Long-term mortality after transcatheter Edge-to-Edge Mitral Valve repair significantly decreased over the last decade: comparison between initial and current experience from the MitraUlm Registry

Objectives: The aim of this study was to evaluate whether the M-TEER candidate profile, the postprocedural long-term adverse outcomes and the predictors for long-term mortality have changed over the last decade.

Methods: Long-term follow-up data (median time 1202 days) including mortality, MACCE and functional status were available for 677 consecutive patients enrolled in the prospective MiTra Ulm registry from January 2010 until April 2019.  The initial 340 patients treated in our institution before January 2016 were compared with the following 337 patients who underwent the procedure after January 2016. All patients were followed for at least 3 years.

Results: Patients treated after 2016 showed significant less ventricular dilatation (left ventricular end-systolic diameter 43±13 mm vs. 49±16 mm, p<0.007), significant lower systolic pulmonary pressures (50±15 mmHg vs. 57±21 mmHg, p=0.01), lower peak left atrial pressures (22±18 mmHg vs. 28±18 mmHg, p=0.003) and lower prevalence of severe tricuspid regurgitation (27.2% vs. 47.3%, p <0.001) at baseline than patients treated before 2016. Compared to the cohort treated before 2016, patients treated afterwards showed significantly lower all-cause 3-year mortality (29.4% vs. 43.8%, p <0.001) without differences for MR etiology, as well as significantly lower MACCE (38.4% vs. 54.1%, p <0.001). While severe tricuspid regurgitation and NYHA class IV remained independently associated with increased long-term mortality risk over the past decade, severe left ventricular dilatation (hazard ratio, HR 2.12, p=0.047) and severe pulmonary hypertension (HR 2.18, p=0.047) were predictors of long-term mortality only for patients treated before 2016.           

Conclusion: The M-TEER candidates are currently treated earlier over the course of disease and they benefit significantly in terms of better long-term survival compared to patients treated in beginning of M-TEER era. The predictors for long-term mortality have changed over the last decade, as severe cardiac dilatation and pulmonary hypertension do not represent independent predictors of mortality anymore.