Current Medical Issues

EVIDENCE BASED MEDICINE - SUMMARY OF STUDY
Year
: 2018  |  Volume : 16  |  Issue : 3  |  Page : 101--102

Is transcatheter mitral-valve repair a safe and effective treatment option for secondary mitral regurgitation?


Ann Helen Prasad 
 Christian Medical College, Vellore, Tamil Nadu, India

Correspondence Address:
Dr. Ann Helen Prasad
Christian Medical College, Vellore, Tamil Nadu
India




How to cite this article:
Prasad AH. Is transcatheter mitral-valve repair a safe and effective treatment option for secondary mitral regurgitation?.Curr Med Issues 2018;16:101-102


How to cite this URL:
Prasad AH. Is transcatheter mitral-valve repair a safe and effective treatment option for secondary mitral regurgitation?. Curr Med Issues [serial online] 2018 [cited 2019 Sep 21 ];16:101-102
Available from: http://www.cmijournal.org/text.asp?2018/16/3/101/245042


Full Text

Source: This is a summary of the study: Transcatheter Mitral-Valve Repair in Patients with Heart Failure. The New England Journal of Medicine. 2018.[1] Summary Prepared by Dr. Ann Helen Prasad, Christian Medical College, Vellore, Tamil Nadu, India.

Clinical Question: Is transcatheter mitral-valve repair safe and effective in patients with heart failure with moderate or severe secondary mitral regurgitation who are symptomatic even when using maximal doses of guideline-directed medical therapy?

Authors' conclusions: (1) Transcatheter mitral-valve repair is safe in symptomatic patients with heart failure and secondary mitral regurgitation who are on maximal doses of guideline-directed medical therapy and (2) when compared with medical therapy alone, it results in significantly lower rates of hospitalization for heart failure and mortality, better quality of life, and functional capacity.

 Why this Study?



Heart failure and left ventricular dilatation lead to secondary, or functional, mitral regurgitation.[2] This further increases the volume overload on the heart which worsens the heart failure, reduces the quality of life, and increases mortality.[2],[3] Guideline-directed medical therapy and cardiac resynchronization offer some relief to patients with heart failure and secondary mitral regurgitation; however, the role of a surgical correction remains uncertain.[4] Previous studies have found that surgical repair or replacement of the mitral valve among these patients is associated with considerable risk of complications.[4],[5],[6] Currently, most patients with heart failure and secondary mitral regurgitation are treated conservatively due to the lack of alternatives.[7] The Endovascular Valve Edge-to-Edge Repair Study (EVEREST II trial) showed that transcatheter mitral-leaflet approximation with the MitraClip device (Abbott) is safer than surgical repair.[8] This study attempts to study the role of transcatheter mitral-valve repair as an additional therapy by studying its safety in symptomatic patients with heart failure and moderate-to-severe mitral regurgitation on maximal doses of medication and by assessing its effectiveness when compared with medical therapy alone.

[INLINE:1]

 Results



Transcutaneous mitral-valve repair was found to be safe. The rate of freedom from complications related to the device at 12 months was 96.6% (lower 95% confidence limit, 94.8%), which was significantly above the performance goal of 88% (P < 0.001).

When compared with the control group, the device group had lower rates of annualized hospitalization for heart failure and death. The annualized hospitalization rate for heart failure within 24 months was 35.8% and 67.9% per patient-year in the device and control groups, respectively (hazard ratio, 0.53; 95% confidence intervals [CI], 0.40–0.70; and P < 0.001). In the device group, 29.1% of patients died within 24 months, whereas in the control group, 46.1% died (hazard ratio, 0.62; 95% CI, 0.46–0.82; and P < 0.001). There were also significant improvements from the baseline in the grade of mitral regurgitation, the New York Heart Association functional class, Kansas City Cardiomyopathy Questionnaire score, distance on the 6-minute walk test (P < 0.001 for each), and in the left ventricular end-diastolic volume (P = 0.004).

 Discussion



Apart from medical therapy and cardiac resynchronization, the treatment options available for heart failure with secondary mitral regurgitation are few.[4],[5],[6],[7] This is a cause for concern since medical therapy offers only symptomatic relief and reduces the severity of mitral regurgitation in only a few patients.[4] While surgical options have good rates of success in patients with primary mitral regurgitation, such successes cannot be claimed with surgical mitral-valve repair or replacement, which were in fact found to be unsafe.[4],[5],[6] The recent EVEREST II study demonstrated that the MitraClip device inserted by the transcatheter route was safer than the conventional surgical approach.[8] Thus, in order to test the safety and efficacy of this new option against medical therapy alone, this study was conducted.

The study shows that transcatheter mitral-valve repair is safe, with its rate of freedom from device-related complication exceeding the performance goal significantly. The study also showed that transcatheter mitral-valve repair has lower rates of hospitalization for heart failure and death, lessens the severity of the mitral regurgitation, and improves the quality of life.

 Strengths and Limitations



This study shows that among patients with heart failure with secondary mitral regurgitation (moderate-to-severe and severe grades) who were symptomatic even on maximal doses of medical therapy, the transcatheter mitral-valve repair is both safe and effective. Protocol-specific procedures and guideline-directed medical therapy were used in this study. An independent event committee and a central echocardiographic core laboratory were used.

The limitations of the study were as follows:

Blinding was not possible. Potential bias could not completely be eliminatedThe number of patients who withdrew from the study was higher among the control groupMedication affecting the renin–angiotensinogen system was more often used at the baseline among the patients in the device group.

Financial support and sponsorship

This trial was sponsored by Abbot.

Conflicts of interest

There are no conflicts of interest.

References

1Stone GW, Lindenfeld J, Abraham WT, Kar S, Lim DS, Mishell JM, et al. Transcatheter mitral-valve repair in patients with heart failure. N Engl J Med 2018. doi: 10.1056/NEJMoa1806640.
2Sannino A, Smith RL 2nd, Schiattarella GG, Trimarco B, Esposito G, Grayburn PA, et al. Survival and cardiovascular outcomes of patients with secondary mitral regurgitation: A Systematic review and meta-analysis. JAMA Cardiol 2017;2:1130-9.
3Goliasch G, Bartko PE, Pavo N, Neuhold S, Wurm R, Mascherbauer J, et al. Refining the prognostic impact of functional mitral regurgitation in chronic heart failure. Eur Heart J 2018;39:39-46.
4Stone GW, Vahanian AS, Adams DH, Abraham WT, Borer JS, Bax JJ, et al. Clinical trial design principles and endpoint definitions for transcatheter mitral valve repair and replacement: Part 1: Clinical trial design principles: A consensus document from the mitral valve academic research consortium. J Am Coll Cardiol 2015;66:278-307.
5Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP 3rd, Fleisher LA, et al. 2017 AHA/ACC focused update of the 2014 AHA/ACC guideline for the management of patients with valvular heart disease: A report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol 2017;70:252-89.
6Baumgartner H, Falk V, Bax JJ, De Bonis M, Hamm C, Holm PJ, et al. 2017 ESC/EACTS guidelines for the management of valvular heart disease. Eur Heart J 2017;38:2739-91.
7Goel SS, Bajaj N, Aggarwal B, Gupta S, Poddar KL, Ige M, et al. Prevalence and outcomes of unoperated patients with severe symptomatic mitral regurgitation and heart failure: Comprehensive analysis to determine the potential role of MitraClip for this unmet need. J Am Coll Cardiol 2014;63:185-6.
8Feldman T, Foster E, Glower DD, Kar S, Rinaldi MJ, Fail PS, et al. Percutaneous repair or surgery for mitral regurgitation. N Engl J Med 2011;364:1395-406.