Impact of prosthesis–patient mismatch on tricuspid valve regurgitation and pulmonary hypertension following mitral valve replacement

BACKGROUND: Mitral PPM can be equated to residual mitral stenosis, which may halt the expected postoperative improvement of PH and concomitant functional tricuspid regurgitation (fTR). Aim of the present study is to evaluate the impact of mitral prosthesis-patient mismatch (PPM) on late tricuspid valve regurgitation and pulmonary hypertension (PH). METHODS: A total of 210 patients undergoing isolated mitral valve replacement (MVR) were investigated. Mitral valve effective orifice area was determined by the continuity equation and indexed for body surface area (EOAi) and PPM was defined as EOAi = 1.2 cm(2)/m(2). Pulmonary hypertension (PH) was defined as systolic pulmonary artery pressure (sPAP) > 40 mmHg. Clinical and echocardiographic follow-up (median 27 months) was 100% completed. A total of 88/210 (42%) patients developed mitral PPM. RESULTS: There were no significative differences in baseline and operative characteristics between patients with and without PPM. At follow-up, the prevalence of fTR = 2+ (57%vs.22%; p = 0.0001), and PH (62%vs.24%;p < 0.0001) were significantly higher in patients with PPM. On multivariable regression analysis, EOAi (p < 0.0001) and preoperative left ventricular (LV) end-diastolic diameter (p < 0.0001) were found to be independently associated with fTR decrease after MVR. In addition, EOAi (p < 0.0001) and LV ejection fraction (p < 0.0001) were independently associated with PH decrease after MVR. No significant differences in mortality rates were found between patients having or not PPM. CONCLUSIONS: This study shows that mitral PPM is associated with the persistence of fTR and PH following MVR. These findings support the realization of tricuspid valve annuloplasty when PPM is anticipated at the time of operation