Papillary Muscle Cross-Control Technique to Overcome Excessive Leaflet Tethering in Complex Tricuspid Valve Repair.

Long standing tricuspid valve regurgitation(TR), either with functional or organic origin, might lead to severe right ventricular dilatation and/or dysfunction. The chordal shortening caused by papillary muscle displacement secondary to marked RV dilation results in severe leaflet tethering and progressive lack of coaptation which makes the tricuspid valve repair surgery much more complicated. The annular and RV wall dilatation occurs mostly in the antero-posterior commissure parts and the septal area is less involved. The tricuspid valve tethering distance which is measured as the distance between the annular plane and the coaptation point has been proved as the primary independent parameter predicting the residual TR(1).

Although annular remodeling and downsizing by annulopasty ring restore coaptation in most cases, residual central regurgitation due to excessive leaflet tethering in advanced cases needs to be managed in order to have a better and more durable result. In fact, in the presence of severely tethered leaflets, the TR recurrence rate is 15 to 30% and it has long been recognized that ring annuloplasty is unlikely to successfully treat severe leaflet tethering in TR (2). Some suggested techniques including bicuspidisation , the clover edge to edge technique and patch augmentation, may be mostly either non-physiologic with remaining the tethering, or complex and time consuming(3).

We described a novel technique which overcomes the excessive leaflet tethering, restores coapation and controls right ventricular free wall distension simultaneously. In this simple and reproducible technique, the mostly displaced papillary muscle which is usually in antero-posterior area is controlled by a re-enforced suture which then crosses the ventricular cavity to pass behind the septal leaflet through the septal part of the annuloplasty ring. Controlled pulling of this suture during the water test, pulls down the anterior papillary muscle posteriorly and approximates the leaflets together. The suture is then tied in the most suitable length over the annuloplasty ring. A concomitant advantage of this technique is prevention of overdistension of the right ventricle by approximating the mid anterior free wall to the posterior annulus by a fixed length and subsequent decrease of the wall tension referred to the Laplace's law. This technique can be used in any patient who shows excessive leaflet tethering and apical displacement of the coaptation point after correction of the organic lesion and semi-rigid ring annuloplasty procedure, including patients with simpler condition of long standing functional TR with RV dilatation, as well as patients with much more complex organic tricuspid valve disease such as severe Ebstein anomaly. In most of our cases only one cross-control suture to the dominantly tethering papillary muscle was sufficient but in some cases more than one papillary muscle needed to be controlled.

Our immediate, short, and mid-term results up to 5-year follow-up have been encouraging, showing no increase in RV size or recurrence of TR.

In conclusion, we have found the papillary muscle cross-control a simple, safe and very effective technique to eliminate the compromising effect of leaflet tethering in complex tricuspid valve repair and its use is suggested.

References

1-Fukuda S, Song JM, Gillinov AM, McCarthy PM, Daimon M, Kongsaerepong V, Thomas JD, Shiota T. Tricuspid valve tethering predicts residual tricuspid regurgitation after tricuspid annuloplasty. Circulation. 2005 Mar 1;111(8):975-9.

2-Dreyfus GD, Raja SG, John Chan KM. Tricuspid leaflet augmentation to address severe tethering in functional tricuspid regurgitation. European journal of cardio-thoracic surgery. 2008 Oct 1;34(4):908-10.

3-Choi JB, Kim NY, Kim KH, Kim MH, Jo JK. Tricuspid leaflet augmentation to eliminate residual regurgitation in severe functional tricuspid regurgitation. The Annals of thoracic surgery. 2011 Dec 1;92(6):e131-3.