One-year Outcomes and Predictors of Mortality After MitraClip Therapy in Contemporary Clinical Practice: Results From the German Transcatheter Mitral Valve Interventions Registry

Miriam Puls; Edith Lubos; Peter Boekstegers; Ralph Stephan von Bardeleben; Taoufik Ouarrak; Christian Butter; Christine S. Zuern; Raffi Bekeredjian; Horst Sievert; Georg Nickenig; Holger Eggebrecht; Jochen Senges; Wolfgang Schillinger


Eur Heart J. 2016;37(8):703-712. 

In This Article

Abstract and Introduction


Aims The transcatheter mitral valve interventions (TRAMI) registry was established in order to assess safety and efficacy of catheter-based mitral valve interventional techniques in Germany, and prospectively enrolled 828 MitraClip patients (median age 76 years, median log. EuroSCORE I 20.0%) between August 2010 and July 2013. We present the 1-year outcome in this MitraClip cohort—which is the largest published to date.

Methods and results Seven forty-nine patients (90.5%) were available for 1-year follow-up and included in the following analyses. Mortality, major adverse cardiovascular event rates, and New York Heart Association (NYHA) classes were recorded. Predictors of 1-year mortality were identified by multivariate analysis using a Cox regression model with stepwise forward selection. The 1-year mortality was 20.3%. At 1 year, 63.3% of TRAMI patients pertained to NYHA functional classes I or II (compared with 11.0% at baseline), and self-rated health status (on EuroQuol visual analogue scale) also improved significantly by 10 points. Importantly, a significant proportion of patients regained the complete independence in self-care after MitraClip implantation (independence in 74.0 vs. 58.6% at baseline, P = 0.005). Predictors of 1-year mortality were NYHA class IV (hazard ratio, HR 1.62, P = 0.02), anaemia (HR 2.44, P = 0.02), previous aortic valve intervention (HR 2.12, P = 0.002), serum creatinine ≥1.5 mg/dL (HR 1.77, P = 0.002), peripheral artery disease (HR 2.12, P = 0.0003), left ventricular ejection fraction <30% (HR 1.58, P = 0.01), severe tricuspid regurgitation (HR 1.84, P = 0.003), and procedural failure (defined as operator-reported failure, conversion to surgery, failure of clip placement, or residual post-procedural severe mitral regurgitation) (HR 4.36, P < 0.0001).

Conclusions Treatment of significant MR with MitraClip resulted in significant clinical improvements in a high proportion of TRAMI patients after 12 months. In the TRAMI cohort, the failure of procedural success exhibited the highest hazard ratio concerning the prediction of 1-year mortality.


Mitral regurgitation (MR), the most common type of valvular heart disease, affects nearly 10% of people above the age of 75 years.[1] A recent European analysis[2] demonstrated that ~50% of patients with severe symptomatic MR were denied surgical mitral valve interventions (mostly due to advanced age, impaired left ventricular function and a high burden of comorbidities) indicating the need for less invasive treatment alternatives.

The percutaneous edge-to-edge mitral valve repair with MitraClip (Abbott, Menlo Park, CA, USA) is based on the surgical technique first described by Alfieri.[3] Feasibility in a porcine model[4] and the first human case[5] were both published in 2003. In 2009, the EVEREST I trial (Endovascular Valve Edge-to-Edge Repair Study),[6] demonstrated safety and feasibility of MitraClip implantation for treatment of MR. Subsequently, EVEREST II,[7] a multicentre randomized controlled trial, compared percutaneous repair vs. surgery in operable patients with symptomatic severe MR (≥3+). The percutaneous repair was associated with superior safety and similar improvements in clinical outcomes. However, patients treated percutaneously more commonly required additional surgical procedures for treatment of residual MR at 12 months (20 vs. 2.2%, P < 0.001). At 4 years of follow-up of EVEREST II patients,[8] there was no significant difference in mortality (17 vs. 18%, P = 0.9) and incidence of MR ≥3+ (22 vs. 25%, P = 0.745) between the two groups. Surgery for significant residual MR occurred in 25% of percutaneously treated patients vs. 5.5% of surgically treated patients indicating that only few surgeries were required after the first year of follow-up.

Whereas EVEREST II enrolled only operable patients with predominantly primary MR, large registries on MitraClip therapy demonstrated that real-world patients differ significantly from the EVEREST II cohort[9–11] underlining the continuous need for outcome data derived from industry-independent multicentre real-world studies.

In Germany, catheter-based mitral valve repair has rapidly been accepted at many centres and is performed at increasing numbers. To date, the independent German transcatheter mitral valve interventions (TRAMI) registry comprises the largest multicentre cohort of patients treated with MitraClip implantation world-wide. In the following, we present complete 1-year outcome data of the prospective TRAMI section and aim at identifying predictors of 1-year mortality.