Outcomes after implantation of right-sided mechanical valve prostheses in congenital heart disease

BACKGROUND: Bioprosthetic valves are often used for pulmonary valve replacement (PVR) and tricuspid valve replacement (TVR) because of concerns about mechanical valve thrombosis in the right heart. The purpose of this study was to assess prosthetic valve function and outcomes (prosthetic valve dysfunction, reoperations and major bleeding events) after mechanical PVR and TVR and to compare these to bioprostheses implanted in the same positions. METHOD: Case-control study of adults with congenital heart disease that underwent mechanical TVR or PVR (2003-2021) at Mayo Clinic Rochester, Minnesota. For each mechanical prosthesis, we identified two patients that received bioprosthesis in the same position (1:2 matching). RESULTS: We identified 48 consecutive patients that underwent mechanical PVR (n=39, age 32 (26-38) years, men 22 (56%)) and/or mechanical TVR (n=17, age 36 (31-42) years, men 9 (53%)), as control group of 78 patients (age 30 (24-36) years, men 44 (56%)) and 34 patients (age 34 (29-39) years, men 18 (53%)) that underwent bioprosthetic PVR and TVR, respectively. The most common diagnoses in patients that received mechanical prosthesis were: tetralogy of Fallot (n=14, 19%), aortic stenosis status post Ross operation (n=11, 23%), truncus arteriosus (n=5, 11%), atrioventricular canal defect (n=4, 8%), Ebstein anomaly (n=3, 6%), double outlet right ventricle (n=2, 4%), valvular pulmonic stenosis (n=2, 4%). Compared with the bioprosthesis group, the mechanical prosthesis group had lower temporal increase in Doppler systolic mean gradient after PVR (∆ -1±2 vs 3±2 mm Hg, p<0.001) and Doppler diastolic mean gradient after TVR (∆ 0±1 vs 2±1 mm Hg, p=0.005). The mechanical prosthesis group also had lower risk of prosthetic valve dysfunction after PVR (1.0% vs 2.8% /year, p=0.02) and after TVR (2.6% vs 4.3% /year, p=0.008), but higher risk of major bleeding events (2.2% vs 0.1% /year, p<0.001). CONCLUSIONS: Patients that received right-sided mechanical valve prostheses had lower temporal increase in valve gradient, lower risk of prosthetic valve dysfunction, but higher risk of bleeding complications compared with those that underwent right-sided bioprosthetic valve implantation.