CTSNet Step-by-Step Series: Tricuspid Annuloplasty
In the case shown in this video, a midline sternotomy was used, which is ideal for multiple procedures. However, a right thoracotomy can be done as a minimally invasive approach if tricuspid repair is being done in isolation. This procedure requires cannulation of both the superior (SVC) and inferior vena cavae (IVC) as well as the aorta. In this video, bicaval cannulation can be seen. This involves placing purse-string sutures in to the right atrium, followed by inserting the cannulae into the SVC and IVC through incisions made with a blade. After the cannulae are secured, snare sutures are put in place. While the procedure can be performed on a beating heart, it is typically done on a nonbeating heart which requires aortic cross-clamping and the administration of cardioplegia.
To access the tricuspid valve, a transverse incision is made from the midatrium toward the IVC. For good visualization, a retractor with valve attachments is required. In the procedure shown, a Cosgrove retractor is used. Before proceeding, the surgeon should inspect the valve to confirm the etiology of tricuspid regurgitation. Interrupted horizontal mattress sutures are then placed around the annulus. These typically begin at the anteroseptal commissure and end near the origin of the coronary sinus. Horizontal Teflon-reinforced sutures enter the atrial tissue just outside the annulus and exit just within the annulus. Extra care must be taken to avoid the triangle of Koch, which is bordered by the septal leaflet and coronary sinus and contains the atrioventricular node. The next step is inserting the ring itself. To do this, the sutures are placed through the ring in an equal distribution in order to seat the ring in a directly annular position. The ring is then lowered down to its annular position, and the sutures are tied. The excess suture material can be cut and discarded. The valve should be tested for competence by pressurizing the right ventricle. The atrium can then be closed with a running stitch. De-airing should be performed prior to removal of the cross-clamp. This is followed by the insertion of pacing wires, routine weaning from bypass, and chest closure.
The annulus can be measured with a sizer using the anterior leaflet for reference, or fixed sizes can be used. Also, note that the tricuspid tissue is more fragile than mitral tissue. The surgeon should stay close to the annulus to avoid damaging important structures including the triangle of Koch, which can cause heart block. Other structures at risk include the aortic valve, right coronary artery, and coronary sinus.