patients with IE with an antiplatelet treatment (group 2), 100 patients with IE under anticoagulant therapy (group 3), and 30 patients with IE treated with combined antiplatelet and anticoagulant agents at admission (group 4). Results: This study found no significant differences in in-hospital mortality ( P = .091), TE ( P = .413), or hemorrhagic stroke ( P = .274) between groups. There was a nonsignificant trend toward reduced vegetation size ( P = .112) in the anticoagulant-treated IE groups 3 and 4. There were significantly more viridans streptococci infections in the younger control group 1 ( P = .012). Conclusion: This analysis challenges the conventional caution against AT use in IE, suggesting that pre-existing AT does not significantly influence mortality or complications in patients with IE.