2 year follow-up of the MITRA-FR study: effectiveness of percutaneous mitral valve repair in secondary mitral regurgitation

Reported from the European Society of Cardiology ESC Congress 2019 in Paris

One year after the presentation of the one-year follow-up results of MITRA-FR, Professor Jean-François Obadia presented the two-year follow-up results of the Mitra-FR study. Again, percutaneous repair added to medical treatment did not significantly reduce the risk of death or hospitalization for heart failure at two years compared with medical treatment alone.

The negative results of MITRA-FR at one-year led to a lot of discussion and hypotheses, especially since the COAPT trial, published a few weeks later, described a lower rate of hospitalization for heart failure and lower all-cause mortality after percutaneous mitral repair, compared to isolated optimal medical therapy. One of the hypotheses was that the shorter follow-up in MitraFr might have precluded the identification of a significant difference and that adding one more follow-up year might lead to different results.

However, the 2-year results only confirmed the initial results of MITRA-FR: 24-month rates of the composite primary outcome all-cause mortality or unplanned heart failure hospitalization were similar in both groups: 64.2% for the MitraClip patients and 68.6% for those managed medically (hazard ratio, 1.01; 95% confidence interval [CI], 0.77 to 1.34). All-cause mortality occurred in 34.9% of patients in the intervention group and 34.2% in the control group (hazard ratio, 1.02; 95% CI, 0.70 to 1.50), and unplanned hospitalization for heart failure occurred in 55.9% of patients in the intervention group and 61.8% in the control group (hazard ratio, 0.97; 95% CI 0.72 to 1.30). There was just a non-significant trend toward more hospitalizations occurring in the medically managed patients.

These results, besides confirming the initial results of MITRA-FR, confirm that the difference between MitraFr and COAPT is rather due to difference in patient characteristics than to a length of follow-up, and should promote further research in the domain of percutaneous repair of secondary mitral regurgitation to better identify the ideal patients for these procedures.

Watch this short interview of Nicole Karam sharing her thoughts about the MITRA-FR trial 2-year follow-up: