Valve-sparing repair with intraoperative balloon dilation in tetralogy of Fallot: Midterm results and therapeutic implications

Comparing clinical and echocardiographic outcomes following valve-sparing versus transannular patch repair of tetralogy of Fallot: a systematic review and meta-analysis

OBJECTIVES

Transannular patch (TAP) repair of tetralogy of Fallot (ToF)relieves right ventricular tract obstruction but may lead to pulmonary regurgitation. Valve-sparing (VS) procedures can avoid this situation, but there is a potential for residual pulmonary stenosis. Our goal was to evaluate clinical and echocardiographic outcomes of TAP and VS repair for ToF.

METHODS

A systematic search of the PubMed, Embase, Scopus, Cochrane Central Register of Controlled Trials and Web of Science databases was carried out to identify articles comparing conventional TAP repair and VS repair for ToF. Random-effects models were used to perform meta-analyses of the clinical and echocardiographic outcomes.

RESULTS

Forty studies were included in this meta-analysis with data on 11 723 participants (TAP: 6171; VS: 5045). Participants who underwent a VS procedure experienced a significantly lower cardiopulmonary bypass time [mean difference (MD): -14.97; 95% confidence interval (CI): -22.54, -7.41], shorter ventilation duration (MD: -15.33; 95% CI: -30.20, -0.46) and shorter lengths of both intensive care unit (ICU) (MD: -0.67; 95% CI: -1.29, -0.06) and hospital stays (MD: -2.30; 95% CI: [-4.08, -0.52). There was also a lower risk of mortality [risk ratio: 0.40; 95% CI: (0.27, 0.60) and pulmonary regurgitation [risk ratio: 0.35; 95% CI: (0.26, 0.46)] associated with the VS group. Most other clinical and echocardiographic outcomes were comparable in the 2 groups.

CONCLUSIONS

This meta-analysis confirms the well-established increased risk of pulmonary insufficiency following TAP repair while also demonstrating that VS repairs are associated with several improved clinical outcomes. Continued research can identify the criteria for adopting a VS approach as opposed to a traditional TAP repair.

Association of tetralogy of Fallot and complete atrioventricular canal: a single-centre 40-year experience

OBJECTIVES

Outcome data in tetralogy of Fallot (ToF) and complete atrioventricular canal (CAVC) are limited. We report our experience for over 40 years in this patient population.

METHODS

Single-centre, retrospective analysis of patients who underwent surgical repair with the diagnosis of ToF-CAVC from 1979 to 2022, divided into 2 different periods and compared.

RESULTS

A total of 116 patients were included: 1979-2007 (n = 61) and 2008-2021 (n = 55). Balanced CAVC (80%) and Rastelli type C CAVC (81%) were most common. Patients in the later era were younger (4 vs 14 months, P < 0.001), fewer had trisomy 21 (60% vs 80%, P = 0.019) and fewer had prior palliative prior procedures (31% vs 43%, P < 0.001). In the earlier era, single-patch technique was more common (62% vs 16%, P < 0.001), and in recent era, double-patch technique was more common (84% vs 33%, P < 0.001). In the earlier era, right ventricular outflow tract was most commonly reconstructed with transannular patch (51%), while in more recent era, valve-sparing repairs were more common (69%) (P < 0.001). In-hospital mortality was 4.3%. The median follow-up was 217 and 74 months for the first and second eras. Survival for earlier and later eras at 2-, 5- and 10-year follow-up was (85.1%, 81.5%, 79.6% vs 94.2%, 94.2%, 94.2% respectively, log-rank test P = 0.03).

CONCLUSIONS

The surgical approach to ToF-CAVC has evolved over time. More recently, patients tended to receive primary repair at younger ages and had fewer palliative procedures. Improved surgical techniques allowing for earlier and complete repair have shown a decrease in mortality, more valve-sparing procedures without an increase in total reoperations. Presented at the 37th EACTS Annual Meeting, Vienna, Austria.

Optimal Surgical Management of Tetralogy of Fallot

Tetralogy of Fallot with pulmonary stenosis has a diverse clinical spectrum with the degree of right ventricular outflow tract obstruction (RVOTO) and size of the branch pulmonary arteries driving clinical management. Optimal surgical management involves consideration of patient clinical status and degree and location (subvalvar, valvar, and supravalvar) of RVOTO. Timing of repair requires multidisciplinary decision-making and complete surgical repair with relief of RVOTO by either transannular patch or valve sparing repair techniques. The central goals of contemporary surgical management of tetralogy of Fallot incorporate maximizing survival, minimizing reintervention, and preserving right ventricular function across the lifespan.

Considerations in Timing of Surgical Repair in Tetralogy of Fallot

Certain aspects of the treatment of tetralogy of Fallot (TOF) repair remain controversial. The optimal timing of the elective repair of asymptomatic patients and the ideal strategy for managing symptomatic neonates and infants with TOF are still debated despite years of experience in TOF treatment. In this article, we discuss why a surgical correction at 3-6 months of age is likely the ideal time frame for the elective repair of TOF. We also elaborate on our strategy for managing symptomatic neonates and infants with TOF and why we prefer an early single-stage primary repair.

Systematic Analysis of PTFE Monocusp Leaflet Design in a Patient-Based 3D in-Vitro Model of Tetralogy of Fallot

PURPOSE

Pulmonary valve (PV) monocusp reconstruction in transannular patch (TAP) right ventricular outflow tract (RVOT) repair for Tetralogy of Fallot has variable clinical outcomes across different surgical approaches. The study purpose was to systematically evaluate how monocusp leaflet design parameters affect valve function in-vitro.

METHODS

A 3D-printed, disease-specific RVOT model was tested under three infant physiological conditions. Monocusps were sewn into models with the native main pulmonary artery (MPA) forming backwalls that constituted 40% and 50% of the reconstructed circumference for z-score zero PV annulus and MPA diameters (native PV z-score - 3.52 and - 2.99 for BSA 0.32m2). Various leaflet free edge lengths (FEL) (relative to backwall), positions (relative to PV STJ), and scallop depths were investigated across both models. Pressure gradient, regurgitation, and coaptation were analyzed with descriptive statistics and regression models.

RESULTS

Increasing FEL beyond 100% of the MPA backwall decreased gradient but mildly increased regurgitation to a peak of 25%. Positioning the free edge 2 mm past the STJ mildly increased gradient for each FEL without significantly changing regurgitation compared to STJ placement. Scalloping leaflets trivially affected performance. Pre-folding leaflets improved mobility and slightly reduced gradient.

CONCLUSIONS

Balancing gradient, regurgitation, and oversizing for growth, a set of leaflet designs have been selected for pre-clinical evaluation. Designs with leaflet widths 140-160% in the 40% backwall model (110-120% in the 50% backwall), positioned at or 2 mm past the STJ, demonstrated the best results. The next stage of ex-vivo testing will additionally consider native RVOT distensibility, native leaflet interactions, and TAP characteristics.

Influencing factors of prognosis in children with pulmonary atresia with intact ventricle septum after transthoracic balloon dilation of pulmonary valve and construction of a nomograph prediction model

This study aimed to identify factors that affect the prognosis of children with pulmonary valve atresia and intact ventricular septum treated with transthoracic balloon dilation of the pulmonary valve. The study included 148 participants who were followed up for 5 years. Of these, 10 died, while 138 survived. Independent sample t-test and χ2 test were used to analyze clinical data of children in the death and survival groups. It was found that height, weight, body surface area, arterial oxygen saturation, degree of tricuspid regurgitation, pulmonary valve cross valve pressure difference, ICU length of stay, length of stay, reoperation intervention, and complications were statistically significant (P<0.05). ROC curve analysis of the measurement indicators with statistically significant differences showed that height, weight, body surface area, arterial oxygen saturation, ICU length of stay, and length of stay had AUCs ranging from 0.723 to 0.870. Logistic regression analysis revealed that the degree of tricuspid regurgitation, pulmonary valve cross valvular pressure difference, ICU length of stay, reoperation intervention, and complications were independent risk factors that affect the prognosis of patients with PA/IVS undergoing transthoracic balloon dilation of pulmonary valve. The study proposed a nomogram prediction model using R language software 4.0 "rms" package, which was validated using calibration curve and decision curve. The model had a C-index of 0.667 (95% CI: 0.643-0.786) and high degree of fit. This study provides clinicians with a prediction model to identify children with poor prognosis after treatment with transpulmonary valve balloon dilatation.           .

The American Association for Thoracic Surgery (AATS) 2022 Expert Consensus Document: Management of infants and neonates with tetralogy of Fallot

OBJECTIVE

Despite decades of experience, aspects of the management of tetralogy of Fallot with pulmonary stenosis (TOF) remain controversial. Practitioners must consider newer, evolving treatment strategies with limited data to guide decision making. Therefore, the TOF Clinical Practice Standards Committee was commissioned by the American Association for Thoracic Surgery to provide a framework on this topic, focused on timing and types of interventions, management of high-risk patients, technical considerations during interventions, and best practices for assessment of outcomes of the interventions. In addition, the group was tasked with identifying pertinent research questions for future investigations. It is recognized that variability in institutional experience could influence the application of this framework to clinical practice.

METHODS

The TOF Clinical Practice Standards Committee is a multinational, multidisciplinary group of cardiologists and surgeons with expertise in TOF. With the assistance of a medical librarian, a citation search in PubMed, Embase, Scopus, and Web of Science was performed using key words related to TOF and its management; the search was restricted to the English language and the year 2000 or later. Articles pertaining to pulmonary atresia, absent pulmonary valve, atrioventricular septal defects, and adult patients with TOF were excluded, as well as nonprimary sources such as review articles. This yielded nearly 20,000 results, of which 163 were included. Greater consideration was given to more recent studies, larger studies, and those using comparison groups with randomization or propensity score matching. Expert consensus statements with class of recommendation and level of evidence were developed using a modified Delphi method, requiring 80% of the member votes with 75% agreement on each statement.

RESULTS

In asymptomatic infants, complete surgical correction between age 3 and 6 months is reasonable to reduce the length of stay, rate of adverse events, and need for a transannular patch. In the majority of symptomatic neonates, both palliation and primary complete surgical correction are useful treatment options. It is reasonable to consider those with low birth weight or prematurity, small or discontinuous pulmonary arteries, chromosomal anomalies, other congenital anomalies, or other comorbidities such as intracranial hemorrhage, sepsis, or other end-organ compromise as high-risk patients. In these high-risk patients, palliation may be preferred; and, in patients with amenable anatomy, catheter-based procedures may prove favorable over surgical palliation.

CONCLUSIONS

Ongoing research will provide further insight into the role of catheter-based interventions. For complete surgical correction, both transatrial and transventricular approaches are effective; however, the smallest possible ventriculotomy should be utilized. When possible, the pulmonary valve should be spared; and if unsalvageable, reconstruction can be considered. At the conclusion of the operation, adequate relief of the right ventricular outflow obstruction should be confirmed, and identification of a significant fixed anatomical obstruction should prompt further intervention. Given our current knowledge and the gaps identified, we propose several key questions to be answered by future research and potentially by a TOF registry: When to palliate or proceed with complete surgical correction, as well as the ideal type of palliation; the optimal surgical approach for complete repair for the best long-term preservation of right ventricular function; and the utility, efficacy, and durability of various pulmonary valve preservation and reconstruction techniques.

Fate of the Right Ventricular Outflow Tract Following Valve-Sparing Repair of Tetralogy of Fallot

Valve-sparing repair (VSR) of tetralogy of Fallot (TOF) tends to result in higher residual right ventricular outflow tract (RVOT) gradients. We evaluated the progression and clinical implications of RVOT gradients following VSR of TOF. Demographic, clinical, and operative data were retrospectively collected from consecutive TOF patients who underwent VSR at our institution between 01/2010 and 06/2021. RVOT gradient, pulmonary valve annulus (PVA) diameter and Boston Z-scores were recorded from serial echocardiograms. Data are presented as median and interquartile range or number and percentage. A total of 156 children (boys 92, 59%) underwent VSR at 6.5 (4.9-8.4) months of age and 6.6 kg (5.6- 7.7) weight. There was 1 (0.6%) operative mortality. The remaining 155 patients were followed for 69.4 months (4-106.2). RVOT gradient was 2.4m/s (1.7-2.9) at discharge. It transiently increased, then declined and stabilized during follow-up. PVA Z-score was -1.7 (-3.1 to 0.5) at discharge and 'grew' to -0.8 (-1.7 to 0.4) at last follow-up. Freedom from RVOT re-intervention was 97%, 94% and 91% at 1, 5 and 10-year follow-up. Among 67 (43%) patients with PVA Z-score < -2, a similar RVOT gradient pattern was observed and freedom from RVOT re-intervention was 97%, 95% and 95% at 1, 5 and 8-year follow-up. Following VSR of TOF, RVOT gradients transiently increase and then fall as PVA growth catches up, resulting in durable intermediate outcomes. Patients with PVA Z-score < -2 demonstrated a similar pattern of hemodynamics in the RVOT and excellent freedom from reintervention.

When do patients with Tetralogy of Fallot need a transannular patch

OBJECTIVES

The objective of this study was to evaluate the predictive value of main pulmonary artery (MPA) Z score, pulmonary valve annulus (PVA) prop, great aortic valve annulus (GA) ratio, PVA index (PAI), and PVA area index (PAAI) indicators in patients with Tetralogy of Fallot (TOF) and whether or not to undergo transannular patch (TAP).

METHODS

A retrospective analysis was performed on the clinical data of 263 patients with TOF who underwent radical operations from 2010 to 2021 at Beijing Children's Hospital. Sixteen cases were excluded, and 247 cases (male/female = 155/92) were included in this study. Based on whether TAP was selected intraoperatively, the patients were divided into the TAP group (82/247) and the non-TAP group (165/247). The diameter of the PVA, the aortic valve annulus, and the MPA were measured by echocardiography, and the PVA Z score, MPA Z score, PVA prop, GA ratio, PAI, and PAAI indexes were calculated, and statistical analysis was carried out.

RESULTS

The PVA Z score, MPA Z score, PVA prop, GA ratio, PAI, and PAAI of the TAP group were lower than those of the non-TAP group (p < .0001, p < .0001, p < .0001, p < .0001, p < .0001, and p < .0001). Receiver-operating curve analysis showed that the cut-off value of PVA Z score was -1.96 (area under the curve [AUC]: 0.822; 95% confidence interval [CI]: 0.769-0.874); the cut-off value of MPA Z score was -1.04 (AUC: 0.778; 95% CI: 0.711-0.845); the cut-off value of PVA prop was 0.37 (AUC: 0.812; 95% CI: 0.751-0.874); the cut-off value of GA ratio was 0.64 (AUC: 0.812; 95% CI: 0.750-0.874); the cut-off value of PAI is 0.78 (AUC: 0.812; 95% CI: 0.750-0.874); and the cut-off value of PAAI is 0.4 (AUC: 0.812; 95% CI: 0.750-0.874). Pulmonary valve bicuspid malformation is one reason why predictive models fail to predict the possible avoidance of TAP. Pearson's correlation and linear regression analysis showed that PAI had the strongest correlation with PVA Z score, followed by that between PVA prop and PVA Z score, and the weakest correlation between PAAI and PVA Z score.

CONCLUSIONS

PVA prop, GA ratio, PAI, and PAAI can well predict TAP selection, and the measurement is simple and convenient. Compared with PVA Z score, they are not hindered by other confounding factors, and can well replace the application value of PVA Z score in TAP prediction. The predictive efficacy of PAI and PVA prop is numerically better than the GA ratio, and PAAI, PAI, and PVA prop combined with MPA Z score can improve the predictive value of PAI and PVA prop, respectively. Although various echocardiographic parameters can be used as indicators to predict surgical approach in patients with TOF, PV morphology and tissue characteristics should also be considered.

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].

Pulmonary valve preservation during tetralogy of Fallot repair: midterm functional outcomes and risk factors for pulmonary regurgitation

OBJECTIVES

Many centres have recently adopted pulmonary valve (PV) preservation (PVP) during tetralogy of Fallot (ToF) repair. We sought to identify the midterm functional outcomes and risk factors for pulmonary regurgitation after this procedure.

METHODS

All patients undergoing PVP during transatrial-transpulmonary repair for ToF with PV stenosis at our institution between January 2007 and December 2020 were reviewed.

RESULTS

Overall, 73 patients were included. At the index surgery, the body surface area was 0.31 ± 0.04 m2, the age was 4.9 ± 2.9 months and the preoperative PV z-score was -3.02 ± 1.11. At a mean follow-up of 5.3 ± 2.7 years, the fractional area change of the right ventricle (RV) was 47.1 ± 5.2%, and the tricuspid annular plane systolic excursion z-score was -3.31 ± 1.89%. The 5-year freedom from moderate/severe PV regurgitation was 61.3% [95% confidence interval (CI): 48, 73%]. There was a significant correlation between RV function and moderate/severe PR at follow-up (R2: 0.08; P = 0.03). A comparison with a group of patients undergoing a transannular patch procedure (N = 33) showed superior outcomes for patients with PVP. The preoperative PV z-score and the degree of PR at discharge were risk factors for the early development of moderate/severe PR at follow-up [hazard ratio (HR): 0.64; 95% CI: 0.48, 0.86, P = 0.01 and HR: 2.31; 95% CI: 1.00, 5.36, P = 0.04, respectively]. A preoperative PV annulus z-score ≤ -2.85 was found to be predictive for moderate/severe PR at 5 years after PVP (HR: 2.56; 95% CI: 1.31, 5.01, P = 0.002).

CONCLUSIONS

A pulmonary valve preservation strategy during tetralogy of Fallot repair should always be attempted. However, a preoperative PV annulus z-score < -2.85 and moderate/severe regurgitation upon discharge are risk factors for midterm pulmonary regurgitation.

Clinical Application of Individualized Pulmonary Bi-Orifice for the Reconstruction of Right Ventricular Outflow Tract in Tetralogy of Fallot

Objective: The study aims to establish a new method in the Tetralogy of Fallot (ToF) called the pulmonary valve bi-orifice method (pulmonary annular sparing with an individualized autologous pericardial patch; thus, two orifices are formed at the level of the pulmonary valve annulus) to reconstruct the right ventricular outflow tract (RVOT).

Methods: A retrospective analysis of 128 TOF patients from October 2009 to June 2018 with severe pulmonary valve dysplasia who underwent transvalvular annular patch (TAP) procedure (control group) or an individualized pulmonary valve bi-orifice procedure (observation group) were studied. The RVOT for each patient in the observation group was individually reconstructed per the patient's weight and the size of the autologous pulmonary valve using the bi-orifice method; however, increasing the cross-sectional area of the pulmonary valve annulus without destroying its integrity. The result was then compared to the control group, where TAP procedures were applied to evaluate the short to mid-term outcome(s). An in vitro simulation test was used to verify the anti-regurgitation mechanism of the new method.

Results: The in vitro simulation test indicated that the anti-regurgitation mechanism was completed by the pericardial patch and the autologous pulmonary valve movement toward each other. Thus, for clinical applications, patients in both groups were compared. The results showed no significant differences in cardiopulmonary bypass and aortic cross-clamp time, mechanical ventilation, and ICU and post-operative residence between the two groups.

During the follow-up period (3- to 12-years), 14 patients in the observation group had mild regurgitation after surgery (22.2%), while 10 patients had moderate pulmonary regurgitation (15.8%) with no right ventricular (RV) dilation. On the other hand, 22 patients (39.6%) had moderate to severe regurgitation in the control group, while left pulmonary artery stenosis occurred in one patient. In the control group, six patients (9.2%) with severe RV dilation were reoperated.

Conclusion: Individualized pulmonary valve bi-orifice procedure is a safe and excellent method for reconstructing RVOT in ToF.

Early experience with surgical strategies aimed at preserving the pulmonary valve and annulus during repair of tetralogy of Fallot

Background :

During repair of tetralogy of fallot (TOF) we modified surgical strategies to preserve the valve and annulus if the pulmonary valve leaflets are pliable and not significantly dysplastic.

Methods :

Initially, the repair was done from the main pulmonary artery (Group-1, 215 patients) and later through an additional incision in the infundibulum of the right ventricle (Group-2, 73 patients). Recently, we changed the approach to commissurotomy of the fused leaflets by releasing the supra valvar tethering and delamination of the cuspal apparatus till the base to improve the mobility of the cusps and do a controlled commissurotomy (Group-3, 14 patients). With delamination, we could extend the limit of the repair to a z-score of –3.5.

Results :

There was no hospital mortality; two patients died at home after discharge. A mean follow-up of 42.01 months ± 19.25 is available for 198 patients (92%) for group 1, 16.03 ± 7.45 for group 2, and 4.07 ± 2.09 for group 3. The re-intervention-free survival is 94.4% in group 1. The z value improved from -3 (-3–-2) to -1.2 (-3 – 0), P = 0.001 in Group 1, from -2.8 (-3–-2.4) to -1 (-1.1–-0.7), P = 0.001 in Group 2 and from –3 (-4–-3) to -1, P = 0.001 in Group 3. In all the groups, there was trivial or mild pulmonary regurgitation.

Conclusions :

During repair of TOF, adequate valve/annulus sparing is possible if the repair is done from both the main pulmonary artery and infundibular incisions using the delamination technique.

Tetralogy of Fallot: T-shaped infundibulotomy for pulmonary valve-sparing procedure

This new and easily reproducible pulmonary valve-sparing technique for the correction of Tetralogy of Fallot is based on a conservative management of the native pulmonary valve to preserve its growth potential. From July 2015 to December 2019, 67 children presenting with a Tetralogy of Fallot were operated consecutively in a single centre using this technique in all cases. A T-shaped infundibulotomy is used to release the anterior pulmonary annulus from any muscular attachment. After myocardial resection and ventricular septal defect closure, an extensive commissurotomy is achieved. Finally, the right ventricular outflow tract remodelling is completed by a shield-shaped bovine patch with an oversized square superior edge, attached directly on the pulmonary valve annulus, with an effect of systolic traction. Sixty patients (89.5%) had a Tetralogy of Fallot repair with preservation of the pulmonary valve. To date, with a median follow-up of 38.2 [14–64] months, no patient has needed a surgical or interventional procedure for pulmonary valve stenosis or regurgitation, with low residual gradients. This procedure could provide a significant increase in native pulmonary valve preservation. Long-term studies are needed to assess pulmonary valve growth and the consequent reduction in surgical or interventional reoperations.

Association of Pulmonary Valve Morphology Differences With Outcomes in Tetralogy of Fallot Repair With Right Ventricular Outflow Tract Incision

Background: Current observational studies may not have large samples to investigate the relationship between pulmonary valve (PV) morphology differences and outcomes after complete repair for tetralogy of Fallot (TOF) by right ventricular outflow tract (RVOT) incision. This study aimed to assess the impact of PV morphology differences on outcomes after complete repair for TOF. Methods: This is a retrospective cohort study. Consecutive patients who underwent TOF repair with RVOT incision at Fuwai Hospital from January 2012 to December 2017 were included and compared according to PV morphology differences (unicuspid or bicuspid was abnormal morphology, while the tricuspid valve was normal morphology). The primary outcome was defined as a composite of death, or reintervention, or significant annular peak gradient (APG), or significant pulmonary regurgitation (PR), whichever occurred first. Multivariable Cox model analysis was used to assess the relationships between PV morphology differences and outcomes. Subgroup analysis and Propensity-score analysis were performed as sensitivity analyses to assess the robustness of our results. Results: The cohort included a total of 1,861 patients with primary diagnosis of TOF, with 1,688 undergoing CR-TOF with RVOT incision. The median age was 318 days [interquartile range (IQR): 223-534 days], a median weight of 8.9 kg (IQR: 7.6-10.5 kg) and 60.0% (1,011) were male. Complete follow-up data were available for 1,673 CR-TOF patients with a median follow-up duration of 49 months. Adjusted risks for the primary outcome and significant APG were lower for patients with normal PV morphology at follow up [adjusted hazard ratio (HR): 0.68; 95% CI: 0.46-0.98; adjusted HR: 0.22; 95% CI: 0.07-0.71, respectively]. The trend for the primary outcome during follow-up remained unchanged, even in subgroups and propensity score matching analyses. Conclusions: In this analysis of data from a large TOF cohort, patients with normal tricuspid PVs were associated with a decreased risk of the primary outcome and a lower risk of significant APG, as compared with patients with abnormal unicuspid or bicuspid PVs.

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.

Palliative Balloon Pulmonary Valvotomy in Tetralogy of Fallot: Is There a Role in 2021?

The current treatment practice for Tetralogy of Fallot (TOF) is to undertake complete surgical repair between 6–9 months of age with excellent immediate and long-term results. In patients with increased cyanosis or frequent cyanotic spells, younger age of complete repair as early as 3 months is usually acceptable. Although neonatal TOF repair is reported with good immediate survival from a few centres, post-operative morbidity is significant, and the hospital stay is prolonged. Hence, in neonates and small term and preterm infants with severe cyanosis, palliative procedures such as modified Blalock-Taussig (BT) shunt, ductal stenting, right ventricular outflow tract (RVOT) stenting and balloon pulmonary valvotomy (BPV) have been reported. With the development of low-profile stents, an increasing clinician experience and more predictable outcome with both duct and RVOT stenting, these procedures have gained popularity as the preferred palliations for TOF at most centres. We reviewed the literature to analyse whether BPV for TOF palliation, a technique first reported three decades ago, still has a role in the present era of paediatric cardiac care. In this review, we have concluded that BPV has very specific indications in patients with TOF, with predominantly valvar pulmonary stenosis, and may be a preferred option over other palliative strategies in hypoxemic preterm or low-birth weight infants.

Pulmonary Valve-Sparing Techniques for Tetralogy of Fallot: A Systematic Approach for Maximizing Success and Minimizing Risk

Valve-sparing techniques for the treatment of Tetralogy of Fallot with pulmonary stenosis have evolved over the past few decades. This article will discuss the rationale for a more aggressive approach to sparing the pulmonary valve, the various techniques available (including commissurotomy, leaflet thinning and debridement, balloon dilation, and finally modified monocusp repair), as well as a systematic approach for employing these techniques based on individual patient anatomy in a manner that takes full advantages of the benefits of the valve-sparing approach while mitigating the risks involved.

Evolving Techniques for the Achievement of Optimal Long-Term Results After Tetralogy of Fallot Repair

Several techniques designed to improve long-term results after repair of tetralogy of Fallot are described. We have recently embarked on a program focused on preserving the native pulmonary valve. Here, combined techniques are described in detail, including intraoperative pulmonary valve balloon dilatation, pulmonary valve reconstruction by delamination and resuspension of the leaflets, and pulmonary valve annulus augmentation. As with any other complex congenital heart disease, senior surgeons should select teaching cases, starting from the less severe side of the spectrum.

Autopsy in adults with congenital heart disease (ACHD)

The adult congenital heart diseases (ACHD) population is exceeding the pediatric congenital heart diseases (CHD) population and is progressively expanding each year, representing more than 90% of patients with CHD. Of these, about 75% have undergone surgical and/or percutaneous intervention for palliation or correction. Autopsy can be a very challenging procedure in ACHD patients. The approach and protocol to be used may vary depending on whether the pathologists are facing native disease without surgical or percutaneous interventions, but with various degrees of cardiac remodeling, or previously palliated or corrected CHD. Moreover, interventions for the same condition have evolved over the last decades, as has perioperative myocardial preservations and postoperative care, with different long-term sequelae depending on the era in which patients were operated on. Careful clinicopathological correlation is, thus, required to assist the pathologist in performing the autopsy and reaching a diagnosis regarding the cause of death. Due to the heterogeneity of the structural abnormalities, and the wide variety of surgical and interventional procedures, there are no standard methods for dissecting the heart at autopsy. In this paper, we describe the most common types of CHDs that a pathologist could encounter at autopsy, including the various types of surgical and percutaneous procedures and major pathological manifestations. We also propose a practical systematic approach to the autopsy of ACHD patients.

Predicting the Future: Tetralogy of Fallot Will Be Primarily Treated with Catheter Based Intervention Within Two Decades. Surgeon's Perspective

Interventional cardiology has made extraordinary advances over recent years, but most are still limited to addressing single intracardiac or valvular lesions. This debate considers whether complete interventional repair of more complex congenital defects might become achievable. Tetralogy of Fallot (ToF) is probably the first candidate where complete interventional repair might be achieved-given that various components of the defect have already been successfully addressed-albeit as either a palliative intervention (RVOT stenting) or to address the sequelae of standard surgery (percutaneous PVR). This article considers the challenges that would need to be overcome in terms of the morphology of the condition, the age limitations, and the necessary technological advancements that would be required-while setting these against the benchmark of current surgical outcomes and the parallel progress that is being developed in surgical correction. While complete interventional repair of ToF may still be beyond current techniques, a hybrid approach between surgeons and intentional cardiologists can strive to create a life-long paradigm of care that minimizes the need for surgery and focuses on the maintenance of a healthy right ventricle, such that patients born with ToF can achieve normal life expectancy.

Valve-sparing repair with skeletonization of the pulmonary annulus for tetralogy of Fallot

Pulmonary valve preservation in tetralogy of Fallot (TOF) repair is one of the most challenging issues. Herein, we describe a novel valve-sparing technique for TOF repair that primarily consists of skeletonization of the anterior part of the pulmonary annulus and gentle dilatation by preserving the pulmonary valve and annulus integrity. With encouraging early results, this technique is suggested to prevent severe pulmonary regurgitation and provide acceptable relief of pulmonary stenosis in patients with TOF.

Validity of Pulmonary Valve Z-Scores in Predicting Valve-Sparing Tetralogy Repairs-Systematic Review †

There is a lack of consensus regarding the preoperative pulmonary valve (PV) Z-score “cut-off” in tetralogy of Fallot (ToF) patients to attempt a successful valve sparing surgery (VSS). Therefore, the aim of this study was to review the available evidence regarding the association between preoperative PV Z-score and rate of re-intervention for residual right ventricular outflow tract (RVOT) obstruction, i.e. successful valve sparing surgery. A systematic search of studies reporting outcomes of VSS for ToF was performed utilizing PubMed, EMBASE, and Scopus databases. Patients with ToF variants such as pulmonary atresia, major aortopulmonary collaterals, absent pulmonary valve, associated atrioventricular septal defect, and discontinuous pulmonary arteries were excluded. Out of 712 screened publications, 15 studies met inclusion criteria. A total of 1091 patients had surgery at a median age and weight of 6.9 months and 7.2 kg, respectively. VSS was performed on the basis of intraoperative PV assessment in 14 out of 15 studies. The median preoperative PV Z-score was −1.7 (0 to −4.9) with a median re-intervention rate of 4.7% (0–36.8%) during a median follow-up of 2.83 years (1.4–15.8 years). Quantitatively, there was no correlation between decreasing preoperative PV Z-scores and increasing RVOT re-intervention rates with a correlation coefficient of −0.03 and an associated p-value of 0.91. In observational studies, VSS for ToF repair was based on intraoperative evaluation and sizing of the PV following complete relief of all levels of obstruction of the RVOT, rather than pre-operative echocardiography derived PV Z-scores.

Bidirectional Glenn for residual outflow obstruction in Tetralogy of Fallot

BACKGROUND

Residual right ventricular outflow obstruction during Tetralogy of Fallot repair necessitates peri-operative revision often requiring trans-annular patch with its negative sequels. Bidirectional Glenn shunt in this setting reduces trans-pulmonary gradient to avoid revision.

METHODS

Bidirectional Glenn shunt was added during Tetralogy repair in patients with significant residual obstruction. A total of 53 patients between January, 2011 and June, 2018 were included. Final follow-up was conducted in July, 2018.

RESULTS

Mean age at operation was 5.63±3.1 years. Right to left ventricular pressure ratio reduced significantly (0.91±0.09 versus 0.68±0.05; p&lt;0.001) after bidirectional Glenn, avoiding revision in all cases. Glenn pressures at ICU admission decreased significantly by the time of ICU discharge (16.7±3.02 versus 13.5±2.19; p&lt;0.001). Pleural drainage ≥ 7 days was seen in 14 (26.4%) patients. No side effects related to bidirectional Glenn-like facial swelling or veno-venous collaterals were noted. Mortality was 3.7%. Discharge echocardiography showed a mean trans-pulmonary gradient of 32.11±5.62 mmHg that decreased significantly to 25.64±5 (p&lt;0.001) at the time of follow-up. Pulmonary insufficiency was none to mild in 45 (88.2%) and moderate in 6 (11.8%). Mean follow-up was 36.12±25.15 months (range 0.5-90). There was no interim intervention or death. At follow-up, all the patients were in NYHA functional class 1 with no increase in severity of pulmonary insufficiency.

CONCLUSION

Supplementary bidirectional Glenn shunt significantly reduced residual right ventricular outflow obstruction during Tetralogy of Fallot repair avoiding revision with satisfactory early and mid-term results.

Tetralogy of Fallot in the Current Era

Only few studies have reported long-term outcome of the transatrial-transpulmonary approach in the current era of management of tetralogy of Fallot (ToF). We investigated 15-year outcome of correction via a transatrial-transpulmonary approach in a large cohort of successive patients operated in the 21st century. All infant ToF patients undergoing transatrial-transpulmonary ToF correction between 2000 and 2015 were included (N = 177, 106 male, median follow-up 7.1 (interquartile range 3.0-10.9) years. Data regarding postoperative complications, reinterventions, development of atrial and ventricular arrhythmia, cardiac function, and survival were evaluated. Prior shunting was performed in 10 patients (6%). The transatrial-transpulmonary approach resulted in valve-sparing surgery in 57 patients (32%). Postoperative surgical complications included junctional ectopic tachycardia (N = 12, 7%), pericardial (N = 10, 6%) or pleural effusion (N = 7, 3%), chylothorax (N = 7, 4%), bleeding requiring reoperation (N = 4, 3%), and superficial wound infection (N = 1). Fifty-one patients underwent 68 reinterventions, mainly due to pulmonary restenosis (PS) (N = 57). ToF correction at age <2 months and double outlet or double-chambered right ventricle variants of the ToF spectrum were independent predictors for reintervention. Patients undergoing valve-sparing ToF correction had a significant longer PR-free survival than those with a transannular patch (8.5 [95% confidence interval 6.8-10.3] years vs 1.1 [95% confidence interval 0.8-1.5] years; P < 0.001). Overall mortality was 2.8%; mortality rates were higher in premature/dysmature newborns (0.7% vs 9.5%; P < 0.001). Although the 15-year outcome of the transatrial-transpulmonary approach in terms of postoperative complications and mortality rates is excellent, the high incidence of moderate and severe PR is worrisome. Valve-sparing surgery was associated with a substantially lower incidence of PR, yet was surgically not possible in the majority of patients.