Prognostic significance of right ventricle to pulmonary artery coupling acute improvement after mitral transcatheter edge-to-edge repair

Abstract Background Transcatheter Edge-to-Edge Repair (TEER) of mitral valve is a valid treatment option for severe mitral regurgitation. The right ventricle is acutely affected by early hemodynamic changes following the correction of significant mitral regurgitation. Echocardiographic parameters of the right chambers could have a prognostic impact even in a periprocedural setting. In particular, right ventricle to pulmonary artery coupling improvement may be of pivotal importance, as this parameter is a validated marker of right ventricle function. Purpose To evaluate the prognostic impact of early improvement of right ventricle to pulmonary artery coupling assessed by means of the Tricuspid Annular Plane Systolic Excursion/Pulmonary Artery Systolic Pressure (TAPSE/PASP) ratio after TEER. Methods This retrospective single centre study included patients treated with TEER in our hospital from 2015 to 2023. Transthoracic echocardiography was performed before and shortly after device positioning. Acute effects of TEER on echocardiographic parameters were assessed by paired samples t-test. Diagnostic accuracy of the percent variation in the TAPSE/PASP ratio was assessed by means of receiver-operating characteristics analysis. Prognosis was evaluated by Kaplan-Meier analysis. Results The study included 95 patients (age 78 ± 10 years; 63% men; BMI 25 ± 5 kg/m2) with severe or moderate-to-severe mitral regurgitation. Mean baseline Left Ventricle (LV) ejection fraction was 45 ± 16%, LV end-diastolic volume was 157 ± 62 ml and effective regurgitant orifice area was 41 ± 25 mm2. Post-procedural echocardiographic assessment showed early improvement of LV end-diastolic diameter (p < 0.001), LV end-diastolic volume (p = 0.025), LV stroke volume (p < 0.001), LV global longitudinal strain (p < 0.001), right ventricle free wall longitudinal strain (p < 0.001) and PASP (p = 0.002). Percent improvement of TAPSE/PASP ratio showed a sufficient diagnostic accuracy in predicting a composite outcome of hospitalisation for heart failure and all cause mortality at 1 year (area under the curve 0.66, p = 0.047), with an optimal cut-off of 5.5%. An improvement of the TAPSE/PASP ratio over this threshold was associated with a reduction in the composite outcome (hazard ratio 0.38, p = 0.045). Conclusion TEER improves both left and right ventricular dynamics, which can be detected with echocardiography. In particular, an acute improvement of the TAPSE/PASP ratio is associated with an improvement in short-term prognosis. A comprehensive assessment of right ventricular function, including TAPSE/PASP ratio, should be routinely performed before and after TEER.