Hemodynamic Efficacy of Annular versus Sub-annular Repair to Repair Functional Tricuspid Regurgitation.

Abstract

Objective: Surgical repair of functional tricuspid regurgitation caused due to annular dilatation and leaflet tethering from a dilated right ventricle is increasingly performed, but the optimal approach for such a repair is unclear. In this study, using a diseased model of FTR, an annular and sub-annular repair strategy were compared in repairing FTR and restoring valve kinematics and mobility.

Methods: A diseased FTR model was developed using porcine hearts placed in a pulse duplicator (n=11 hearts). The effect of annuloplasty ring (TVA) in reducing FTR was first studied, then a sub-annular repair by septal relocation of the posterior and anterior papillary muscles (TVPA) was studied, followed by a combination of the two techniques (TVA+TVPA). FTR was quantified before and after each repair, and real time ultrasound was used to quantify leaflet coaptation, tenting, and leaflet mobility.

Results: At baseline, all valves were competent without FTR. In the FTR model, regurgitation fraction increased to 28±16.2%. With TVA, FTR reduced to 11.3±5.9% (30mm ring), & 4.6±3.8% (28mm ring). With TVPA alone, FTR reduced to 6.5±8.5%. When TVA+TVPA was used, FTR reduced to 2.9±4.3% (30mm TVA+TVPA), and 1.3±1.6% (28mm TVA+TVPA). Largest systolic coaptation height and restoration of leaflet mobility to physiological levels was achieved with TVA+TVPA, with physiological levels of leaflet mobility restored.

Conclusion: In this diseased model, complete correction of FTR, largest systolic coaptation height and restoration of physiological leaflet mobility was achieved with the combination of annular and sub-annular repairs, compared to isolated annular or sub-annular repair.