Pulmonary valve preservation and restoration strategies for repair of 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.

Surgical Strategies for Preservation of Pulmonary Valve Function in a Radical Operation for Tetralogy of Fallot: A Systematic Review and Meta-Analysis

Objective

To evaluate the efficacy and safety of different surgical strategies to preserve pulmonary valve function. Surgical procedures evaluated include intraoperative balloon pulmonary valvuloplasty (IBPV), pulmonary valve reconstruction, and commissurotomy and pulmonary cusp augmentation (PCA) in patients who underwent a radical operation for Tetralogy of Fallot (ToF).

Materials and Methods

The five databases searched in the current study included the Cochrane Library, PubMed, China National Knowledge Infrastructure, VIP, and WanFang data. A systematic search for control trials was performed in each database from the start date of each database until December 2021. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of included studies.

Results

A total of 15 retrospective studies with a total number of 1,396 participants were included in this study. In subgroup 1 (IBPV vs. TAP), patients undergoing IBPV had a less degree of regurgitation at 1-2 years after the surgery. The reintervention rate increased in the IBPV group at 5 years. In subgroup 2 (pulmonary valve reconstruction vs. TAP), the degree of regurgitation decreased in the pulmonary valve reconstruction group at 1 month after the surgery. In subgroup 3 (valve-sparing operation vs. TAP), the comparison demonstrated decreased rates for surgical mortality and reintervention at 5-10 years after the surgery.

Conclusion

We proposed that pulmonary valve function in a radical operation for ToF was preserved. IBPV, pulmonary valve reconstruction, and commissurotomy and PCA can be performed during the surgical procedure based on the developmental status and anatomical characteristics of the right ventricular outflow tract (RVOT), pulmonary valve, and pulmonary artery.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42022300987].

Native Pulmonary Valve Restoration Late Following Transannular Patch Repair of Tetralogy of Fallot

We present a surgical case of native pulmonary valve (PV) restoration in a 16-year-old boy with a previous history of transannular patch repair of tetralogy of Fallot in infancy. The PV was restored by approximation of split anterior commissure in the presence of developed and pliable leaflets well preserved after initial surgery. Postoperative echocardiogram showed a competent valve with peak velocity of 2.8 m/s. At six-week follow-up, the patient remained well, and echocardiogram demonstrated a competent PV with decreased velocity of 2.1 m/s across it. We encourage a mindful preservation of PV leaflets whenever it is possible at time of initial repair to implement this relatively easy operation to restore PV function later in life.

Architecture matters: Tissue preservation strategies for tetralogy of Fallot repair

BACKGROUND

Great variability exists in repair strategies for the tetralogy of Fallot. While transannular patching, as introduced by Kirklin, was a breakthrough for primary repair, pulmonary regurgitation and a need for reoperation have led to the development of methods that preserve the natural morphology of the right ventricular outflow tract.

METHODS

State-of-the-art details of tetralogy of Fallot repair are explained from the standpoint of architectural preservation, especially with regard to sparing native tissue such as the annulus, valve, or infundibulum. Particular attention is given to the latest technical details of each approach, benefits and disadvantages, and any long-term data available.

RESULTS

The choice of procedure is complex and unique to each case as transannular patching alone may carry long-term pulmonary risks. Modifications that spare the annulus, valves, or infundibulum may thus be essential as preservation of natural morphology has resulted in excellent mid-term results.

CONCLUSIONS

The complexity of tetralogy of Fallot repair demands constant attention to clinical presentation and vigilance against long-term sequelae. Techniques will continue to improve over time as long-term data guides the refinement of these innovative surgical methods.

Early results of neopulmonary valve creation technique using right atrial appendage tissue

INTRODUCTION

Various valve repair techniques have been described for prevention of pulmonary insufficiency (PI) during right ventricular outflow tract (RVOT) reconstruction with transannular patch. Herein, we present the early results of an alternative technique of neopulmonary valve reconstruction using right atrial appendage (RAA) tissue.

METHODS

Between October 2019 and December 2019, 12 patients with tetralogy of fallot (TOF) (n = 10), TOF-absent pulmonary valve (n = 1) and intact ventricular septum-pulmonary atresia (n = 1) underwent RVOT reconstruction with neopulmonary valve that was created using RAA tissue. Median age and weight of patients were 9.9 months (5 months-14 years) and 9.8 kg (6.2-47), respectively.

RESULTS

No mortality or major events developed. Postoperative echocardiography revealed none/trace PI in 11 patients and mild PI in 1 patient. Median right ventricle/left ventricle ratio was 0.46 (0.35-0.65) and RVOT gradient was 20 mm Hg (0-30). Median cardiopulmonary bypass and aortic clamping times were 121 minutes (81-178) and 94 minutes (59-138), respectively. Operative times revealed statistically significant learning curve pattern in terms of cardiopulmonary bypass (r² = .568; P = .005) and aortic clamping times (r²  = .635; P = .002). Median ventilation time, intensive care unit stay, and the length of hospital stay were 6 hours (2-48), 1 days (1-5), and 7 days (4-10), respectively. Longer perfusion time was not correlated with postoperative times. At median 6 months, echocardiography showed none/trivial PI in 11 patients and mild PI in one patient.

CONCLUSION

Early results showed that neopulmonary valve reconstruction using the RAA tissue may provide a reasonable alternative for RVOT reconstruction with transannular patch. But long-term results are needed.

Current outcomes and treatment of tetralogy of Fallot

Tetralogy of Fallot (ToF) is the most common type of cyanotic congenital heart disease. Since the first surgical repair in 1954, treatment has continuously improved. The treatment strategies currently used in the treatment of ToF result in excellent long-term survival (30 year survival ranges from 68.5% to 90.5%). However, residual problems such as right ventricular outflow tract obstruction, pulmonary regurgitation, and (ventricular) arrhythmia are common and often require re-interventions. Right ventricular dysfunction can be seen following longstanding pulmonary regurgitation and/or stenosis. Performing pulmonary valve replacement or relief of pulmonary stenosis before irreversible right ventricular dysfunction occurs is important, but determining the optimal timing of pulmonary valve replacement is challenging for several reasons. The biological mechanisms underlying dysfunction of the right ventricle as seen in longstanding pulmonary regurgitation are poorly understood. Different methods of assessing the right ventricle are used to predict impending dysfunction. The atrioventricular, ventriculo-arterial and interventricular interactions of the right ventricle play an important role in right ventricle performance, but are not fully elucidated. In this review we present a brief overview of the history of ToF, describe the treatment strategies currently used, and outline the long-term survival, residual lesions, and re-interventions following repair. We discuss important remaining challenges and present the current state of the art regarding these challenges.

Surgery for Tetralogy of Fallot in Adults: Early Outcomes

Objective

To study the in-hospital outcome of adult patients who had undergone surgical repair for Tetralogy of Fallot.

Methods

A retrospective descriptive study was conducted at the Punjab Institute of Cardiology searching the hospital records. All those adult patients who had undergone repair for Tetralogy of Fallot from January 2012 to December 2014 were included in the study. All the patients were operated by the same surgical team. Patients who underwent primary repair as well as those with previous palliative procedures were included in the study. Thirty days outcome was studied by recording variables from the database. Data was analysed using Statistical Package for Social Sciences version 16.

Results

A total of 80 patients was included in the study, in which there were 48 (60%) male patients and 32 (40%) female patients. Mean age was 21±0.21 years. Those with previous palliation were 15 (18.75%). The associated problems observed were: atrial septal defect 27 (33.75%), right aortic arch 30 (37.5%), patent ductus arteriosus 6 (7.5%) and double outlet right ventricle 3 (3.75%). In-hospital mortality recorded was 7 (8%). Postoperative complications encountered were low cardiac output syndrome 9 (11.25%), pleural effusion requiring tapping 3 (3.75%), reoperation for bleeding 3 (3.8%), pulmonary regurgitation (moderate to severe) 20 (25%) which occurred in the transannular patch group only and atrial arrhythmia 4 (5%).

Conclusion

A large number of adult patients are still operated for tetralogy of Fallot in Pakistan. With increasing experience in the technique the mortality and morbidity is comparable to international literature.

Pulmonary Valve Repair for Patients With Acquired Pulmonary Valve Insufficiency

BACKGROUND

Pulmonary valve (PV) insufficiency is often an acquired condition after treatment for pulmonary stenosis. It is recognized that PV insufficiency has serious deleterious effects. Although surgical replacement of the PV is efficacious, artificial valves inevitably fail and require re-intervention. The purpose of this study was to summarize our experience with PV repair in patients with acquired PV insufficiency.

METHODS

This was a retrospective review of 16 patients with marked PV insufficiency who underwent PV repair. Thirteen of these patients were born with tetralogy of Fallot (TOF) and had undergone a previous transannular patch repair. Three patients were born with critical pulmonary stenosis and had a surgical valvotomy or balloon valvuloplasty.

RESULTS

The 13 patients with TOF had resection of their previously placed transannular patch with re-approximation of the anterior commissure. All 13 patients experienced a marked reduction in the degree of pulmonary insufficiency. None of these patients have experienced any increase in insufficiency during follow-up. The 3 patients with critical pulmonary stenosis had a variety of pathologic findings identified at the surgical procedure. One patient had a large gap between a commissure and underwent closure of that commissure. The second and third patients had torn leaflets repaired with pericardial and Gore-Tex patches (Gore, Inc, Flagstaff, AZ). The degree of PV insufficiency was decreased to mild in all 3 patients. However, 2 of these 3 patients have subsequently had an increase in the degree of pulmonary insufficiency.

CONCLUSIONS

Patients with TOF who underwent a previous transannular patch may be candidates for bicuspidization of their native PV, and the results of this procedure have been quite stable at follow-up. PV repair for torn leaflets was effective in the short term but was less stable over time.