The Mosaic mitral valve bioprosthesis: A long-term clinical and hemodynamic follow-up

Background: This study evaluates the clinical and hemodynamic long-term performance of the Mosaic porcine bioprosthesis (MB) after isolated mitral valve replacement (MVR). Methods: From 1995 to 2011, 100 patients (64 men, 36 women; mean age: 73±10 years) had MVR with a MB. Preoperatively mean NYHA class was 3.0 ± 0.7 and 52 patients were in atrial fibrillation. Prosthetic sizes were mainly 27mm (50 patients) and 29mm (40 patients). Follow-up ended in December 2012 and is 97% complete, with a cumulative duration of 611 patient/years (mean 6.0±4.6 and maximum 17.7 years). Results: Early mortality was 10%, being 6% in elective patients; late deaths occurred in 31 patients, 5 being valve-related. Actuarial survival at 5, 10 and 15 years is 74±5%, 50±6% and 37±8%. Mean NYHA class in late survivors is 1.4 ± 0.6 (p<0.0001). Thromboembolic episodes occurred in 4 patients with an actuarial freedom at 15 years of 91±5%. No cases of endocarditis were observed. Four patients required reoperation, 2 for structural valve disease (SVD), 1 for perivalvular leak and 1 for valve thrombosis. Actuarial freedom from SVD and from reoperation is 93±5% and 91±5% at 15 years. Echocardiographic follow-up showed in patients with a 27mm MB a mean gradient of 5.0±1.7 mmHg and an effective orifice area (EAO) of 1.57±0.3 cm2; in patients with a 29mm MB the mean gradient was 4.5±1.9 mmHg and the EOA 1.63±0.4 cm2. Conclusions: The MB has shown good overall clinical and hemodynamic performance after MVR up to > 15 years of follow-up.