Tetralogy of Fallot: favorable outcome of nonneonatal transatrial, transpulmonary repair

Young infants with symptomatic tetralogy of Fallot: Shunt or primary repair?

Objectives

The optimal treatment strategy for symptomatic young infants with tetralogy of Fallot (TOF) is unclear. We sought to compare the outcomes of staged repair (SR) (shunt palliation followed by second-stage complete repair) versus primary repair (PR) at 2 institutions that have exclusively adopted each strategy.

Methods

We performed propensity score-matched comparison of 143 infants under 4 months of age who underwent shunt palliation at one institution between 1993 and 2021 with 122 infants who underwent PR between 2004 and 2018 at another institution. The primary outcome was mortality. Secondary outcomes were postoperative complications, durations of perioperative support and hospital stays, and reinterventions. Median follow-up was 8.3 years (interquartile range, 8.1-13.4 years).

Results

After the initial procedure, hospital mortality (shunt, 2.8% vs PR, 2.5%; P = .86) and 10-year survival (shunt, 95%; 95% confidence interval [CI], 90%-98% vs PR, 90%; 95% CI, 81%-95%; P = .65) were similar. The SR group had a greater risk of early reinterventions but similar rates of late reinterventions. Propensity score matching yielded 57 well-balanced pairs. In the matched cohort, the SR group had similar freedom from reintervention (55%; 95% CI, 39%-68% vs 59%; 95% CI, 43%-71%; P = .85) and greater survival (98%; 95% CI, 88%-99.8% vs 85%; 95% CI, 69%-93%; P = .02) at 10 years, as the result of more noncardiac-related mortalities in the PR group.

Conclusions

In symptomatic young infants with TOF operated at 2 institutions with exclusive treatment protocols, the SR strategy was associated with similar cardiac-related mortality and reinterventions as the PR strategy at medium-term follow-up.

Effectiveness of pulmonary valve-sparing strategy for transatrial-transpulmonary repair of tetralogy of Fallot: a single institution experience

OBJECTIVE

We report the midterm results of our strategy utilizing transatrial-transpulmonary repair for tetralogy of Fallot at a single institution in a low-middle income country.

METHODS

Medical records were retrospectively reviewed for 532 consecutive patients who underwent definitive repair of tetralogy of Fallot at our institution from 2010 to 2020.

RESULTS

The median age and weight of patients in the study patients were 11.6 months (interquartile range, 8.6-17.2 months) and 7.5 kg (interquartile range, 6.8-8.8 kg). The pulmonary valve annulus was preserved (no transannular patch) in 398 patients (75%) and a mini-transannular patch was utilized for 134 patients (25%). The overall survival was 98% at 1 year, and 97% at 10-years follow-up, respectively. Longer postoperative ventilation time was the only risk factor correlated to early death (p = 0.004; Odds Risk, 1.04; 95% confidence intervals, 1.01-1.07). Fourteen patients required pulmonary valve replacement (2.6%, 14/532), four required surgical resection to relieve right ventricular outflow tract obstruction (0.8%, 4/532), and freedom from reoperation of the right ventricular outflow tract was 87% at 10 years. The only risk factor for right ventricular outflow tract reoperation was a postoperative systolic pressure gradient through the right ventricular outflow tract of greater than 50 mmHg (p < 0.001; HR, 47; 95% confidence intervals, 9.1-244). In total, 94.6% (471/489) of the patients were asymptomatic at the latest follow-up without significant arrhythmia.

CONCLUSION

At our institution in an low-middle income country, the transatrial-transpulmonary repair for tetralogy of Fallot has excellent midterm results with few reoperations required. Close long-term follow-up is essential for patients who undergo repair with a mini-transannular patch and may eventually require pulmonary valve replacement.

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.

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.

Patch Enlargement May Not Be a Good Strategy for Tetralogy of Fallot with Unbalanced Pulmonary Artery Branches

OBJECTIVES

To figure out the optimal strategy to manage Tetralogy of Fallot (TOF) with unbalanced pulmonary artery(PA) branches by investigating the different effects of PA plasty on the development of the hypoplastic PA (HPA).

METHODS

A single center, retrospective analysis was carried out to compare the outcome of different PA plasty methods on the development of HPA in patients of TOF with unbalanced PA branches. Size and balance of the PA branches were used to evaluate the outcome of PA plasty.

RESULTS

In the NATIVE group, 100% of the HPAs were well-developed and all the PA branches became balanced, while in the PATCH and EXTENSION groups, the percentage of well-developed HPAs was 40% and 33%, respectively, and none of the PA branches were balanced. In addition, HPAs became atretic in 28% of the patients in the patch enlargement group.

CONCLUSIONS

For TOF with unbalanced PA branches, patch enlargement may not be a good treatment strategy, as it reduces the growth potential of HPA and even causes iatrogenic atresia. Leaving the HPA in the native state without patch enlargement may be a good strategy.

Long-term Outcomes of Transatrial-Transpulmonary Repair of Tetralogy of Fallot With Anomalous Coronary Arteries

Repair of tetralogy of Fallot (TOF) can be complicated by the presence of an anomalous coronary artery (ACA) crossing the right ventricular outflow tract (RVOT). This study sought to evaluate the late outcomes of a policy of transatrial-transpulmonary repair for this condition. The transatrial-transpulmonary approach was used in 864 consecutive TOF repairs between 1993 and 2018 at a single institution, of which 55 (6%) patients had an ACA. Nineteen (35%,19/55) patients underwent prior palliation. Late survival and freedom from reoperations were compared with the general cohort of 809 patients who underwent complete repair during the same period. Early mortality was 2% (1/55). Median follow-up was 15.6 years. Late mortality was 6% (3/54). Absence of a preoperative diagnosis of ACA was not a risk factor for worse outcomes in terms of late re-interventions, acute coronary syndrome, residual RVOT gradient, and late mortality. Survival was 91% (95% confidence interval [CI]: 77-96%) at 20 years and was comparable to the general TOF cohort (95%, 95% CI: 90-98%, P = 0.12). Actuarial freedom from any re-intervention was 46% (95% CI: 27-62%) at 20 years, which was also comparable to the general cohort (31%, 95% CI: 20-42%, P = 0.19). The presence of an ACA does not appear to affect late survival or re-intervention rates in patients undergoing transatrial-transpulmonary repair of TOF.

Implantation of monocusp valve prolongs the duration of chest tube drainage in children with tetralogy of fallot after corrective surgery

BACKGROUND

Right ventricular outflow tract obstruction relief is one of the major procedures during the total correction of tetralogy of Fallot (TOF). Pulmonary insufficiency (PI) is usually inevitable after a transannular incision with a patch repair is performed. Therefore, some surgeons advocate to place a monocusp valve within the transannular patch (TAP) in order to decrease the severity of the PI. However, the monocusp valve seemed not be very effective in some patients who underwent the complete TOF repair.

METHODS

Patients who had the classic form of TOF between January 2009 and January 2017 and underwent the corrective surgery with a TAP by the same cardiovascular surgeon were identified for further analysis. Clinical information including demographics at operation, perioperative data, and postoperative outcome were collected retrospectively and compared between the group with and without a monocusp valve.

RESULTS

A total of 24 TOF cases were included in the final analysis, and 16 (66.7%) patients received a monocusp valve placement. The patients' characteristics before and during the surgery were similar between the two groups. The median duration of chest tube drainage after the total correction in the monocusp group was longer than those without the valve (p = 0.04). There was no difference in the immediate postoperative data, including the inflammation/infection status, the duration of mechanical ventilation, and the length of ICU and hospital stay.

CONCLUSION

Implantation of a monocusp valve during the total TOF correction using a TAP did not bring benefit to improve the immediate postoperative outcomes, especially the duration of the pleural drainage. Further study with a prospective design and a larger number of cases is needed.

The role of primary surgical repair technique on late outcomes of Tetralogy of Fallot: a multicentre study

OBJECTIVES

Repair of Tetralogy of Fallot (TOF) has currently excellent results with either transventricular or transatrial approach. However, it is unclear as to which has better late outcomes and what role of residual pulmonary valve (PV) regurgitation in the long term is. We report on late clinical outcomes after repair in a large series of patients with TOF, focusing on the type of surgical technique.

METHODS

This analysis is a retrospective multicentre study on patients undergoing TOF repair in infancy. The exclusion criteria of the study were TOF with pulmonary atresia or absent PV.

RESULTS

We selected 720 patients who had undergone TOF repair (median age 5.7 months, interquartile range 3.7-11.7). Preoperative cyanotic spells occurred in 18%. A transatrial repair was performed in 433 (60.1%) patients. The PV was preserved in 249 (35%) patients, while the right ventricular outflow tract was reconstructed with a transannular patch (60.4%) or a conduit (4.6%) in the rest of the patients. At a median follow-up of 4 years (range 1-21, 86% complete), 10 (1.6%) patients died, while 39 (6.3%) patients required surgical reoperation and 72 (11.7%) patients required an interventional procedure. The propensity match analysis showed that the incidence of postoperative complications and adverse events at follow-up were significantly increased in patients undergoing transventricular approach repair with transannular patch (P = 0.006) and PV preservation was a significant protective factor against postoperative complications (P = 0.009, odds ratio 0.5) and late adverse events (P = 0.022).

CONCLUSIONS

Surgical repair of TOF in infancy is a safe procedure, with good late clinical outcomes. However, transatrial approach and PV preservation at repair are associated with lower early and late morbidity.

Preventing Arrhythmic Death in Patients With Tetralogy of Fallot: JACC Review Topic of the Week

Patients with tetralogy of Fallot are at risk for ventricular arrhythmias and sudden cardiac death. These abnormalities are associated with pulmonary regurgitation, right ventricular enlargement, and a substrate of discrete, slowly-conducting isthmuses. Although these arrhythmic events are rare, their prediction is challenging. This review will address contemporary risk assessment and prevention strategies. Numerous variables have been proposed to predict who would benefit from an implantable cardioverter-defibrillator. Current risk stratification models combine independently associated factors into risk scores. Cardiac magnetic resonance imaging, QRS fragmentation assessment, and electrophysiology testing in selected patients may refine some of these models. Interaction between right and left ventricular function is emerging as a critical factor in our understanding of disease progression and risk assessment. Multicenter studies evaluating risk factors and risk mitigating strategies such as pulmonary valve replacement, ablative strategies, and use of implantable cardiac-defibrillators are needed moving forward.

Tetralogy of Fallot with coronary crossing the right ventricular outflow tract: A tale of a bridge and the artery

A coronary artery crossing the right ventricular outflow tract is a subset of a larger pathomorphological cohort known as an anomalous coronary artery (ACA) in the tetralogy of Fallot (TOF). The best possible outcome in a patient with TOF and ACA is decided by judicious selection of optimum preoperative investigative information, the timing of surgery, astute assessment of preoperative surgical findings, and appropriate surgical technique from a wide array of choices. In most instances, the choice of surgical technique is determined by the size of the pulmonary annulus and the anatomical relation of ACA to the pulmonary annulus. In the present era, complete, accurate preoperative diagnosis and primary repair is a routine procedure with strategies to avoid a right ventricle-to-pulmonary artery conduit.

Pulmonary regurgitation after repaired tetralogy of Fallot: surgical versus percutaneous treatment

Pulmonary regurgitation is the most important sequellae after correction of Tetralogy of Fallot and has a considerable impact over the right ventricle. Surgery has demonstrated low early mortality after pulmonary valve replacement and good long-term outcomes, remaining nowadays the gold standard treatment of pulmonary regurgitation in rTOF patients. Nevertheless, transcatheter pulmonary valve implantation has emerged as a new, safe and efficient alternative to surgical valve replacement. In this review article, we try to evaluate and compare both techniques to find out which is the best therapeutic option in this patients.

Multi-detector computed tomography in the assessment of tetralogy of Fallot patients: is it a must?

Background

Tetralogy of Fallot (TOF) accounts for 10% of all CHD. It classically consists of ventricular septal defect (VSD), aortic overriding, right ventricular outflow tract (RVOT) obstruction, and RV hypertrophy. There are many anatomic variants, associated intracardiac and extracardiac anomalies that must be taken into consideration when imaging and planning the surgical procedure needed. Multi-detector computed tomography (MDCT), with its high spatial and temporal resolution, has a pivotal role in the evaluation of complex anatomical findings in both unrepaired and repaired TOF patients.

Main body

Though MDCT has a limited role in the initial diagnosis of TOF, it is particularly important when there is a question about anatomy of pulmonary arteries (PAs) (whether sizable, hypoplastic, or atretic), presence of major aorto-pulmonary collaterals (MAPCAs) and presence of additional VSDs. Additionally, MDCT is crucial in the diagnosis of different anatomical variants of TOF. TOF patients with absent pulmonary valve classically have hugely dilated PAs which raise an important question about the degree and severity of airways compression. This question can be accurately answered by MDCT. TOF with double-outlet RV (DORV) has variable degrees of aortic override which can be assessed by MDCT. An atrio-ventricular septal defect (AVSD) is seen in about 13% of TOF cases and typically occurs in patients with Down syndrome. MDCT can assess the size and extent of inlet VSD and size of both ventricles (balanced or unbalanced AVSD). Coronary artery anomalies are common and important association. MDCT can identify the presence of a major coronary artery crossing the RVOT, a left anterior descending (LAD) from RCA, or a dual LAD. The clinical importance of these anomalies is its susceptibility to injury during ventriculotomy incision required for TOF repair necessitating changing the usual approach of surgery.

Patients with reduced pulmonary blood flow undergo a systemic to pulmonary shunt. MDCT can assess the patency of the shunt, stenotic, or occluded segments. In surgically repaired TOF patients, MDCT can identify the sequalae and long-term complications including residual RVOT obstruction, conduit stenosis, RVOT patch aneurysm, RVH, and aortic root dilatation.

Conclusion

MDCT is a safe and reliable imaging modality that provides accurate assessment of anatomical variants and associated anomalies of TOF.

Surgical Options for Pulmonary Atresia with Ventricular Septal Defect in Neonates and Young Infants

BACKGROUND

The optimal surgical strategy for pulmonary atresia with ventricular septal defect (PA/VSD) in neonates and young infants is controversial. Staged repair may be associated with a higher risk of inter-stage mortality, while primary repair may lead to frequent post-repair re-interventions.

METHODS

From 2004 to 2017, 65 patients with PA/VSD who underwent surgical intervention before 90 days of age were identified and enrolled in this retrospective study. The cohort was divided into two groups: group-SR, who underwent initial palliation with staged repair (n = 50), and group-PR who underwent primary repair (n = 15).

RESULTS

There were three post-palliation in-hospital mortalities, four inter-stage mortalities, and one post-repair in-hospital mortality in group-SR. In group-PR, there was one in-hospital death and one late death. Five-year survival rates were comparable between the two groups (group-SR: 83.6%; group-PR: 86.7%; p = 0.754). During the median follow-up duration of 44.7 months (Inter-quartile range, 19-109 months), 40 post-repair re-interventions (22 in group-SR, 18 in group-PR) were performed in 26 patients (18 in group-SR, 8 in group-PR). On Cox proportional hazards model, primary repair was identified as the only risk factor for decreased time to death/1st post-repair re-intervention (Hazard ratio (HR): 2.3, p = 0.049) and death/2nd post-repair re-intervention (HR 2.91, p = 0.033).

CONCLUSIONS

A staged repair strategy, compared with primary repair, was associated with comparable overall survival with less frequent re-interventions after repair in young infants with PA/VSD. Lowering the inter-stage mortality after initial palliation by vigilant outpatient care and aggressive home monitoring may be the key to better surgical outcomes in this subset. Surgical outcomes of PA with VSD according to the surgical strategies. Patient 1 (birth weight: 2.7 kg) underwent primary Rastelli-type repair at post-natal day # 50 (body weight: 3.8 kg) using Contegra® 12 mm. The postoperative course was rocky, with long ventilatory support (10 days), ICU stay (14 days), and hospital stay (20 days). Cardiac CT scan at 9 months post-repair showed severe branch pulmonary artery stenosis, which necessitated LPA stenting at 12 months post-repair and RV-PA conduit replacement with extensive pulmonary artery reconstruction at 25 months post-repair. Patient 2 (birth weight: 2.5 kg) underwent RMBT at post-natal day #30 (body weight: 3.4 kg) using 4 mm PTFE vascular graft and staged Rastelli-type repair at post-natal 11 months using a hand-made Gore-Tex valved conduit (14 mm). No post-repair re-intervention has been performed. Cardiac CT scan at 90 months post-repair showed no branch pulmonary artery stenosis.CT computed tomography, ICU intensive care unit, LPA left pulmonary artery, PA pulmonary atresia, PTFE polytetrafluoroethylene, RMBT right modified Blalock-Taussig shunt, RV-PA right ventricle to pulmonary artery, VSD ventricular septal defect.

Staged Versus Complete Repair in the Symptomatic Neonate With Tetralogy of Fallot

BACKGROUND

The optimal management of tetralogy of Fallot (TOF) in symptomatic neonates remains unknown. We compared outcomes for those undergoing palliation vs complete repair in the neonatal period.

METHODS

In a retrospective cohort study of symptomatic neonates with TOF who had a neonatal complete repair (group 1, n = 112) or staged repair (group 2, n = 26) from 2000 to 2013, we compared outcomes at 4 time points: neonatal complete repair vs palliation (group 1 vs 2A), neonatal vs later complete repair (group 1 vs 2B), the single vs combined admissions to achieve a complete repair (group 1 vs group 2A + 2B), and cumulative events 2 years after complete repair for both groups.

RESULTS

Demographics, anatomy, comorbidities, surgical approach, and mortality were similar between groups 1 and 2. Group 1 had a longer duration of cardiopulmonary bypass and deep hypothermic circulatory arrest and more postprocedure cardiac events compared with group 2A; a longer duration of intubation, intensive care, and postprocedure hospital stay compared with groups 2A and 2B; and a longer total hospital stay compared with group 2B. With combined admissions for group 2, there was no difference in the total duration of intensive care, total hospital stay, or reinterventions compared with group 1.

CONCLUSIONS

Both management options result in similar survival; however, early morbidity was greater with neonatal complete repair. The impact of increased neonatal exposures, such as cardiopulmonary bypass, deep hypothermic circulatory arrest, and intensive care, on neurocognitive development requires further study but should be considered when choosing an optimal strategy.

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.

Right Heart-Pulmonary Circulation Unit in Congenital Heart Diseases

The right ventricle plays a major role in congenital heart disease. This article describes the right ventricular mechanics in some selected congenital heart diseases affecting the right ventricle in different ways: tetralogy of Fallot, Ebstein anomaly, and the systemic right ventricle.

Impact of Percutaneous Pulmonary Valve Implantation on the Timing of Reintervention for Right Ventricular Outflow Tract Dysfunction

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart defect. Early surgical repair has dramatically improved the outcome of this condition. However, despite the success of contemporary approaches with early complete repair, these are far from being curative and late complications are frequent. The most common complication is right ventricle outflow tract (RVOT) dysfunction, affecting most patients in the form of pulmonary regurgitation, pulmonary stenosis, or both, and can lead to development of symptoms of exercise intolerance, arrhythmias, and sudden cardiac death. Optimal timing of restoration of RVOT functionality in asymptomatic patients with RVOT dysfunction after TOF repair is still a matter of debate. Percutaneous pulmonary valve implantation, introduced almost 2 decades ago, has become a major game-changer in the treatment of RVOT dysfunction. In this article we review the pathophysiology, the current indications, and treatment options for RVOT dysfunction in patients after TOF repair with a focus on the role of percutaneous pulmonary valve implantation in the therapeutic approach to these patients.

Investigation of associated factors with post-operative outcomes in patients undergoing Tetralogy of Fallot correction

Background

Tetralogy of Fallot (TOF) is one of the congenital cardiac abnormality which occurs during embryonic time. Although surgical correction, especially early operation, is the best way to treat patients, still contributing factors in morbidity and mortality is controversial. The objective of this study is to investigate potential factors which might be correlated with post-operative outcomes of TOF.

Methods

In this retrospective study, 349 monitored patients with TOF correction were selected. Median of age was 4 (0.66–8) year, 58% of patients were male and 42% were female. Time of inotropic drug, extubation time, and ICU stay were considered as post-operative outcomes which extension of each of them increased the risk of death.

Results

Ventricular septal defect enlargement was associated with longer extubation time and ICU stay. Higher ratio of pre-operative haematocrit was correlated with mortality (0.047).

Conclusions

Results of this study demonstrated that haematocrit ratio before operation should be considered as a predictive factor, and patients with higher ratio of haematocrit require more care after operation. VSD enlargement is associated with longer extubation time and ICU stay.

Impact of surgery on presence and dimensions of anatomical isthmuses in tetralogy of Fallot

Objective

In tetralogy of Fallot (TOF), the dominant ventricular tachycardia substrates are slow-conducting anatomical isthmuses. Surgical correction has evolved, which might have influenced isthmus presence and dimensions.

Methods

One hundred and forty-two postmortem TOF specimens (84/58 corrected/uncorrected) were studied for isthmus presence. Isthmus 1 is located between the tricuspid annulus and right ventricular (RV) outflow tract (RVOT) patch/RV incision, isthmus 2 between RVOT patch/RV incision and pulmonary valve, isthmus 3 between pulmonary valve and ventricular septal defect (patch), isthmus 4 between ventricular septal defect (patch) and tricuspid annulus. Isthmus width and thickness were measured.

Results

Of 84 corrected postmortem TOF specimens (death: 6.6 years (4.0–11.5)), 83 demonstrated isthmus 1 (99%, width=25±10 mm, thickness=5±2 mm), 35 isthmus 2 (42%, width=10±9 mm, thickness=3±2 mm), 83 isthmus 3 (99%, width=10±6 mm, thickness=5±2 mm), and 5 isthmus 4 (6%, width=4±2 mm, thickness=2±1 mm). Transatrial-transpulmonary correction (n=49) as compared with transventricular correction (n=35) prevented isthmus 2 (0% vs 100%, P<0.001). Transatrial-transpulmonary correction at age <1 year (n=7) as compared with ≥1 year (n=42) required a smaller transannular RVOT patch (28±15 vs 45±14 mm, P<0.001). Mode and timing of correction did not influence presence and dimensions of isthmus 3. In corrected and uncorrected TOF specimens (death 1.8 years (0.5–6.6)), the range of isthmus 3 dimensions was broad (width: min=2 mm, max=32 mm; thickness: min=1, max 13 mm) across all ages. Isthmus 3 width and thickness were strongly correlated (r=0.65, P<0.001).

Conclusions

In TOF, the current routine use of transatrial-transpulmonary correction prevents isthmus 2. Correction <1 year reduces transannular patch size, which may influence isthmus 1 width later in life. Mode and timing of correction did not change prevalence and dimensions of isthmus 3, in which dimensions varied widely in uncorrected and corrected TOF.

Tetralogy Surgery - Back To Baltimore 70 Years Later: Melbourne Heritage and Group Tribute to Juan Comas

Surgery for Tetralogy of Fallot progressed rapidly from the palliative arterio-pulmonary Blalock-Taussig shunt, introduced in Baltimore 70 years ago, to the "classic" complete transventricular repair technique, with which excellent early results were achieved soon thereafter. However, as duration of follow-up increased, so did the awareness of development of troubling late complications, including severe pulmonary insufficiency, right ventricular dilatation and dysfunction, and tricuspid valve insufficiency, all contributing to increasing incidence of late reoperations, as well as to arrhythmias and sudden death. This realization fueled the initial introduction of the transatrial-transpulmonary repair technique by Kawashima, as well as the subsequent firm establishment of this technique within the framework of an integrated surgical approach by Roger Mee in Melbourne. In turn, Mee's numerous trainees and associates led the dissemination of this approach and provided the impetus for the current wide adoption of a variety of right ventricular and pulmonary valve preservation techniques. In addition to the outstanding surgical results reported by individual centers adopting this surgical strategy, encouraging multi-institutional data are emerging regarding the benefits of these approaches for more favorable early and, most importantly, late outcome. One student and strong proponent of the Melbourne approach was our late colleague and friend Juan Comas, to whose memory this article can serve as tribute.

Right Ventricular Dysfunction Due to Right Ventricular Outflow Tract Patch

Doppler tissue imaging analysis was used to examine the relationship between right ventricular function and right ventricular outflow tract damage in 54 patients with repaired tetralogy of Fallot. The patients were divided into three groups: 16 in whom the right ventricular outflow tract was directly sutured (group DS), 23 who had transventricular patch repair (group TVP), and 15 who had transannular patch repair (group TAP). The control group consisted of 16 age-matched patients who underwent patch closure of a ventricular septal defect (group C). The Tei index was obtained from tricuspid and pulmonary Doppler flow velocities. The right ventricular Tei index was significantly greater in groups TVP and TAP than in group DS. Doppler tissue imaging analysis in groups TVP and TAP showed shorter myocardial systolic velocity, diastolic peak velocity, and atrial diastolic peak velocity, lower peak myocardial velocity and acceleration during isovolumic contraction, and prolonged isovolumic relaxation and contraction times compared to groups DS and C. Right ventricular dysfunction is due to the right ventricular outflow tract patch. Thus, the right ventricular outflow tract may be essential for right ventricular ejection and maintenance of right ventricular function.

Technical performance score as predictor for post-discharge reintervention in valve-sparing tetralogy of Fallot repair

Recognition of late problems following repair of tetralogy of Fallot (TOF) with a transannular patch has stimulated modifications to preserve pulmonary valve (PV) function. This study assesses the ability of technical performance score (TPS) to determine the need for post-discharge reinterventions (RIs) in valve-sparing TOF repair. We retrospectively reviewed 157 patients following valve-sparing repair of TOF from 2007-2012. We assigned TPS as Class 1 (optimal), Class 2 (adequate), or Class 3 (inadequate) based on discharge echo and clinical criteria. Preoperative, discharge, and follow-up PV Z scores and post-discharge RIs were documented. Reasons for Class 2 or 3 designation were right ventricular outflow tract (RVOT) gradient in 52, pulmonary regurgitation in 13, residual ventricular septal defects in 7, both RVOT gradient and ventricular septal defects in 13, and both RVOT gradient and pulmonary regurgitation in 37 patients. Median follow-up was 19.6 (range: 0.1-86.1) months. Class 3 patients had a significantly longer median intensive care unit and hospital stay compared with Class 1 (3 vs 2 days [P = 0.015] and 7 vs 5 days [P < 0.001], respectively). Post-discharge RIs were significantly lower in Class 1 vs Class 2 and Class 3 (P = 0.003). Class 1 patients had significantly larger PV Z scores compared with Class 2 or Class 3 patients (P < 0.001). TPS is associated with post-discharge RI rate after valve-sparing TOF repair. Preoperative PV Z score is highly correlated with Class I TPS. Patient selection based on preoperative PV Z scores may help determine if valve-sparing approach is appropriate, thus minimizing the need for RIs.

Low incidence of arrhythmias in the right ventricular infundibulum sparing approach to tetralogy of Fallot repair

To improve outcomes, including arrhythmia incidence, for patients with tetralogy of Fallot (TOF), the authors' institution adopted an approach that minimizes or avoids transmural incision of the right ventricular outflow tract. When pulmonary blood flow is insufficient during the neonatal period, placement of an aortopulmonary artery shunt is preferred, followed by complete repair later in infancy. This study reviewed the perioperative and mid-term arrhythmia outcomes at the authors' institution using this approach. Patients who underwent TOF repair from 1995 to 2008 were included in the study. Patient demographics and surgical history were collected. The primary end points of the study included documented perioperative arrhythmias and arrhythmias at the 10-year follow-up assessment. Of the 298 patients who underwent TOF repair, 50 (17 %) had undergone prior placement of a systemic-to-pulmonary artery shunt. The median age at repair was 9.7 months (interquartile range, 6.3-16.2 months). Clinically significant perioperative arrhythmias were found in 12 patients (4 %) including 6 junctional tachycardias, 4 atrial tachycardias, and 1 temporary complete heart block. No patients were receiving antiarrhythmic medications more than 24 months after surgery. Of the 298 patients, 86 (29 %) had a follow-up period of 10 years or longer (median, 12.2 years). No patients experienced new arrhythmias, received antiarrhythmic therapy, experienced post-discharge ventricular tachycardia, had atrioventricular block, or required a pacemaker or defibrillator. The right ventricular infundibulum sparing approach is associated with an extremely low incidence of perioperative and midterm arrhythmias. The perioperative and mid-term outcomes compare favorably with existing data from programs favoring neonatal repair. Long-term follow-up evaluation is essential to determine whether this strategy can effectively alter late pathophysiology and minimize late-term arrhythmias and associated mortality.

Primary repair of symptomatic neonates with tetralogy of Fallot with or without pulmonary atresia

Recently, surgical outcomes of repair of tetralogy of Fallot (TOF) have improved. For patients with TOF older than 3 months, primary repair has been advocated regardless of symptoms. However, a surgical approach to symptomatic TOF in neonates or very young infants remains elusive. Traditionally, there have been two surgical options for these patients: primary repair versus an initial aortopulmonary shunt followed by repair. Early primary repair provides several advantages, including avoidance of shunt-related complications, early relief of hypoxia, promotion of normal lung development, avoidance of ventricular hypertrophy and fibrosis, and psychological comfort to the family. Because of advances in cardiopulmonary bypass techniques and accumulated experience in neonatal cardiac surgery, primary repair in neonates with TOF has been performed with excellent early outcomes (early mortality<5%), which may be superior to the outcomes of aortopulmonary shunting. A remaining question regarding surgical options is whether shunts can preserve the pulmonary valve annulus for TOF neonates with pulmonary stenosis. Symptomatic neonates and older infants have different anatomies of right ventricular outflow tract (RVOT) obstructions, which in neonates are nearly always caused by a hypoplastic pulmonary valve annulus instead of infundibular obstruction. Therefore, a shunt is less likely to preserve the pulmonary valve annulus than is primary repair. Primary repair of TOF can be performed safely in most symptomatic neonates. Patients who have had primary repair should be closely followed up to evaluate the RVOT pathology and right ventricular function.

Intersurgeon variability in long-term outcomes after transatrial repair of tetralogy of Fallot: 25 years' experience with 675 patients

OBJECTIVE

To compare the long-term reoperation rates among surgeons performing transatrial repair of tetralogy of Fallot.

METHODS

The data set of 675 patients undergoing transatrial repair of tetralogy of Fallot at 1 institution from 1980 to 2005 was analyzed for intersurgeon differences in the reoperation rates.

RESULTS

A follow-up period >15 years was available for 5 surgeons, allowing for comparison (541 patients; >80 patients/surgeon). The reintervention rate at 10 years varied from 8.8% (95% confidence interval [CI], 5.3%-14.5%) to 26.7% (95% CI, 14.9%-44.9%; hazard ratio, 3.4; P = .001). The procedures of 1 surgeon resulted in a reoperation rate of 10.5% at 20 years (95% CI, 5.4%-25.3%). The type of reoperation required varied among the surgeons. One surgeon had had no reoperations for pulmonary artery stenosis. Of the 5 surgeons, 2 (surgeons 2 and 5) had equivalent overall 10-year reoperation rates (24.1%, 95% CI, 12.9%-42.3%; vs 26.7%, 95% CI, 14.9%-44.9%; P = .32). Surgeon 5 had reoperation almost exclusively for right ventricular outflow tract obstruction (20.6%; 95% CI, 12.4%-33.1%) and surgeon 2 for right ventricular dilation (17.4%; 95% CI, 7.8%-36.3%). None of the patients treated by surgeon 5 required implantation of a valved conduit.

CONCLUSIONS

An analysis of the reoperation rate during the long-term follow-up of transatrial repair of tetralogy of Fallot identified variability in the outcomes among 5 surgeons. The analysis of these differences suggested that an optimal amount of opening of the right ventricular outflow tract can lead to a decreased reintervention rate. The analysis of intersurgeon variability in outcomes should be encouraged, because it will lead to improvements in cardiac surgery outcomes.

Native Pulmonary Valve Restoration After Remote Tetralogy of Fallot Repair

Methods to repair tetralogy of Fallot have evolved from large ventriculotomy, large transannular patch placement techniques to smaller, transatrial approaches with valve-sparing strategies in select patients. Despite these advances, there continue to be patients in whom transannular patch is inevitable, and the management of the resulting pulmonary insufficiency that develops from this has been the source of considerable discussion. Techniques aimed at restoring pulmonary valve competence utilizing the remaining valve leaflets after transannular patch placement have recently been proposed for very select patient populations. We review the technical aspects of the operation including removal of the transannular patch and bicuspidization of a formerly tricuspid pulmonary valve, which results in a competent, nonstenotic valve. This report confirms the feasibility of these operative details and highlights the importance of planning before initial repair of tetralogy of Fallot as a way to prepare for a future valve restoration procedure and therefore avoid prosthetic valve placement.

Early and late outcomes of total repair of tetralogy of Fallot: risk factors for late right ventricular dilatation

OBJECTIVES

This study was undertaken to assess the early and long-term results of total repair of tetralogy of Fallot (TOF) and to identify the risk factors associated with late right ventricular (RV) dilatation.

METHODS

The medical records of 326 patients (male:female = 192:134) who underwent total repair of TOF at Pusan National and Dong-A University Hospitals between July 1991 and May 2011 were retrospectively reviewed. Median age and weight at the time of operation were 13.0 months and 8.7 kg, respectively. Right ventricular end-diastolic dimensions and left ventricular end-diastolic dimensions were obtained during follow-up echocardiography to identify the risk factors associated with late RV dilatation.

RESULTS

There were one operative death (0.3%) and 8 late deaths (2.5%). Of late deaths, two were related to operation-related cardiac problems. Overall survival rates at 5, 10, and 15 years were 97.0%, 95.4%, and 95.4%, and the corresponding freedom from cardiac death were 98.8%, 98.8%, and 98.8%, respectively. Freedom from re-operation and re-intervention were 84.4%, 74.2% and 74.2%. Six patients underwent pulmonary valve replacement during the follow-up period. Transannular patch (P = 0.036) and postoperative ventilator support period (P < 0.001) were found to be significant risk factors of late RV dilatation in multivariate analysis.

CONCLUSIONS

Total correction of TOF can be performed with a very low mortality rate. However, the postoperative re-operation or re-intervention rates remain relatively high. Late RV dilatation after total repair of TOF was found to be associated with transannular patch enlargement and a longer postoperative ventilator support period.

Pulmonary stenosis and pulmonary regurgitation: both ends of the spectrum in residual hemodynamic impairment after tetralogy of Fallot repair

Repair of tetralogy of Fallot (TOF) has shown excellent outcomes. However it leaves varying degrees of residual hemodynamic impairment, with severe pulmonary stenosis (PS) and free pulmonary regurgitation (PR) at both ends of the spectrum. Since the 1980s, studies evaluating late outcomes after TOF repair revealed the adverse impacts of residual chronic PR on RV volume and function; thus, a turnaround of operational strategies has occurred from aggressive RV outflow tract (RVOT) reconstruction for complete relief of RVOT obstruction to conservative RVOT reconstruction for limiting PR. This transformation has raised the question of how much residual PS after conservative RVOT reconstruction is acceptable. Besides, as pulmonary valve replacement (PVR) increases in patients with RV deterioration from residual PR, there is concern regarding when it should be performed. Regarding residual PS, several studies revealed that PS in addition to PR was associated with less PR and a small RV volume. This suggests that PS combined with PR makes RV diastolic property to protect against dilatation through RV hypertrophy and supports conservative RVOT enlargement despite residual PS. Also, several studies have revealed the pre-PVR threshold of RV parameters for the normalization of RV volume and function after PVR, and based on these results, the indications for PVR have been revised. Although there is no established strategy, better understanding of RV mechanics, development of new surgical and interventional techniques, and evidence for the effect of PVR on RV reverse remodeling and its late outcome will aid us to optimize the management of TOF.

Tetralogy of Fallot

Management of the cyanotic neonate with tetralogy of Fallot (ToF) remains a challenging condition. Outcomes for single-stage repair of ToF have steadily improved over the past 30 years and the best results have been achieved with repair between 3 and 9 months of age. The traditional management of cyanotic neonates and small infants has been palliation with a Blalock–Taussig shunt, but this continues to carry a significant mortality that has remained relatively constant even in the contemporary series. This has led to the promotion of neonatal complete repair, but analysis of published outcomes would suggest that this also carries significant risk compared to repair at an older age. Low birth weight and small pulmonary arteries (PAs) remain the greatest independent risk factors. Right ventricular outflow tract (RVOT) stenting may offer an alternative approach to neonatal repair in high-risk neonates and allow for PA growth and delay of repair until the child reaches a safer age. A stratified approach to early management utilizing RVOT stenting in high-risk cases may lead to better overall outcomes.

Technical modification enabling pulmonary valve-sparing repair of a severely hypoplastic pulmonary annulus in patients with tetralogy of Fallot

OBJECTIVES

Although pulmonary valve-sparing repair is preferable for patients with tetralogy of Fallot, the repair of very small pulmonary valves is challenging. The present study evaluates our modification for preserving severely hypoplastic pulmonary valves in patients with tetralogy of Fallot.

METHODS

Sixty-eight consecutive patients who underwent complete repair of a tetralogy of Fallot between 2005 and 2011 were retrospectively reviewed. Patients with pulmonary atresia, absence of a pulmonary valve, atrioventricular septal defect and/or subarterial ventricular septal defect were excluded. There were 19 (28%) patients with a severely hypoplastic pulmonary annulus determined by preoperative echocardiography (z-score <-4). For these patients, we collected echocardiographic data and information about their postoperative course.

RESULTS

Valve preserving was successful in 11 of 19 (58%) of the z < -4 group, compared with 48 of 49 (98%) of the z > -4 group. In the z < -4 valve-sparing subgroup (n = 11), the preoperative pulmonary valve diameter z-score was -4.9 (range -6.3 to -4.3), and an approach involving ventriculotomy with no transannular patch was employed at a mean age of 6.9 (range 2.2-16.1) months. In this subgroup, residual right ventricular outflow tract velocity was 2.4 ± 0.6 m/s at discharge from the hospital. During a mean follow-up of 2.6 ± 2.4 years, no reintervention was necessary. Late right ventricular outflow tract velocity was 2.2 ± 0.6 m/s, and there was no severe pulmonary regurgitation. The pulmonary valve annulus grew in relation to the patient's body surface area (z = -0.51, range -4.2-0.24) without any aneurysmal changes in the right ventricular outflow tract.

CONCLUSIONS

Although our modification of valve-sparing repair for severely hypoplastic pulmonary valves in patients with tetralogy of Fallot could not be applied in all patients, this strategy enabled acceptable growth of the valve annulus, with only mild stenosis during the early to mid-term follow-up. This modification seems to be an option, even for a very small pulmonary valve.