P4190Incidence of infective endocarditis in patients considered at moderate risk

Background: Stratification of patients at risk of infective endocarditis (IE) remains a cornerstone in guidance of prophylactic strategies of IE. However, little attention has been given to patients considered at moderate risk. Purpose: To assess the comparable risk of IE among patients considered at moderate IE-risk, a background population, and a population at high-risk (prosthetic heart valve). Methods: Using Danish nationwide registries, we assessed patients with a diagnosis of aortic and mitral valve disorders, cardiac implantable electronic device (CIED), as well as hypertrophic cardiomyopathy (HCM) and compared these patient groups with 1) controls from the background population using risk-set matching and 2) a high-risk population (prosthetic heart valve). Cumulative incidence plots and multivariable adjusted Cox proportional hazard analysis were used to compare risk of IE between risk groups. Results: We identified 94,996 patients with aortic or mitral valve disorder, 50,377 with a CIED, and 4,339 with HCM. The cumulative risk of IE after 10 years was 0.9% in valve disorder, 1.3% in CIED, and 0.5% in HCM-patients. Compared with the background population, valve disorder, CIED, and HCM carried a higher associated risk of IE, HR=12.26 (95% CI: 8.73–17.22), HR=11.21 (95% CI: 6.21–20.24), and HR=7.95 (95% CI: 3.36–18.81), respectively. All three study groups were associated with a lower risk of IE compared with high-risk patients, HR=0.33 (95% CI: 0.27–0.40) for valve disorder, HR=0.32 (95% CI: 0.26–0.40) for CIED, and HR=0.17 (95% CI: 0.09–0.33) for HCM.