Pulmonary valve replacement following repair of tetralogy of Fallot: comparison of outcomes between bio- and mechanical prostheses.

Objectives: The aims of this study were to evaluate and compare the outcomes after pulmonary valve replacement (PVR) with a mechanical prosthesis (MP) and a bioprosthesis (BP).

Methods: From 2004 through 2017, a total of 131 patients, who had already been repaired for tetralogy or Fallot or its variants, underwent their first PVR with an MP or a BP. Outcomes of interests were prosthesis failure (stenosis >3.5 m/s, regurgitation >mild or infective endocarditis) and reintervention.

Results: The median age at PVR was 19 years. BP and MP were used in 88 (67.2%) and 43 (32.8%) patients, respectively. The median follow-up duration was 7.4 years, and the 10-year survival rate was 96.4%. Risk factors for prosthesis failure were smaller body surface area [hazard ratio (HR) 0.23 per 1 m2, P = 0.047] and smaller prosthesis size (HR 0.73 per 1 mm, P = 0.039). Risk factors for prosthesis reintervention were smaller body surface area (HR 0.11 per 1 m2, P = 0.011) and prosthesis size (HR 0.67 per 1 mm, P = 0.044). Probability of prosthesis failure and reintervention at 10 years were 24.6% (19.5% in BP vs 34.8% in MP, P = 0.34) and 7.8% (5.6% in BP vs 11.9% in MP, P = 0.079), respectively. Anticoagulation-related major thromboembolic events were observed in 4 patients receiving an MP.

Conclusions: MP might not be superior to BP in terms of prosthesis failure or reintervention. MP should be carefully considered for highly selected patients in the era of transcatheter PVR.