Prosthetic reconstruction of bicuspid pulmonary valve in tetralogy of Fallot

Evolution of Pulmonary Valve Management During Repair of Tetralogy of Fallot: A 14-year Experience

BACKGROUND

The optimal repair strategy for tetralogy of Fallot remains controversial. This report presents a 14-year evolution of management of the pulmonary valve (PV) from transannular patch to valve-sparing repair to neovalve creation using living right atrial appendage tissue.

METHODS

A retrospective review of 172 consecutive patients undergoing complete repair for TOF between January 2007 and June 2021 was performed. Clinical and follow-up data were analyzed by repair group. Neopulmonary valve (NPV) creation using right atrial appendage tissue was introduced in 2019. Failure of valve-sparing repair was defined as needing reintervention for recurrent right ventricular outflow tract obstruction (RVOTO).

RESULTS

Median age and weight at repair were 4.9 months and 6 kg, respectively. Median preoperative PV size and z-score were 6.4 mm (5.2-8.3 mm) and -3.2 (-4.1 to -2.1), respectively. Patients who underwent valve-sparing repair had larger PV size and z-score compared with patients who underwent transannular patch procedures (8 mm vs 5.6 mm; -2.1 vs -3.2; both P < .001). There were no hospital mortalities. Overall follow-up was 44 months. At last follow-up, 10% of patients who underwent valve-sparing repair had repeat intervention for recurrent RVOTO. Patients who had failed valve-sparing repair had significantly lower PV z-scores (-2.6 vs -1.9; P = .01). An NPV was used in 8 patients with a median PV z-score of -4 (-4.7 to -3.9). At 6 months, 6 patients (75%) had mild or trivial pulmonary insufficiency after NPV placement.

CONCLUSIONS

Repair of tetralogy of Fallot is a safe operation with excellent outcomes. Valve-sparing repair avoids right ventricular dilation but may fail for RVOTO at a PV z-score <-2. NPV creation offers an alternative option in patients with a small PV.

End-diastolic forward flow in repaired tetralogy of Fallot: Mid-term outcomes from a single center

Background

Pulmonary arterial end-diastolic forward flow (EDFF) following repaired tetralogy of Fallot (rTOF) is recognized as right ventricular (RV) restrictive physiology, which is closely related to poor prognosis. This study sought to review mid-term experience and investigate the risk factors of EDFF in the rTOF patients.

Methods

From September 2016 to January 2019, 100 patients (age < 18 years old) who underwent complete tetralogy of Fallot (TOF) repair were enrolled and were divided into EDFF group (n = 52) and non-EDFF group (n = 48) based on the presence of postoperative EDFF. Elastic net analysis was performed for variable selection. Univariate and multivariate logistic analyses were used to analyze the correlation between risk factors and EDFF.

Results

End-diastolic forward flow group had lower systolic blood pressure (P = 0.037), diastolic blood pressure (P = 0.027), and higher vasoactive-inotrope score within 24 h after surgery (P = 0.022) than non-EDFF group. Transannular patch (TAP) was an independent predictor of postoperative EDFF [P = 0.029, OR: 2.585 (1.102∼6.061)]. Patients were followed up for a median of 2.6 years [interquartile range (IQR) 1.6] after the first TOF repair. During follow-up, the prevalence of the EDFF was lower in those with pulmonary valve (PV) reconstructions than that in those undergoing patch enlargement without PV reconstructions in the primary TOF repair (P < 0.001).

Conclusion

End-diastolic forward flow was associated with TAP. Patients with EDFF might have a transient hemodynamic instability in the early postoperative period. PV reconstructions in the TOF repair might reduce the incidence of EDFF in the mid-term follow-up.

The Predicament of Surgical Correction of Tetralogy of Fallot

Surgery for tetralogy of Fallot has a long history, which may be described as both a success story and a failure story. It is a success story because prognosis without surgery is very poor, but surgery makes it possible for affected babies to reach adulthood and lead productive lives. It is a failure story, however, since we still cannot cure this condition; we can only palliate it as illustrated in the sobering long-term outcome of affected patients. In this review article, we aim to explore the reason for this failure. This may be summed up in terms of the nature of the obstruction to the right ventricular outflow tract, which characterizes this malformation and must be relieved. This obstruction has several possible components, but none may be eliminated without harming the ventricle. There seems to be no 'extra' muscle band in tetralogy of Fallot that may be dispensed with without undermining ventricular function; every muscle band that is there should be there, just like in the normal heart, except that these are thicker than normal and somewhat displaced in tetralogy of Fallot, thus narrowing the right ventricular outflow tract. Consequently, ventricular function deteriorates with every muscle band that is cut, just like in the normal heart. We have to harm the heart in order to repair it. Every repaired Fallot is inevitably a damaged heart. Consequently, repair of this condition cannot be curative at present; it is palliative surgery.

Surgical repair of tetralogy of Fallot using autologous right atrial appendages: short- to mid-term results

OBJECTIVES

The prevention of pulmonary insufficiency (PI) is a crucial part of the tetralogy of Fallot repair. Many techniques have been introduced to construct valves from different materials for the right ventricular outflow tract, including the most commonly constructed monocusp valves. We are introducing a new bicuspid valve made intraoperatively using the autologous right atrial appendage (RAA) to prevent PI in these patients.

METHODS

The RAA valve was constructed and used in 21 patients with tetralogy of Fallot. The effective preservation of the native valve was impossible in all patients because of either a severe valve deformity or a small annulus. The RAA valve was created after ventricular septal defect closure and right ventricular outflow tract myectomy and was covered with a bovine transannular pericardial patch. The perioperative data were evaluated, and the echocardiography results were assessed immediately after operations and in follow-up with a median of 10.5 months. The data were retrospectively compared with 10 other patients with similar demographic data but with only transannular patches.

RESULTS

The mean age of the patients was 13.3 months. No mortality or related morbidity occurred after repair using the RAA valve. The PI severity early after the operation was trivial or no PI in 18 patients, and mild PI was observed in 3 patients, which progressed to moderate PI in one of them in the mean 12-month follow-up period. Fifteen patients had mild or no pulmonary stenosis, while moderate pulmonary stenosis was observed in 6 others. Compared with the other 10 patients with only transannular patches, the RAA valve patients had prolonged operative and clamping times, but no difference in postoperative course and shorter hospital stays. The degree of PI was, of course, significantly less in the RAA valve patients, but pulmonary stenosis was the same.

CONCLUSIONS

The RAA valve construction is a safe and effective technique to prevent PI after the tetralogy of Fallot repair, at least in terms of short- and mid-term results. A longer follow-up period is needed to confirm if this new valve can eliminate or significantly delay the need for pulmonary valve replacement in these patients.

Adult tetralogy repair: factors affecting early outcome in the current era

Background

The benefits of surgical correction of adult tetralogy of Fallot are well known. The current recommendation is for total correction regardless of age. This study analyzed perioperative factors affecting early outcome after corrective surgery in adulthood in the current era.

Methods

This was a retrospective chart review of 40 consecutive patients over 18 years of age who underwent total correction of tetralogy of Fallot from September 2006 to June 2013. Patients with pulmonary atresia and absent pulmonary valve were excluded. The mean age at surgery was 26.60 ± 8.69 years (range 18–49 years).

Results

The mean intensive care unit stay was 3.30 ± 2.29 days (range 0.75–12 days) and hospital stay was 9.97 ± 3.39 days (range 7–22 days). Mortality was 5% (2/40). Multiple parameters indicating immediate postoperative outcomes and their relationships to selected pre-, intra-, and postoperative factors were analyzed. Multivariate analysis showed that postoperative right ventricular dysfunction had a significant influence on mortality ( p < 0.001) and hospital stay ( p = 0.01). Performing zero-balance ultrafiltration decreased the need for renal replacement therapy ( p = 0.034), duration of ventilation ( p = 0.009), incidence of low cardiac output ( p = 0.006), intensive care unit stay ( p = 0.01), and hospital stay ( p = 0.009).

Conclusions

Total correction of tetralogy of Fallot is a safe option for presentations as late as adulthood. The protective effect of zero-balance ultrafiltration on postoperative morbidity needs to be reassessed in larger studies.

Optimal Use of Z-Scores to Preserve the Pulmonary Valve Annulus During Repair of Tetralogy of Fallot

Objective:

The size of the pulmonary annulus measured as a z-score is often used to determine when to insert a transannular patch (TAP). Multiple “cutoffs” are quoted in the literature; this could lead to inappropriate insertion. We aimed to determine whether the use of z-scores derived from different populations may have contributed to the varied “cutoffs” quoted.

Methods:

PubMed was searched using the terms: “tetralogy,” “Fallot,” “transannular,” “patch,” “mortality,” and “death.” Studies published between January 1, 2005, and October 5, 2017, were included; studies without participants under the age of 18 years and studies that did not describe the operative procedure were excluded.

Results:

Of 52 papers retrieved, 19 were included representing 2,500 repaired patients; 1,371 (54.8%) had a TAP. Five (26.3%) papers representing 638 patients (25.5%) quoted a z-score “cutoff” and what data set was used; “cutoffs” ranged from −2 to −4 and were derived from 2 different data sets. Three studies quoted a data set that has been shown in previous work to be problematic; the only quoted “cutoffs” of −4 were from two of these studies.

Conclusions:

Surprisingly few (26.3%) studies mention what pulmonary annulus size “cutoff” was used to decide when to insert a TAP. Z-scores derived from different populations were used by different studies and it is possible that this may have contributed to the varied “cutoffs’ quoted. Recommendations to perform valve-sparing surgery in pulmonary annuli as small as −4 may not be warranted. Future papers should record “cutoffs” employing recommended z-score data set.