DISCUSSION:
Congestive heart failure (CHF) is the commonest heart problem in the world and is currently one of the leading causes of death and hospitalization in the older age group [1].
Left ventricular remodeling involves two mechanisms: restriction of valve movements and disappearance of cooptation. Then, The vicious circle: ventricular remodeling-mitral insufficiency. Functional mitral regurgitation occurs in the absence of structural mitral valve disease.
Given the better understood mechanisms of mitral regurgitation in dilated cardiomyopathies, the purpose of mitral plastic is therefore to restore a cooptation surface between the valve sheets by reducing the native ring by an undersized circumferential prosthetic ring to obtain valvular continence.
Indeed, the plane of computation of the two valve sheets, due to the hypertraction of the ropes, is moved towards the apex of the ventricle and moves away from the plane of the ring, resulting in a “tent” effect, increasing the covering surface necessary of the two mitral sheets to obtain the closure of the mitral orifice, and this to the detriment of the coaptation surface [2].
It is well established that secondary mitral regurgitation worsens both symptoms and prognosis in patients with left ventricular dysfunction of ischemic and non-ischemic etiology.
Cardiac transplantation has been the standard treatment for patients with severe CHF associated with end-stage heart disease. However, this therapeutic modality has limited applicability.
Alternate surgical strategies to manage patients with severe end stage heart disease have been applied over the last decade or more, including resynchronization therapy, electrical therapy, coronary artery revascularization, cardiomyoplasty, left ventricular myoreduction surgery and mitral valve repair.
Bolling et al. were the first to report the early outcome of remodeling mitral annuloplasty with a flexible posterior ring in 16 patients with severe CHF and mitral regurgitation in 1995[3].
Szalay et al. reported a similar experience among 121 patients with mitral regurgitation and cardiomyopathy having a left ventricular ejection fraction less than 30% [4].
Bolling has emphasized also in many presentations the importance of the undersizing of the flexible ring in reestablishing the ellipsoid shape and somewhat normal geometry of the left ventricular base [5].
Early and intermediate results with implantation of an undersized flexible ring in the posterior mitral annulus suggests that correction of functional regurgitation results in partial reversal of left ventricular remodeling and in symptomatic improvement. Intermediate results are superior to medical treatment alone and comparable to cardiac transplantation [6].
CONCLUSION :
The optimal treatment of functional mitral regurgitation in heart failure patients is still controversial.
Apart from guideline-directed optimal medical therapy, cardiac resynchronization therapy, a durable mitral valve repair has the potential to improve cardiac reverse remodeling and prognosis.