Revisiting Prosthesis Choice in Mitral Valve Replacement in Children: Durable Alternatives to Traditional Bioprostheses

Abstract

Purpose: To determine risk factors for re-replacement and death or transplant following mitral valve replacement (MVR) in children. Methods: This is a retrospective 26-year review of patients less than 20 years undergoing MVR between 1992 and 2018 at single institution. Outcomes included freedom from re-MVR and transplant-free survival. Cox proportional hazards regression models assessed association between outcomes and potential risk factors. Results: At median age 4.2 years, 190 children underwent 290 MVR: 180 mechanical, 63 porcine, 13 pericardial, 34 stented bovine jugular vein valves. Re-MVR occurred in 100 valves. Freedom from re-MVR at 5 and 10 years was 76% and 44%. Times to re-MVR were associated with prosthesis type (p<.001), with porcine and pericardial valves at highest risk. Other risk factors for prosthetic failure included smaller prosthesis size and LV hypoplasia. There were 9 transplants and 44 deaths. Transplant-free survival at 5 and 10 years was 81% and 76%. Prosthesis type was significantly associated with time to death/transplant in univariate analysis only (p=0.021), with porcine at higher risk than mechanical. Independent risk factors for death/transplant included larger indexed geometric orifice area and longer bypass time. Conclusion: In pediatric patients undergoing MVR, mechanical and stented bovine jugular vein valves were associated with increased durability compared to fixed-diameter bioprosthetic alternatives.