Trends and Outcomes of Infective Endocarditis in Adults With Tetralogy of Fallot: A Review of the National Inpatient Sample Database

Background: Lesion complexity and prosthetic valves are known risk factors for infective endocarditis in patients with congenital heart disease. Tetralogy of Fallot (TOF)is the most common complex/cyanotic congenital heart disease and often requires prosthetic valve implantation. Population-based risk of endocarditis in TOF patients is unknown. Methods: We reviewed the National Inpatient Sample (NIS)and identified admissions in TOF patients (>18 years), 2000 to 2014. The primary outcome was to describe incidence of endocarditis-related admissions. To assess trends, we divided the study period into tertiles: early (2000 to 2004), mid (2005 to 2009)and late (2010 to 2014)eras. The secondary outcome was to compare in-hospital mortality, complications, and health care resource utilization between admissions with and without endocarditis. Results: There were 393 (2.1%)endocarditis-related admissions among 18,353 admissions, and the incidence of endocarditis-related admissions increased over time: 1.9% (early era)vs 2.2% (mid-era)vs 2.4% (late era), P < 0.001. Overall in-hospital mortality was 6%. In addition to previously described risk factors for endocarditis, such as previous pacemaker/defibrillator or prosthetic valve implantation, we observed an association between endocarditis-related admissions and male gender, black race, and lower socioeconomic class. In comparison with admissions without endocarditis, the endocarditis-related admissions had higher in-hospital mortality, complications, and health care resource utilization measured by length of stay, inflation-adjusted hospitalization cost, and type of hospital discharge. Conclusions: Incidence of endocarditis-related admissions increased over time and was associated with higher mortality, complications, and health care resource utilization. Further studies are required to investigate the observed temporal increase in incidence of endocarditis and explore new strategies to improve outcomes.