*Step 5: Fenestration of the Cone apex.*

The linear attachment of the leaflets can cause obstruction of blood inflow to the RV. To prevent obstruction, fenestrations of the 1/3 distal attachments of the leaflets and division of papillary muscles are usually applied.

*Step 6: Cone attachment to the true tricuspid annulus.*

The cone is attached proximally to the true annulus over 360 degrees and with no tension in the horizontal or vertical plane (**Figures 19** and **20**). The proximal cone circumference must be correctly matched to the true annular dimension. If necessary, the true annulus can be further reduced by separate plication at 2–3 o'clock and 9 o'clock, and the cone proximal circumference can be reduced by leaflet plication. The initial attachment and assessment are performed with the placement of 5-0 polypropylene single sutures to achieve an even distribution of the valve in the tricuspid annulus. The suture line is then completed with a running suture. To reduce the risk of heart block, special care should be taken when suturing the area of the annulus just medial to the coronary sinus. In this area, the valve can be sutured in a proximal position, in the Todaro's tendon. In patients with a fragile adult-size annulus, the use of a prosthetic ring may be considered for reinforcement.

#### **Figure 19.**

*Cone attachment to the true tricuspid annulus. The constructed cone (a) is reattached to the true tricuspid annulus starting at the anterior position (b) and completing the attachment (c), taking superficial bites when suturing near the atrioventricular node area (arrow) (with permission from reference [58]).*

#### **Figure 20.**

*Cone construction was done by rotation of the posterior leaflet, which was combined with the septal leaflet (a), before attachment to the true tricuspid annulus (b). AL = anterior leaflet, PL = posterior leaflet and SL = septal leaflet (with permission from reference [58]).*

### *Step 7: Atrial septal defect treatment.*

The ASD/PFO are closed in a valved fashion, such that blood can be shunted from right to left in the event of postoperative RV failure. The opening size of the resulting orifice should be proportional to the degree of RV dysfunction or enlargement. This can be accomplished with the single-stitch technique in cases of PFO or by using a polytetrafluoroethylene (PTFE) patch with an extension flap positioned inside the left atrium to allow unidirectional blood flow toward the left atrium. In cases of severe RV dysfunction, the single-stitch technique (**Figure 20**) can be performed with placement near the PFO anterior corner, which will result in a less restrictive PFO. In cases of RV dysfunction, some authors recommend the bidirectional Glenn procedure as an adjunct to Ebstein's anomaly repair [53, 59–62]. We have considered using the Glenn procedure in some patients, as we will describe in the neonatal section.

## **7.4 Special anatomic types of Ebstein's anomaly**

In some anatomical situations, the three leaflets are connected at the commissures and there is a well-formed distal attachment of the TV to the RV. In such cases, the TV leaflets are mobilized from their displaced hinge line and the TV is released from its abnormal connections to the RV wall. Next, some plications are made at the distal and proximal edges of the TV, reducing its proximal and distal circumferences, and widening the septal and posterior leaflets to give it a cone shape.

The cone technique can also be used to treat patients presenting with Ebstein's anomaly with Carpentier's type D anatomy. **Figure 21** depicts one of our patients who was successfully repaired by taking down the leaflets as a single piece, retaining only the distal direct attachment of the leaflet to the RV. Vertical fenestrations were provided at the distal third of this large leaflet. Then the lateral and medial edges of this leaflet were sutured together, creating a cone-like structure. As in all other cases, the cone was revised and any holes/fenestrations in the proximal 2/3 of the cone's membranous tissues were closed to achieve a similar circumferential depth and to prevent regurgitation leaks. Furthermore, natural, or surgically created fenestrations should be present at the distal 1/3 of the cone to permit unrestricted forward blood flow in diastole.

#### **7.5 Important notes on Da Silva cone technique**

The mechanism of tricuspid insufficiency in Ebstein's anomaly is usually related to restrictive leaflet movements. This occurs due to failure of leaflet delamination that results in more distal hinge line attachment to the RV, as well as to the presence of muscular bridges and abnormal papillary muscles that tether the TV leaflets to the RV wall, restricting their movements. Creating a competent tricuspid valve using the cone technique requires extensive mobilization of the displaced or tethered leaflets. Otherwise, the repair will result in leaflet coaptation failure or excessive tension in the leaflet suture line due to pulling of the leaflet that remained improperly attached to the free RV wall, which will be subject to strong tension when the RV is filled. An understanding of these concepts is essential to minimize the incidence of tricuspid insufficiency after the cone procedure and to prevent postoperative dehiscence of the suture line due to diastolic tension. The septal leaflet is frequently incorporated into the septal aspect of the cone, in combination with the posterior tricuspid leaflet. This is a very important component of the cone technique, as it helps prevent both stenosis and insufficiency of the tricuspid valve.

**(a) (b)**

**Figure 21.** *Preoperative magnetic resonance images and intraoperative photos depicts the heart's anatomy of a 4-year-old girl with type D Ebstein's anomaly (Carpentier's classification). Images (a) (b), and (c) show that the tricuspid valve leaflets are tethered to the right ventricle wall and image d shows that there is only a small hole-H communicating the atrialized to the functional right ventricle (with permission from reference [58]).*

### **7.6 Bidirectional Glenn procedure to improve postoperative cardiac output**

It is expected that some RV dysfunction will be evident early after the cone procedure due to RV wall damage related to surgical maneuvers superimposed on varying degrees of RV impairment from the Ebstein's malformation itself. Additionally, myocardial injury may be caused by the extended ischemic time required to perform this somewhat complex operation. With this in mind, we have routinely used a valved ASD that allows blood flow from the right to the left atrium, aiming to reduce RV preload and increase LV preload, thereby helping to prevent low cardiac output due to severe RV dysfunction in the early postoperative period. In most patients, the ASD stays functionally closed from the beginning of the postoperative course. However, approximately 10% of cases evolve with right-to-left blood shunting that can cause a substantial drop in oxygen saturation. In such cases, oxygen saturation usually increases in a few days as RV function improves. Additionally, the resulting RV

decompression may prevent excessive tension at the tricuspid valve, decreasing the risk of suture dehiscence and TV regurgitation.

In some studies, the problems related to postoperative RV dysfunction have been addressed by diverting the superior caval blood flow to the right pulmonary artery. Chauvaud et al. [59] used this bidirectional cavopulmonary shunt (BCPS)—also called the Glenn procedure—as an adjunctive procedure to Carpentier's operation in patients with Ebstein's anomaly and severe right ventricular dysfunction (36% of procedures). They reported that this combination of procedures led to improved results. Other studies have also reported the use of this technique to reduce RV preload in cases of severe RV dysfunction, thus significantly reducing mortality caused by RV failure [60, 61]. Quinonez et al. [62] also reported the creation of a BCPS as an adjunctive procedure with surgical treatment of Ebstein's anomaly in 14 patients from the Mayo Clinic (TV replacement in 13 and TV repair in 1). In most cases, this approach was planned in anticipation of RV failure, but it was also sometimes performed as a salvage procedure when faced with postoperative hemodynamic instability. Considering the serious clinical situation of the included patients, the study results were excellent with only one death, outlining the importance of this procedure for a subset of patients. Liu et al. [63] also reported the use of the BCPS procedure in addition to the cone operation in a series of young patients. This group applied BCPS procedure to 67% of patients with Ebstein's anomaly (20 of 30), which drew our attention. However, their series of young patients had good clinical outcomes at mid-term follow-up. We think this method can be used in children to improve pulmonary circulation in case of residual tricuspid regurgitation after the cone repair. We also believe that it is important to employ one of these two methods after the cone operation to prevent low postoperative cardiac output and to protect the dysfunctional RV from distension. We preferentially use the valved closure of ASD. Despite initial cyanosis in some patients and the possibility of paradoxical thromboembolism, RV dysfunction is completely or partially reversible with time and, consequently, oxygen saturation progressively improves [57]. While the BCPS has the advantage of providing better oxygenation, we do not routinely use it because it may be associated with pulsations of the head and neck veins and other complications [61]. In case of low oxygen saturation (<75%) we add a BCPS for older patients or a small (3.0-mm) modified Blalock-Taussig (BT) shunt. We tend to anticoagulated patients who present a dilated RV and/or right-to-left atrial shunting.

The cone procedure for reconstruction of the TV in Ebstein's malformation usually provides a full coaptation of the leaflets, resulting in effective and durable tricuspid regurgitation repair in the majority of patients. Therefore, its use has been expanded to patients who previously underwent other types of Ebstein's anomaly treatment.

#### **7.7 Surgical treatment in neonatal Ebstein's anomaly**

Despite recent medical advances, it remains difficult to manage critically ill neonates with Ebstein's anomaly. A multicenter study conducted at excellent hospitals reported that surgical or catheter interventions carried high mortality (30%) in newborns with critical Ebstein's anomaly [16]. Additionally, multivariable analysis showed that the lack of antegrade pulmonary valve flow or the presence of pulmonary regurgitation at the time of diagnosis were powerful hemodynamic risk indicators [16]. That study emphasized the necessity for careful surgical management of this group of patients.

Newborns with Ebstein's anomaly presenting a dependency on prostaglandins or mechanical ventilation, worsening cyanosis or heart failure, anatomic pulmonary

atresia, a circular shunt, will require surgical intervention during the neonatal period [7].

The primary cone repair of neonatal Ebstein's anomaly is a complex procedure due to the delicate valve tissues and the associated lung immaturity. It can be applied only to a small subgroup of older (over 2-week-old), and stable patients with a favorable TV morphology, such as a large and mobile anterior leaflet, a reasonably sized functional RV with good systolic function, and good pulmonary artery and valve anatomy [64]. In that situation, the procedure by an experienced surgeon would be indicated to correct a severe regurgitation that would limit the pulmonary flow and cause cyanosis. In a few situations, where the tricuspid valve presents more complex anatomy in patients with inadequate forward pulmonary flow, with cyanosis, but without expressive cardiomegaly, or septal impingement to the left ventricle, a PDA stent or a BT shunt can be the initial surgical approach. This stenting procedure has the goal to allow the child to develop the pulmonary circulation and the RV for the next step, which is the Cone procedure applied at 4 or 5 months, resulting in a biventricular repair.

However, the great majority of newborns with Ebstein's anomaly presenting with heart failure should be addressed with the Starnes procedure that, by decompressing the left ventricle and giving more space to the lungs, offers a better outcome for these very sick babies [65].

The surgical palliation with the Starnes procedure consists of excluding the malformed right ventricle with a fenestrated patch sewn at the anatomic level of the tricuspid valve annulus and creation of a systemic to pulmonary artery shunt to provide the pulmonary blood flow. This procedure allows the decompression of the malformed right ventricle, but also ameliorates the septal impingement to the left, with a significant effect on the systemic left ventricle, which reassumes the globular shape after the Starnes. Any pulmonary insufficiency should be contained, and the coronary sinus must stay on the atrial side of the patch to assure effective decompression of the right ventricle. The atrial communication is enlarged and a reduction atrioplasty opens space inside the chest for the lung development [66]. The modified Starnes procedure is adequate for neonates who are hemodynamically unstable, or even on ECMO support. It is usually successful and helps the patients to survive and to prepare them for other more definitive future procedures.

### **7.8 The Da Silva Cone repair after the Starnes procedure**

Although usually successful, the Starnes approach excludes the right ventricle from the pulmonary circulation. So, after the Starnes operation, these patients were traditionally committed to the single ventricle repair pathway [67], which leads to the undesirable long-term complications associated with Fontan palliation [68]. However, we have demonstrated that it is possible to rehabilitate the right ventricle after the Starnes procedure in patients with Ebstein's anomaly and pulmonary atresia, achieving 1.5 or two-ventricle repair [69]. We also have shown that in patients with fetal circular shunt physiology who underwent the Starnes procedure as a newborn, it is possible to rehabilitate the RV and the pulmonary valve, resulting in two-ventricle physiology [70], as demonstrated in **Figure 22**.

Bearing in mind that the cone repair can follow the Starnes procedure, we prefer to use a Gore-Tex patch to exclude the RV in the Starnes procedure, because it causes less adhesions, facilitating its taking down during the cone repair. Furthermore, this patch should be sutured above the TV annulus, and in the Todaro's ligament at the

#### **Figure 22.**

*Intraoperative images of the Da Silva cone repair after the Starnes procedure. (a) Exposure of the tricuspid valve, which is covered with the Starnes patch (SP). (b) Removal of the fenestrated PTFE patch, taking care not to damage the anterior leaflet of the tricuspid valve, which is adjacent to the patch. (c) Extensive tricuspid valve mobilization; this is initiated at the anterior leaflet (AL) hinge line and continues clockwise toward the inferior leaflet; here, the inferior papillary muscle is being cut. (d) A second incision is made near the anteroseptal commissure (arrow); the cut continues counterclockwise to mobilize the medial part of the anterior leaflet and the entire septal leaflet from their proximal attachments. The proximal detachment of the septal leaflet (SL) follows the dotted line. (e) The inferior leaflet is rotated medially, and a vertical interrupted suture unites it with the lateral aspect of the septal leaflet. The resulting cone-shaped structure is sutured to the anatomical tricuspid valve annulus, which completes the cone repair. SP = starnes patch, AL = anterior leaflet, SL = septal leaflet (with permission from reference [58]).*

#### **Figure 23.**

*Serial echocardiograms show cardiac evolution in a four-chamber view. (a, b) Preoperative image shows typical, severe Ebstein's anomaly morphology, with enlarged right heart chambers, and severe downward displacement of septal and inferior leaflets. The ventricular septum is shifted to the left, compressing the left ventricle. (c, d) Postoperative image after the Starnes procedure shows diastolic flow across the fenestration of the right ventricle exclusion patch (FP). Here, the ventricular septum (S) is shifted to the right (arrow); this reduces the area for the right ventricle and provides more space for the left ventricle, which increased in volume and assumed a globular shape. (e, f) Image acquired 3 weeks after biventricular repair shows the results of the Da Silva cone technique; the right ventricle is a good size, and the ventricular septum is in a well-balanced position. (e) The now anatomically positioned tricuspid valve presented good inflow and (f) mild to moderate regurgitation. AL = anterior leaflet of the tricuspid valve, RV = right ventricle, LV = left ventricle, FP = fenestrated polytetrafluoroethylene patch, and S = ventricular septum (Figure 23c with permission from reference [70].*

### *Ebstein's Anomaly DOI: http://dx.doi.org/10.5772/intechopen.104670*

septal area. These technical measures aim to facilitate the patch removal without damaging the TV leaflets or the atrioventricular node at the time of the Da Silva Cone procedure. In **Figure 23**, serial echocardiograms images demonstrate the cardiac evolution of a neonatal Ebstein submitted to the Starnes procedure and later to the Da Silva Cone repair.
