Abstract Body (Do not enter title and authors here): Background:
Patients undergoing maintenance hemodialysis (HD) are at increased risk of infective endocarditis (IE), but current data regarding their clinical profiles and outcomes remain limited. We aimed to evaluate the clinical characteristics, treatment patterns, and in-hospital outcomes of IE in HD patients using a nationwide database.

Methods:
We analyzed data from the Japanese Registry of All Cardiac and Vascular Diseases–Diagnosis Procedure Combination (JROAD-DPC) between April 2018 and March 2021. Adult IE patients who received antibiotics and underwent echocardiography were included. HD patients were identified using diagnosis codes for end-stage renal disease. Clinical and institutional characteristics, in-hospital mortality, complications, and cardiac surgery rates were compared between HD and non-HD patients. Predictors of in-hospital death in HD patients were assessed using multivariable mixed-effects logistic regression.

Results:
Of 12,158 IE patients, 806 (6.6%) were on maintenance HD. Compared with non-HD patients, HD patients were older (71.1 vs 68.8 years), had lower Barthel Index scores, and higher rates of diabetes (35.5% vs 18.2%) and peripheral vascular disease (6.6% vs 3.9%) (all p<0.05). Cardiac predisposing conditions such as atrial fibrillation and valvular disease were less common in the HD group. In-hospital mortality was significantly higher in HD patients (30.0% vs 13.5%, p<0.05), and they experienced more cerebrovascular complications (33.6% vs 29.0%). Cardiac surgery was performed less frequently in the HD group (23.4% vs 29.2%, p<0.05).
Among HD patients, independent predictors of in-hospital death included older age (OR 1.45), impaired activities of daily living (non-full Barthel Index; OR 0.54), peripheral vascular disease (OR 3.31), and cerebrovascular complications (OR 1.73). Hospitals with higher cardiac surgery volumes were associated with lower mortality and higher surgical intervention rates among HD patients.

Conclusions:
HD patients with IE had worse in-hospital outcomes, including higher mortality and complications, and were less likely to undergo surgery despite potential benefits. However, treatment at high-volume surgical centers was associated with improved outcomes. These findings highlight the need for optimized multidisciplinary care and referral strategies in this high-risk population.