Across the Curtain: Benchmarking Differences in Aortic vs. Aortic and Mitral Valve Endocarditis

A. Nissen¹, J. Wei¹, J. Binongo¹, W. Farrington¹, B. Leshnower², W. Brent. Keeling^1
1Emory University, Atlanta, Georgia ²Emory University School of Medicine, Atlanta, Georgia

Purpose: Infective endocarditis involving the aortic and mitral valves is common, yet accrual and reporting of large experiences is rare. Significant knowledge gaps remain in benchmarking the incremental risk added when infective endocarditis goes beyond isolated aortic valve to also include the mitral valve. This research sought to bridge these gaps.

Methods: 992 patients underwent surgery for infective endocarditis at our institution from January 2014 through August 2022. Among these, 385 were treated for isolated aortic valve (AV) endocarditis, and 96 for aortic+mitral (A+M) double valve endocarditis. These groups were compared in terms of preoperative characteristics, intraoperative findings, and postoperative outcomes. Further subgroup analyses were performed among patients with active and treated endocarditis.

Results: Groups were well-balanced in terms of most preoperative characteristics, including heart failure symptoms, urgency, and predicted risk of mortality (Table). The A+M endocarditis group required longer aortic cross clamp and bypass times, as well as more frequent intraoperative transfusions (p < 0.05). The isolated AV group was more likely to require a concomitant aortic procedure (34.8% vs. 17.7%, p< 0.001). Although postoperative mortality was not statistically different between the AV vs. A+M groups (11.6% vs. 9.5%, p=0.5), several major morbidities were more frequent in the A+M group. These included reoperation for bleeding (6.0% vs 13.5% p=0.01), renal failure (5.5% vs. 15.6%, p< 0.001), and prolonged ventilation (26.1% vs. 38.5%, p=0.02). Increased risk for bleeding, renal failure, and prolonged ventilation were also preserved in the active and treated endocarditis subgroups. Rates of active vs. treated endocarditis were stable over the study period (Figure 1). Postoperative stroke, and need for permanent pacemaker were not different between groups.

Conclusion: We report the largest series of double valve endocarditis, and one of the first comparisons benchmarking differences in short-term risk between isolated aortic vs. A+M valve endocarditis. Compared to isolated aortic valve endocarditis, A+M endocarditis is associated with increased risk of transfusion, postoperative bleeding, and new-onset renal failure. Increased rates of postoperative stroke, need for new pacemaker, and early mortality were not evident at a high-volume center. These results support centralizing operative management of this complex disease.

Identify the source of the funding for this research project: None.