Bad prognosis for post-MitraClip mitral valve stenosis: how do we proceed?

Courtesy of Dr. Carlos Fava

The EVEREST II trial showed the MitraClip had similar mortality rate to that of surgery but, even though residual mitral valve regurgitation (MR) is associated to a strong negative impact, little is known about post MitraClip increased transvalvular gradient and its implication. 

268 patients undergoing MC implantation were analyzed. After the procedure, the pressure gradients over the mitral valve were determined simultaneously invasively and echocardiographically in 200 of these patients. They were separated in two groups according to a cutoff value of 5 mmHg LA-LV gradient, which resulted in150 patients with ≤5 mmHG gradient and 50 with >5 mmHg gradient.

Combined final end point was all cause mortality, left ventricular assist device, mitral valve replacement, and redo procedure.

There were no significant differences between the groups. All patients presented functional class III-IV cardiac failure, increased B-type natriuretic peptide (BNP), in most patients MC was functional, ejection fraction was 39% and the EUROS-corelog 20%. Mean age was 77.

The number of implanted MitraClip was slightly higher in those presenting >5 mmHg. On the other hand, procedure related complications rate was rather low.

There was a lineal correlation between mitral valve area <4 cm2 and increased gradient >5 mmHg after procedure.

Follow up was at two years: all-cause mortality at one and two years was 22% and 30% respectively. Those presenting MC ≥2 experienced higher mortality rate.

The Kaplan-Meier analyzis showed an increase combined end point (p=0.001) higher all-cause mortality (0.018) for those presenting invasively determined mitral valve pressure gradient (MVPG) in excess of >5 mm and for the echocardiographically determined MVPG the cutoff value was >4.4 mm Hg.

Predictors of bad evolution were the presence of >5 mmHg gradient (hazard ratio 2.3; 95% confidence interval: 1.4 to 3.8 p=0.002), age, B type natriuretic peptides, and the presence of mitral regurgitation >1.

Conclusion

We recommend that the quality of devices be analyzed thoroughly and that the MitraClip be repositioned in cases with elevated mitral valve pressure gradient.

Commentary

All prior analyzis had been focused on assessing residual mitral regurgitation. Instead, this study shows post MitraClip mitral valve stenosis is associated with a strong negative impact, even more when associated with mitral regurgitation.

This is why we should be extra careful as to when to release the MitraClip, and obsessively analyze hemodynamic values with ETE. 

Courtesy of Dr. Carlos Fava.

Original Title: Elevated Mitral Valve Pressure Gradient after MitraClip Implantation Deteriorates Long-Term Outcomes With Severe Mitral Regurgitation and Severe Heart Failure.

Reference: Michael Neuss, et al. J Am Coll Cardiol Intv 2017;10:931-9.

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