Risk factors for infective endocarditis following transcatheter pulmonary valve replacement in patients with congenital heart disease

OBJECTIVES: We sought to delineate the risk factors for infective endocarditis (IE) in patients undergoing transcatheter pulmonary valve replacement (TCPVR). BACKGROUND: Despite the therapeutic benefits of TCPVR for treatment of dysfunctional right ventricular outflow tracts, IE is a major complication of the approach. Specific hemodynamic gradients and patient immune status as predisposing factors for IE are largely unexplored. METHODS: We performed a retrospective review of patients who had undergone TCPVR at UCLA between October 2010 and October 2017. Cases of IE were diagnosed based on the modified Duke criteria. RESULTS: Two hundred and thirty-five cases of TCPVR were performed with a mean follow-up of 2.6 years (range 0.0-8.0 years). Sixteen distinct IE events developed in 13 patients (Melody™ n = 12, SAPIEN n = 1), with a median time from implant to IE of 3.3 years (range 2.0-7.2 years). Univariate Cox regression showed that immunocompromised status was significantly associated with the development of IE hazard ratios (HR 5.43 [1.80-16.4], p = .003). Kaplan-Meier curves show that the 5-year freedom from IE among immunocompetent patients was 87% (95% CI 78-96%) versus 64% (95% CI 39-89%) among immunocompromised patients (log-rank p = .02). Postimplant right ventricular systolic pressure was higher among immunocompromised patients (p = .03). The risk of IE post-TCPVR in immunocompromised patients with residual pulmonary stenosis was 43%. CONCLUSIONS: Among the risk factors examined in this study, immunocompromised status was the most significant predictor of IE development post-TCPVR. Patients with the lowest risk of IE are those with competent immune systems, without a history of IE, and with minimal residual pulmonary valve gradients post-TCPVR.