Attention can now be shifted to the surface of the main pulmonary artery, where an inverted Y incision is planned (dotted lines, Fig. 8.6) into the pulmonary valve sinuses of Valsalva. In the majority of cases, there is a supravalvar narrowing that when properly enlarged can help with the right ventricular muscle resection and can form the basis for a valve-preserving operation. The incision is commenced well into the main pulmonary artery and carefully advanced toward the valve leaflets, where an assessment can be made concerning the orientation and number of valve leaflets. If a three-leaflet pulmonary valve is encountered, the two anterior sinuses of Valsalva are incised to the annulus; if there is a bicuspid valve oriented anterior-posterior, then the incisions are made in the existing sinuses of Valsalva; if the bicuspid valve is oriented in the horizontal position, the incision is made into the anterior sinus of Valsalva. Figure 8.7 shows the inverted Y incision being made into the two existing sinuses of Valsalva in a bicuspid valve oriented in an anterior-posterior position. Careful commissurotomy incisions can enlarge the valve orifice without sacrificing the integrity of the pulmonary valve apparatus. The leaflets should not be detached, only incised. The purpose is to maintain competency of the pulmonary valve. Through the valve, the muscle resection can be assessed, and more resection through this exposure can be accomplished. Measurements can be taken by sized dilators that should be introduced carefully to avoid valvar injury by excessive dilation.
Fig. 8.6
Fig. 8.7
Attention can now be directed to closure of the transatrial VSD. Figure 8.8 demonstrates the exposure for a VSD closure. Interrupted pledgeted sutures are placed commencing at the crest of the right interventricular septum with special care to avoid injury to the tricuspid valve apparatus, the aortic valve, and the conduction system. The suture placement technique is continued as noted in Fig. 8.9. Some sutures may need to be anchored in the right atrium at the tricuspid-aortic annular area. Careful suture placement avoids injury to the septal leaflet and conduction system. The sutures are then placed through a polytetrafluoroethylene (PTFE) patch(Fig. 8.10) and tied in place (Fig. 8.11), all the time assessing the tension of the tie with regard to the dimpling of the pledgeted suture, which is always kept in view. Sutures too loosely tied result in a residual VSD; sutures too tightly applied cause endocardial disruption and a residual VSD.
Fig. 8.8
Fig. 8.9
Fig. 8.10
Fig. 8.11
The patent foramen ovale (PFO) can either be closed or left open, depending on a number of considerations, including small right ventricular size and anticipated right ventricular dysfunction. The right atrium can be closed, and the aortic cross-clamp can be removed after appropriate de-airing maneuvers are performed. Attention can now be directed to the RVOT reconstruction. Figure 8.12 shows an autologous pericardial patch that has been cut to size in a pantaloon configuration to eventually fill out the incised sinuses of Valsalva. Three interrupted sutures are placed and tied at the incised apex of the pantaloon patch to align with the anterior pulmonary valve commissure. The intent of these interrupted sutures is to avoid suture disruption in the event that the resultant right ventricular pressure proves to be too high, which would require a transannular incision in the area of the interrupted sutures. The transannular incision will not disturb the integrity of the rest of the pericardial patch repair. Figure 8.13 shows the pantaloon pericardial patch being sewn into place, augmenting the supravalvar area. If performed correctly, the pericardial patch will be too large and redundant in the superior area of the reconstruction. Tapering the superior portion of the pericardial patch to the estimated exact size risks supravalvar stenosis. Figure 8.14 demonstrates the gathering technique that helps to align the pericardium with the extant pulmonary artery wall. Figure 8.15 shows the completed supravalvar repair.
Fig. 8.12
Fig. 8.13
Fig. 8.14
Fig. 8.15
If right ventricular hypertension occurs after separation from cardiopulmonary bypass, a transannular patch must be performed. Cardiopulmonary bypass is resumed, and one or two interrupted sutures can be removed without disrupting the supravalvar reconstruction. The transannular incisionis made with the intent of preserving the commissural attachments of the pulmonary valve anteriorly. The goal is to preserve the competency of the two leaflets, which are now separated. Recent reports have emphasized this maneuver in the anticipation that these leaflets will grow over time and be available for possible valve restoration in the future by reapproximation, thereby avoiding the placement of homografts, heterografts, or PTFE pulmonary valves at subsequent operations. Once the valve is preserved and the appropriately sized transannular incision into the ventricle is accomplished (Fig. 8.16), another pericardial patch can be placed to augment the original patch (Fig. 8.17).
Fig. 8.16
Fig. 8.17
If the pulmonary valve is deemed to be too small for any attempted valve-sparing strategy, a primary transannular incision can be performed, as in Fig. 8.18. The tenets of valve preservation as noted in Fig. 8.16 are still operative, and special care should be taken to preserve the valve leaflets and commissures in the event that subsequent operations for pulmonary valve regurgitation may find these leaflets applicable for valve restoration. Figure 8.19 shows the limited transannular incisionwith placement of a pericardial transannular patch. Figure 8.20 demonstrates the completed transannular repair.
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