FLEXIBLE RINGS IN COMPARISON WITH RIGID RINGS IN THE TREATMENT OF FUNCTIONAL TRICUSPID INSUFFICIENCY: TWO DIFFERENT MODELS OF REVERSE REMODELING OF THE RIGHT HEART

Objective. To compare the models of reverse remodeling of the right heart after the tricuspid valve repair with rigid or flexible rings.Material and Methods. During the period from September, 2016 to February, 2018, 308 patients who had indications for intervention on the mitral valve and concomitant tricuspid insufficiency without significant differences in clinical status were randomized into two groups. Patients of both groups underwent intervention on the mitral valve with concomitant tricuspid valve repair by a rigid ring (Rigid group, n=154) or a flexible ring (Flex group, n=154)Results. The perioperative mortality rates were 2.0% in the Rigid group and 2.5% in the Flex group (p=0.504). There was no difference in the pacemaker implantation rate (5.1% vs. 2.6%, p=0.238). Freedom from tricuspid insufficiency recurrence at 12 months follow-up was comparable (96.7% in the Rigid group vs 96.1% in the Flex group, p=0.521). The global systolic function of the right ventricle (fractional change in area, FAC; ejection fraction, EF) significantly increased in both groups (p<0.001 for both group) without significant intergroup differences (p=0.231 for FAC; p=0.156 for EF). Intergroup comparison of the regional systolic function (systolic excursion tricuspid valve, TAPSE; longitudinal velocity of the tricuspid valve, S’) showed that patients of the Flex group had significantly higher increases in the parameters (p<0.001 for TAPSE; p=0.002 for S’).Conclusion. Both types of the devises had low rates of recurrence of tricuspid insufficiency at the midterm follow-up and contributed to the restoration of the global systolic function of the right ventricle. However, the rigid rings due to their design fix the tricuspid valve annulus, which inevitably affects the regional systolic function. In perspective, the flexible rings can function without interfering with the restoration of the natural shape of the tricuspid valve annulus and its uniform contraction during the cardiac cycle, thus ensuring a significant increase in regional systolic function.