Impact of prosthesis-patient mismatch on late recurrence of atrial fibrillation after cryomaze procedure with mitral valve replacement.

BACKGROUND: This study investigated the impact of prosthesis-patient mismatch (PPM) after mitral valve replacement (MVR) with cryoablation using a maze procedure.

METHODS AND RESULTS: We evaluated 142 patients who underwent MVR with a cryomaze procedure. Echocardiography was performed at 1 week and at 1, 3, 5, 7, and 10 years. An effective orifice area index of 1.2 cm(2)/m(2)was used to define PPM. Mean transmitral pressure gradient (mean MPG) >5 mmHg was defined as high. PPM was a risk for overall mortality and a predictor of admission for heart failure. Mean MPG at 1 week was significantly higher in PPM patients (4.8 ± 1.5 mmHg vs. 3.7 ± 1.2 mmHg, P<0.001). Left atrium (LA) dimension decreased after the operation and did not change in patients without high mean MPG, while it increased after 7 years in patients with high mean MPG. The significant predictor of AF recurrence after 1 year was LA dimension ≥ 52.9 mm. Yearly AF recurrence was 10.6% in patients with LA dimension ≥ 52.9 mm, and 1.8% in the others. In patients with high mean MPG, tricuspid regurgitation pressure gradient (TRPG), related to pulmonary artery pressure, was increased after 7 years.

CONCLUSIONS: PPM is a risk for late mortality, admission for heart failure, and high mean MPG, while the last was related to risk of enlargement of LA and increase of TRPG after 7 years. LA dimension after surgery is a predictor of late recurrence of AF, especially when ≥ 52.9 mm.