Right ventricular (RV) dysfunction, elevated pulmonary artery pressure (PA), and severe tricuspid regurgitation (TR) are associated with adverse outcome in patients undergoing percutaneous mitral valve repair (PMVR) due to symptomatic mitral regurgitation (MR). PMVR can improve clinical symptom in some but not all treated patients. The prognostic impact of PMVR on RV function and TR severity remains unclear. Pre-existing RV impairment might be associated with lack of clinical improvement short-term and long-term in certain subgroups of patients.
We retrospectively analyzed a consecutive cohort of 100 patients with symptomatic primary or secondary MR and preprocedural RV dysfunction undergoing PMVR. RV dysfunction was defined as RVEDD >30mm and impaired RV function (TAPSE <20 mm). The primary combined endpoint was defined as all-cause death and heart failure-related rehospitalization. During a median follow-up (FU) of 29 months 32 patients reached the endpoint.
All patients undergoing PMVR suffered from symptomatic MR with NYHA class ³3 at baseline. 83 patients reported NYHA class £2 at 12 months FU, while only 59 patients presented with clinical improvement (NYHA £2) at 36 months. We found a significant decrease of MR severity (MR £2) in 96 patients postprocedurally. 83 and 63 patients showed MR £2 at 12 and 36 months FU, respectively. LVEF was improved after 12 and 24 months FU, respectively in 62 and 81 patients. 64 patients showed a significant decrease of LVEDD after 24 months FU, while LVEDD and LVEF worsened in 19 patients at 36 months FU. MV annular diameter significantly decreased during 36 months FU in 79 patients. 37 patients with RVEDD >40mm before PMVR showed significant reduction of RV diameters of > 5mm at 12 months FU, which remained significant after 36 months FU. Moreover, 74 patients with preprocedural TAPSE <17mm showed a significant improvement of TAPSE at 12 and 24 months FU, which was not observed at 36 months FU. Interestingly, patients with secondary MR showed a significantly higher increase of TAPSE during FU compared to patients with primary MR. Significant decrease of TV annular diameter >5 mm was found in 25 patients at 24 and 36 months FU, while 33 patients developed an enlargement of TV annulus >5 mm during 36 months FU. Severity of TR decreased in 16/48 patients with severe TR at baseline to TR £2 at 12, 24 and 36 months FU. A significant reduction of PA > 5 mmHg was documented in 59 patients. Peak reduction effects on PA were shown at 12 months FU. In our cohort, men seemed to benefit more from PMVR regarding significant improvement of clinical symptoms, MR severity, and RV-function. During FU 27 patients reached the combined endpoint. Increased RVEDD, impaired RV function, elevated PA, and severity of TR were associated with clinical outcome but the effects of PMVR on right heart function parameters did not serve as independent predictors in regression analysis for the combined endpoint.
Our findings suggest that pre-existing right heart dysfunction at baseline is associated with clinical outcome after PMVR. PMVR shows beneficial effects on parameters of RV function and reduction of TR in a subgroup of patients. However, effects of PMVR on right heart parameters were not associated with a favorable clinical response or prognosis short-term and long-term in our cohort of patients with primary and secondary MR.