Infective endocarditis of a transcatheter pulmonary valve in comparison with surgical implants

Melody valved stents (Medtronic Inc, Minneapolis, Minnesota, USA) have become a very competitive therapeutic option for pulmonary valve replacement in patients with congenital heart disease. After adequate prestenting of the right ventricular outflow tract (RVOT) Melody valved stents have a good medium term functional result but are exposed to infective endocarditis (IE).

Retrospective study of tertiary centre Congenital Heart Disease database; to compare incidence of IE in three different types of valved conduits in RVOT: Melody valved stent, cryopreserved homograft (European Homograft Bank) and Contegra graft (Medtronic Inc).

Between 1989 and 2013, 738 conduits were implanted in 677 patients. 107 Melody valved stents were implanted in 107 patients; IE occurred in 8 (7.5%) patients during a follow-up of 2.0 years (IQR 2.4 years, range 0.3-7.8 years). 577 Homografts were implanted in 517 patients; IE occurred in 14 patients (2.4%) during a median follow-up of 6.5 years (IQR 9.2 years; range 0.1-23.7 years). Finally, 54 Contegra grafts were implanted in 53 patients; 11 patients (20.4%) had IE during a follow-up of 8.8 years (IQR 7.7 years; range 0.2-3.5 years). Survival free of IE by Kaplan-Meier for homografts was 98.7% at 5 years and 97.3% at 10 years; for Contegra 87.8% at 5 years and 77.3% at 10 years and for Melody 84.9% at 5 years (log-rank test; p<0.001).

The Contegra conduit and Melody valved stents have a significantly higher incidence of IE than homografts. IE is a significant threat for long-term conduit function.