Clin Res Cardiol (2021). 10.1007/s00392-021-01933-9

Cardio Pulmonary Exercise Testing and Feature-Tracking Magnetic Resonance Imaging derived parameters can predict improved functional status in patients undergoing transcatheter mitral valve repair
T. tesfay1, D. Buckert1
1Klinik für Innere Medizin II, Universitätsklinikum Ulm, Ulm;
  • Objective

    Procedural and clinical success after TMVR is usually assessed by soft parameters like NYHA-classification or echocardiographic quantification of residual mitral regurgitation. Both parameters lack scientific robustness.
    The aim of our study therefore was to identify reliable clinical parameters by correlating the findings of ventricular remodelling using feature tracking cardiac magnetic resonance imaging (FT CMR) with the results of CPET (cardiopulmonary exercise testing, or spiroergometry) and thereby identifying clinical parameters to predict improvement of functional status in patients undergoing TMVR.


    During a time period of 18 months (11/2016 – 05/2018) we included 33 patients with symptomatic mitral regurgitation that were planned for minimal invasive mitral valve repair at the university of Ulm. The participants were examined using FT CMR and CPET (cardiopulmonary exercise testing) before and after TMVR as well as a clinical assessment. The follow up extended over a time period of three to six months in which all patients have reported clinical improvement during clinical assessment. For our further study purpose we defined noteworthy clinical improvement as a reduction of at least 2 points on the NYHA-classification scale.


    FT-CMR depicted a significant reduction of left ventricular diameter as noted in a decrease in end diastolic volume within the whole study cohort and regardless of improved functional status. FT-CMR also demonstrated that patients experiencing clinical improvement had no  change in in right ventricular function whereas patients lacking improvement ha numerical worsening of right ventricular function. In general CPET revealed a net improvement in cardiopulmonary resilience after TMVR. Nevertheless when there was no clinical improvement there was also no improvement in CPET parameters. Moreover in patients lacking clinical improvement we observed signs of fixed pulmonary hypertension as signified by an increased Arterio-alveolar gradients and dead space ventilation with TMVR having no effect on neither. Furthermore when performing a ROC-curve for VE/VCO2 -slope we were able to identify a cut-off of below 37 ± 4, 2 as a predictive value that correlates with improved functional status (p-value: 0,002)    


    In patients undergoing TMVR left ventricular remodeling is present but neither correlates with or is being predictive of beneficial clinical outcome. However CPET derived parameters do correlate with clinical improvement in patients undergoing TMVR and also proved to be reliable when examining for possible clinical benefit of TMVR.
    Our findings indicate that the assessment of right ventricular function and pulmonary hypertension is critical for predicting improved clinical status after TMVR.