Tricuspid Anteroposterior Patch Repair for Functional Tricuspid Regurgitation is Superior to Anterior Leaflet Augmentation in Relieving Leaflet Tethering and Restoring Coaptation

E. Rodriguez¹, Z. Darby², H. Rando³, I. D. Chinedozi⁴, J. Briscoe⁵, Z. Robinson¹, J. S. Gammie⁶, R. Quinn^1
1Johns Hopkins University School of Medicine, Baltimore, Maryland ²Johns Hopkins, Baltimore, Maryland ³The Johns Hopkins Hospital, Baltimore, Maryland ⁴Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland ⁵Georgetown University, Washington, District of Columbia ⁶The University of Maryland, Stevenson, Maryland

Purpose: Anterior leaflet augmentation (ALA) with annuloplasty is used to repair functional tricuspid regurgitation (FTR) with leaflet tethering, but is associated with conduction defects and does not consistently restore coaptation. We developed a novel tricuspid anteroposterior patch repair (TAPPR) that avoids the conduction system and compared it to ALA with annuloplasty.

Methods: We performed two pericardial patch augmentation strategies in a validated ex-vivo porcine model of FTR. ALA repair (n=5) was performed by detaching the anterior leaflet from the annulus and inserting an elliptical pericardial patch, followed by a semi-rigid annuloplasty ring (ALA+Annuloplasty), as described by Dreyfus et al.1 TAPPR (n=5) was performed by detaching both the anterior and posterior leaflets and implanting a 1.5-cm wide, partial frustum-shaped pericardial patch, sized to the AS-AP commissural distance, followed by annuloplasty (TAPPR+Annuloplasty). Coaptation was marked before and after annuloplasty ring insertion. A structured light scanner was used to acquire a three-dimensional point-cloud of the valve at peak systole; this was subsequently used for geometric analysis of the native, regurgitant, and repaired valve before and after annuloplasty insertion. Annular circumference, leaflet tenting heights and angles, and coaptation were measured using 3D-Scan-to-CAD software and compared between the two repair methods using paired and unpaired t-tests.

Results: Ten hearts were included, divided into two treatment arms. Five underwent ALA repair, followed by annuloplasty (ALA+Annuloplasty), and five underwent TAPPR, followed by annuloplasty (TAPPR+Annuloplasty) (Table 1). FTR was successfully repaired in all hearts with ALA+annuloplasty, TAPPR alone, and TAPPR+annuloplasty. ALA alone led to an average effective regurgitant orifice area (EROA) of 16.0+/-1.5 mm2 and residual TR (EROA >/=0.00 mm2) in 60% of repaired valves (3/5). TAPPR without annuloplasty demonstrated significantly lower septolateral tenting angles (30.3+/-7.2 vs 45.2+/-6.9 degrees, p=0.01) and tenting heights (0.9+/-0.2 cm vs 1.6+/-0.4 cm, p=0.009) compared to ALA+Annuloplasty. Coaptation was comparable between ALA+annuloplasty and TAPPR alone (length: 1.1+/-0.1 cm vs 1.1+/-0.6 cm, p=0.18; area: 10.4+/-2.6 cm2 vs (10.3+/-1.9 cm2, p=0.75). Although the addition of annuloplasty to TAPPR led to increased average coaptation length (1.7+/-0.1 cm vs 1.13+/-0.06 cm, p< 0.001) and area (13.5+/-2.2 cm2 vs 10.3+/-1.9 cm2, p< 0.001), septolateral tenting angles (50.5+/-7.4 vs 30.3+/-7.2 degrees p=0.003) and heights (1.3+/-0.1 cm vs 0.9+/-0.2 cm, p=0.32) were also increased, compared to TAPPR alone.

Conclusion: When comparing to the conventionally used ALA+annuloplasty (Dreyfus) repair method of FTR, TAPPR provided more effective relief of leaflet tethering and restored coaptation without the use of an annuloplasty ring. The addition of an annuloplasty ring to TAPPR provided superior coaptation but also increased leaflet tethering. Tricuspid AnteroPosterior Patch Repair alone is a promising repair for FTR with leaflet tethering, and by avoiding annuloplasty ring placement, may reduce the risk of postoperative conduction abnormalities.

Identify the source of the funding for this research project: N/A