Anatomical risk factors for mortality and cardiac morbidity after arterial switch operation

Application of a modified clinical classification for pulmonary arterial hypertension associated with congenital heart disease in children: emphasis on atrial septal defects and transposition of the great arteries. An analysis from the TOPP registry

Aims

A proportion of patients with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) do not fit in the current classification. We aimed to analyse the applicability of an adapted clinical classification of PAH-CHD to pediatric patients using the TOPP-1 registry (Tracking Outcomes and Practice in Pediatric Pulmonary Hypertension) and focus on atrial septal defects (ASD) and transposition of the great arteries (TGA).

Methods and results

Hemodynamic and clinical data of all patients with PAH-CHD in the TOPP cohort were reviewed. Patients were classified according to predefined ABCDE categories (A: Eisenmenger syndrome, B: left-to-right shunt, C: coincidental defects, including all ASDs, D: corrected CHD, E: TGA), or as complex CHD (group 5), by 2 independent investigators. In case of disagreement, a third reviewer could either settle a final decision, or the patient was deemed not classifiable. Survival curves were calculated for each group and compared to idiopathic PAH patients of the registry. A total of 223 out of 531 patients in the registry had PAH-CHD, and 193 were categorized to the following groups: A 39(20%), B 27(14%), C 62(32%) including 43 ASDs, D 58(30%), E 7(4%), whereas 6 patients were categorized as group 5, and 10 patients were unable to be classified. No survival difference could be demonstrated between the groups.

Conclusions

This modified classification seems to be more applicable to pediatric PAH-CHD patients than the previous classification, but some patients with PAH-CHD who never had a shunt remain unclassifiable. The role of ASD in pediatric PH should be reconsidered.

Impact of Coronary Artery Anatomy in Arterial Switch Operation: In-hospital and Post-discharge Outcomes

OBJECTIVE

The influence of the coronary artery anatomy on the prognosis of patients receiving an arterial switch operation (ASO) is currently controversial, and the risk factors for this operation may change in more complicated patients. This study aimed to investigate the influence of coronary artery anomalies on the in-hospital and post-discharge outcomes of ASO in patients with transposition of the great arteries (TGA) and Taussig-Bing anomaly (TBA).

METHODS

We retrospectively reviewed 206 patients who underwent ASO from January 2007 to December 2019. The median age at operation was 33 [interquartile range (IQR): 20-71] days. Median follow-up time was 7.2 years (IQR: 4.0-10.3 years).

RESULTS

Coronary anomalies were present in 86 patients (41.7%), with 9 (4.4%) of them having a single coronary artery. Additional coronary features included intramural courses in 5 (2.4%) patients, ostial stenosis in 1 (0.5%) patient, and accessory coronary artery orifices in 5 (2.4%) patients. There were 32 (15.5%) in-hospital deaths and 8 (4.6%) post-discharge deaths, yielding an overall survival of 81.3%, 80.7% and 79.9% at 1, 5 and 10 years, respectively. Mortality due to ASO has been drastically decreased since 2013. Patients with a single coronary artery had higher rate of in-hospital mortality, but this finding was not statistically significant. The earlier surgical era (OR: 2.756) and a longer cardiopulmonary bypass time (OR: 2.336) were significantly associated with in-hospital mortality, while coronary patterns were not. An intramural coronary artery (HR: 10.034) and a patient age of older than 1 year at the time of ASO (HR: 9.706) were independent predictors of post-discharge mortality.

CONCLUSION

ASO remains the procedure of choice for TGA with coronary anomalies with acceptable in-hospital and post-discharge outcomes in terms of overall survival and freedom of reoperation. However, intramural coronary artery is an independent risk factor for post-discharge mortality. Timely surgery within the 1st year of life helps improve overall midterm survival of ASO.

Nine-Year Experience with the Arterial Switch Operation with Closed Coronary Transfer

BACKGROUND

Coronary artery transfer is a critical step of the arterial switch operation (ASO) for transposition of the great arteries (TGA). Strategies for coronary transfer include open transfer before neo-aortic anastomosis or closed transfer after neo-aortic anastomosis. This study reports outcomes of ASO with closed coronary transfer at a single institution.

METHODS

A retrospective analysis was performed of patients undergoing ASO for TGA from November 2006 to September 2015. Closed coronary transfer was universally employed. Patients were classified into simple versus complex coronary anatomy groups. The primary outcome was overall survival. Secondary outcomes included reoperation-free survival, coronary re-intervention, and aortic insufficiency.

RESULTS

Ninety-six consecutive patients underwent ASO for TGA. Median follow-up was 5.8 years. Thirty-five (36%) of patients had complex coronary anatomy, which was associated with significantly longer cardiopulmonary bypass and aortic cross-clamp time. Overall survival was 97.4%, and reoperation-free survival was 83.6%. There was no difference in survival or reoperation-free survival between patients with simple versus complex coronary anatomy. Hispanic ethnicity, side-by-side great arteries, and urgent or emergent operation were significantly associated with the composite outcome of reoperation or mortality. There were no coronary interventions after ASO, and the incidence of moderate or greater aortic insufficiency was 2.1% at hospital discharge and 1.5% in follow-up.

CONCLUSIONS

Closed coronary transfer during ASO has excellent short and mid-term results. Despite variable and often complex coronary anatomy, coronary ischemic events following ASO are avoidable. Closed coronary transfer has a low risk of aortic valve injury or insufficiency.

Risk Factors for Reoperation After Arterial Switch Operation

OBJECTIVE

The timing and nature of and risk factors for reoperation after the arterial switch operation in the setting of d-transposition of the great arteries requires further elucidation.

METHODS

A total of 403 patients who underwent arterial switch operation from 1986 to 2017 were reviewed. Institutional preference was for pulmonary artery reconstruction using a pantaloon patch of fresh autologous pericardium. The targets for coronary artery reimplantation were identified by intermittent root distension. Multivariable analysis was used to identify risk factors for reoperation.

RESULTS

Median follow-up was 8.6 years (interquartile range [IQR]: 2-16.9). Pulmonary arterioplasty was the most common reoperation (n = 11, 2.7%) at 3.3 years (IQR: 1.4-11.4) postoperatively. Subvalvar right ventricular outflow tract reconstruction (RVOTR) was required in nine (2.2%) patients at 2.5 years (IQR: 1.1-5.3) postoperatively. Aortic valve repair or replacement (AVR/r) was required in seven (1.7%) patients at 13.6 years (IQR: 10.0-15.8) postoperatively. Aortic root replacement (ARR) and Coronary Artery Bypass Graft/coronary patch arterioplasty were required in five (1.2%) patients each at 13.6 years (IQR: 11.0-15.3) and 11.3 years (IQR: 2.3-13.6) postoperatively, respectively. Taussig-Bing anomaly was a risk factor for any reoperation (P = .034). Risk factors for specific reoperations included ventricular septal defect for AVR/r (P = .038), Taussig-Bing anomaly for RVOTR (P = .004), and pulmonary artery banding for ARR (P = .028).

CONCLUSIONS

Pantaloon patch pulmonary artery reconstruction and intermittent neo-aortic root distension during coronary reimplantation have minimized respective outflow tract reoperations. Certain anatomic subsets carry different risks for late reoperation, and pulmonary artery and/or RVOT reinterventions tend to occur sooner than aortic reinterventions. Special attention to these higher risk subpopulations will be critical to optimizing lifelong outcomes.

Outcomes after corrective surgery for congenital dextro-transposition of the arteries using the arterial switch technique: a scoping systematic review

BACKGROUND

Dextro-transposition of the great arteries (D-TGA) is the most frequent cyanotic congenital heart pathology in neonates. Surgical correction of this condition is possible using the arterial switch operation (ASO) which was first performed by Jatene in 1975.

OBJECTIVES

The aim of this study was to summarise the evidence on short- (less than 1 year), medium- (1-20 years), and long-term (more than 20 years) outcomes of children with D-TGA treated with the ASO. The primary outcome was survival. Secondary outcomes were freedom from cardiac reoperations, occurrence of aortic insufficiency, pulmonary stenosis, coronary artery anomalies, neuropsychological development problems and quality of life.

METHODS

We searched MEDLINE, EMBASE, CINAHL, LILACS, and reference lists of included articles for studies reporting outcomes after ASO for D-TGA. Screening, data extraction and risk of bias assessment were done independently by two reviewers. We pooled data using a random-effects meta-analysis of proportions and, where not possible, outcomes were synthesized narratively. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to assess the certainty of the evidence for each outcome.

MAIN RESULTS

Following ASO for TGA, short-term survival was 92.0% (95% CI 91.0-93.0%; I² = 85.8%, 151 studies, 30,186 participants; moderate certainty evidence). Medium-term survival was 90.0% (95% CI 89.0-91.0%; I² = 84.3%, 133 studies; 23,686 participants, moderate certainty evidence), while long-term survival was 87.0% (95% CI 80.0-92.0 %; I² = 84.5%, 4 studies, 933 participants, very low certainty evidence). Evaluation of the different secondary outcomes also showed satisfactory results in the short, medium and long term. Subgroup analysis suggests slightly higher survival following ASO for TGA in the second surgical era (1998 to 2018) than in the first surgical era (1975 to 1997) in the short and medium term [93.0% (95% CI 92.0-94.0) vs 90.0% (95% CI 89.0-92.0) and 93.0% (95% CI 91.0-94.0) vs 88.0% (87.0-90.0%) respectively] but not in the long term [81.0% (95% CI 76.0-86.0%) vs 89.0% (80.0-95.0%)].

CONCLUSIONS

Pooled data from many sources suggests that the ASO for D-TGA leads to high rates of survival in the short, medium, and long term.

Does Coronary Reimplantation After Neoaortic Reconstruction Increase Aortic Regurgitation?

Coronary reimplantation after neoaortic reconstruction (CRANR) in the arterial switch operation (ASO) allows easy selection of accurate coronary transfer sites in the distended neoaorta. However, neoaortic valve injury may occur during coronary reimplantation. We determined whether the CRANR procedure increased the incidence of aortic valve regurgitation (AR) after ASO. Between March 1994 and August 2017, 227 patients underwent ASO. Since September 2000 CRANR has been performed on 155 patients and open coronary reimplantation (OCR) on 72. Patients who had undergone aortocoronary flaps procedures (n = 13), had early or late mortality (n = 27), or lacked data (n = 11) were excluded. We enrolled and retrospectively reviewed the medical records of 176 patients who were followed up for postoperative AR: 38 underwent OCR and 138 underwent CRANR. We compared the incidences of early and late postoperative AR in both groups. We defined mild or greater AR as "significant AR." The groups did not differ in body weight at operation, great artery relationship, and coronary artery anatomy. The incidences of significant AR at discharge were 21.1% (8/38) in the OCR group and 16.6% (23/138) in the CRANR group (p = 0.53). The freedom from significant AR at 5 years was 59.9% in the OCR group and 62.4% in the CRANR group with no difference between the two groups (p = 0.73). Moderate AR occurred in one patient in the CRANR group. No surgical intervention was required for the aortic valve in either group. ASO using the CRANR technique did not increase the incidence of postoperative early and late AR.

Long-term Management of the Arterial Switch Patient

PURPOSE OF REVIEW

This review paper describes the management of patients with dextro-transposition of the great arteries (D-TGA) with a focus on the complications seen and the appropriate care required to identify and prevent adverse events.

RECENT FINDINGS

D-TGA is a form of cyanotic congenital heart disease (CHD) representing ~ 3% of all CHD and almost 20% of all cyanotic CHD. Since the late 1980s, standard of care is to repair these patients with an arterial switch operation (ASO) as opposed to a Mustard/Senning operation. The long-term survival and complication rates are superior in the ASO. Long-term follow-up is recommended for all D-TGA patients and includes management with adult congenital heart disease specialists and the use of echocardiography and advanced imaging with CT or MRI. The most common complications seen are pulmonary stenosis, coronary artery stenosis, and neo-aortic regurgitation. Careful evaluation of new symptoms or declining function is essential in preventing and treating these long-term sequelae.

Development of quality metrics for ambulatory pediatric cardiology: Transposition of the great arteries after arterial switch operation

OBJECTIVE

To develop quality metrics (QMs) for the ambulatory care of patients with transposition of the great arteries following arterial switch operation (TGA/ASO).

DESIGN

Under the auspices of the American College of Cardiology Adult Congenital and Pediatric Cardiology (ACPC) Steering committee, the TGA/ASO team generated candidate QMs related to TGA/ASO ambulatory care. Candidate QMs were submitted to the ACPC Steering Committee and were reviewed for validity and feasibility using individual expert panel member scoring according to the RAND-UCLA methodology. QMs were then made available for review by the entire ACC ACPC during an "open comment period." Final approval of each QM was provided by a vote of the ACC ACPC Council.

PATIENTS

Patients with TGA who had undergone an ASO were included. Patients with complex transposition were excluded.

RESULTS

Twelve candidate QMs were generated. Seven metrics passed the RAND-UCLA process. Four passed the "open comment period" and were ultimately approved by the Council. These included: (1) at least 1 echocardiogram performed during the first year of life reporting on the function, aortic dimension, degree of neoaortic valve insufficiency, the patency of the systemic and pulmonary outflows, the patency of the branch pulmonary arteries and coronary arteries, (2) neurodevelopmental (ND) assessment after ASO; (3) lipid profile by age 11 years; and (4) documentation of a transition of care plan to an adult congenital heart disease (CHD) provider by 18 years of age.

CONCLUSIONS

Application of the RAND-UCLA methodology and linkage of this methodology to the ACPC approval process led to successful generation of 4 QMs relevant to the care of TGA/ASO pediatric patients in the ambulatory setting. These metrics have now been incorporated into the ACPC Quality Network providing guidance for the care of TGA/ASO patients across 30 CHD centers.

Preoperative Intubation and Lack of Enteral Nutrition are Associated with Prolonged Stay After Arterial Switch Operation

Mortality for the arterial switch operation (ASO) has diminished significantly over the past few decades. Some patients do, however, continue to have protracted and complicated courses after surgery. We attempted to determine which preoperative factors were best associated with prolonged hospital stay after ASO. We retrospectively reviewed all patients that underwent an ASO over a 10-year period. Outcomes of patients with postoperative stays (POS) >14 days (long stay group-LS) were compared with those patients with POS < 7 days (short stay group-SS). The following variables were evaluated: age at surgery, weight, septostomy performed (BAS) and management the day prior to surgery including use of prostaglandin E1 (PGE1), inotropes, intubation status and the establishment of enteral feeds. The SS group had 25 patients and the LS group had 32 patients. Both groups (SS vs. LS) were similar in PGE1 use (48 vs. 69 %), BAS (76 vs. 59 %), age at surgery (6 vs. 7 days) and preoperative inotropes (12 vs. 38 %). The SS group had significantly higher incidence of preoperative feeding (80 vs. 31 %, p < 0.001) and less frequent intubation (12 vs. 47 %, p < 0.001). Patients who are intubated and have not yet begun to receive enteral feeds at the time of their ASO are more likely to have prolonged POS. It is unclear if prolonged stays were a result of operating on patients with worse preoperative hemodynamics or a consequence of a preoperative management strategy that did not allow for extubation and establishment of feeds prior to surgery.

Outcomes after Arterial Switch Operation for Simple Transposition

Without intervention, babies born with transposed great arteries (TGA) are doomed to a rapid death. Jatene and coworkers deserve the credit for performing the first successful arterial switch operation (ASO) in a patient with TGA and ventricular septal defect (VSD) in 1975. Since then ASO has become the procedure of choice in most medical centers. This review article summarizes the historical aspects of arterial switch operation and assesses this procedure's outcomes.

Pulmonary Arterial Hypertension and Neonatal Arterial Switch Surgery for Correction of Transposition of the Great Arteries

INTRODUCTION AND OBJECTIVES

There are few reports of the appearance of pulmonary arterial hypertension following arterial switch surgery in the neonatal period to correct transposition of the great arteries. We assessed the frequency and clinical pattern of this complication in our series of patients.

METHODS

Our database was reviewed to select patients with transposition of the great arteries corrected by neonatal arterial switch at our hospital and who developed pulmonary hypertension over time.

RESULTS

We identified 2 (1.3%) patients with transposition of the great arteries successfully repaired in the first week of life who later experienced pulmonary arterial hypertension. The first patient was a 7-year-old girl diagnosed with severe pulmonary hypertension at age 8 months who did not respond to medical treatment and required lung transplantation. The anatomic pathology findings were consistent with severe pulmonary arterial hypertension. The second patient was a 24-month-old boy diagnosed with severe pulmonary hypertension at age 13 months who did not respond to medical therapy.

CONCLUSIONS

Pulmonary hypertension is a rare but very severe complication that should be investigated in all patients with transposition of the great arteries who have undergone neonatal arterial switch, in order to start early aggressive therapy for affected patients, given the poor therapeutic response and poor prognosis involved.

Impact of Coronary Artery Anatomy in Arterial Switch Procedure on Early Mortality and Morbidity

OBJECTIVE

Arterial switch operation has become the treatment of choice for neonates with transposition of the great arteries. The most important step of the procedure is transferring the coronary arteries to the neoaorta successfully. This study shows the impact of coronary anatomy on early mortality and morbidity after arterial switch operation.

METHODS

Ninety-two patients with transposition of the great arteries who underwent arterial switch operation between October 2010 and September 2014 were included in this retrospective study. The patients were classified into two groups: group I (n = 68, patients with usual coronary artery anatomy) and group II (n = 24, patients with unusual coronary artery anatomy). Median age was 10 days (6-25 days) in group I and 14 days (7-29 days) in group II. In group I, 25 patients had ventricular septal defect, nine patients had coarctation of the aorta or distal aortic arch hypoplasia, seven patients had Taussig Bing anomaly. In group II, nine patients had ventricular septal defect, one patient had coarctation of aorta, and one patient had Taussig Bing anomaly.

RESULTS

Regarding the postoperative variables, no significant statistical difference was found between two groups. But cardiopulmonary bypass time is significantly longer in group II (P = .004). There was no difference in complications including the mortality (P = .265). It is statistically found that associated anomalies did not affect the mortality and complication rates. All mortality cases (n = 4) were related to ventricular dysfunction in group II, whereas only four of the eight patients died because of ventricular dysfunction in group I.

CONCLUSION

Coronary artery pattern was not a predictor of mortality in early postoperative period. There may be an impact of unusual coronary artery pattern on the development of ventricular dysfunction as a cause of mortality.

Coronary artery problems late after arterial switch operation for transposition of the great arteries

BACKGROUND

The incidence of late coronary artery abnormalities after arterial switch operation (ASO) for d-loop transposition of the great arteries may be underestimated.

METHODS AND RESULTS

We retrospectively reviewed coronary artery morphology in 40 of 97 patients who survived the first year after ASO. Seven asymptomatic patients developed significant late coronary artery abnormalities. One patient died suddenly at home with severe left coronary artery (LCA) ostial stenosis at age 3.8 years. The second patient collapsed during exercise at age 9.6 years due to ventricular fibrillation and severe LCA ostial stenosis despite prior negative exercise stress test (EST) and myocardial perfusion imaging (MPI). The third patient was found to have moderate ostial stenosis of the LCA with negative EST and MPI. The fourth patient with exercise-induced ST-T depression and myocardial perfusion defect was shown to have complete LCA occlusion with collateral vessel formation. Three other patients had complete proximal obliteration of either of the coronary arteries with collateral supply. An additional 4 asymptomatic patients had trivial-mild narrowing of the LCA on routine selective coronary angiogram.

CONCLUSIONS

Incidence of late coronary stenosis or occlusion was not infrequent after ASO (11.3%) and presented usually without preceding symptoms and often after negative non-invasive screening. We advocate routine coronary imaging in all patients after ASO before they participate in competitive sports.

Unroofing intramural coronary artery for late coronary events after arterial switch operation

The incidence of intramural coronary arteries in patients with transposition of the great arteries is relatively rare. Intramural coronary arteries are highly associated with early and late coronary adverse events. We report a case of late coronary events caused by an intramural left coronary artery, which was successfully treated by the unroofing procedure.

Managing the posterior coronary loop in the arterial switch operation: the 'inverse flap' technique

Posterior coronary looping remains a risk factor when performing an arterial switch operation for transposition of the great arteries. In such a situation, to avoid the risk of overstretching, we use an 'inverse' flap technique, resulting in a tension-free relocation.

Abnormal mitral valve anatomy in d-transposition of the great arteries: anatomic characterization and surgical outcomes

Mitral valve anomalies can occur with S,D,D-transposition of the great arteries (d-TGA). Their influence on surgical technique and outcome after an arterial switch operation (ASO) has not been well described. Patients with d-TGA who underwent ASO from February 1990 to January 2011 were identified. Echocardiograms, operative reports, hospital course, and latest follow-up evaluation were reviewed. A total of 218 infants underwent ASO at a median age of 15.8 days. Survival was 95 % during a mean follow-up period of 60 months. Nine patients (4 %) were found to have similar mitral valve anomalies including anterior malalignment conoventricular septal defect, anterior displacement of the mitral valve toward the left ventricular outflow tract (LVOT), malpositioning of the posteromedial papillary muscle, unusual rotation of the mitral valve leaflets orienting the commissure toward the anterior ventricular septum, and redundant mitral valve tissue extending into the LVOT. Coarctation was more frequent in this subgroup (33 vs. 10 %; p = 0.05). Preoperative echocardiography consistently indicated suspicion of a cleft mitral valve with chordal attachments to the ventricular septum causing potential LVOT obstruction. Operative inspection did not identify a cleft or anomalous attachments in any patient, and no valvuloplasty or chordal manipulation was performed. The average hospital length of stay were similar (30.7 vs. 25.3 days; p = 0.54). One patient died late due to progressive LVOT obstruction, and one required heart transplantation. No patient had significant mitral valve regurgitation. We conclude that mitral valve anomalies associated with d-TGA are rare but present with consistent anatomic features and higher risk of coarctation. Unusual mitral valve apparatus positioning and chordal redundancy can suggest the need for valvuloplasty and chordal resection preoperatively, but this is rarely needed.

Midterm results after arterial switch operation for transposition of the great arteries: a single centre experience

Background

The arterial switch operation (ASO) has become the surgical approach of choice for d-transposition of the great arteries (d-TGA). There is, however an increased incidence of midterm and longterm adverse sequelae in some survivors. In order to evaluate operative risk and midterm outcome in this population, we reviewed patients who underwent ASO for TGA at our centre.

Methods

In this retrospective study 52 consecutive patients with TGA who underwent ASO between 04/1991 and 12/1999 were included. To analyze the predictors for mortality and adverse events (coronary stenoses, distortion of the pulmonary arteries, dilatation of the neoaortic root, and aortic regurgitation), a multivariate analysis was performed. The follow-up time was ranged from 1–10 years (mean 5 years, cumulative 260 patient-years).

Results

All over mortality rate was 15.4% and was only observed in the early postoperative period till 1994. The predictors for poor operative survival were low APGAR-score, older age at surgery, and necessity of associated surgical procedures. Late re-operations were necessary in 6 patients (13.6%) and included a pulmonary artery patch enlargement due to supravalvular stenosis (n = 3), coronary revascularisation due to coronary stenosis in a coronary anatomy type E, aortic valve replacement due to neoaortic valve regurgitation (n = 2), and patch-plasty of a pulmonary vein due to obstruction (n = 1). The dilatation of neoaortic root was not observed in the follow up.

Conclusions

ASO remains the procedure of choice for TGA with acceptable early and late outcome in terms of overall survival and freedom of reoperation. Although ASO is often complex and may be associated with morbidity, most patients survived without major complications even in a small centre.

[Prognostic evaluation of arterial switch in the transposition of great arteries]

INTRODUCTION AND OBJECTIVES

The arterial switch is the procedure of choice for transposition of great arteries, with or without ventricular septal defect. The aim of this study was to identify risk factors for hospital mortality.

METHODS

The study included 121 children between January 1994 and June 2008. Of these, 80 (66%) were diagnosed with intact ventricular septum, and 41 (34%) with ventricular septal defect. Variables were collected pre-operatively, during surgery, and postoperatively.

RESULTS

The mean age was 11 [8 to 16] days and a mean weight of 3.5 [3.0 to 3.7] kg. A ventricular septal defect was closed in 11 children (9.1%). A total of 81.8% had a normal coronary pattern. There was delayed closure of the chest in 38 patients (31.4%). The hospital mortality was 11.6%, decreasing over the past 5 years to 2.1%. The weight, abnormal coronary pattern, time of cardiopulmonary bypass, mean arterial pressure at admission, pulmonary dead space, and delayed closure of the chest, were risk factors of mortality. The model that best predicts death, consists of the mean arterial pressure at admission, and delayed closure of the chest.

CONCLUSIONS

The reduction in extracorporeal circulation time and the use of delayed closure of the chest, have helped to reduce mortality. The abnormal coronary pattern remains a risk factor for mortality. In children with delayed closure of the chest, a mean arterial pressure at admission ≥ 47.5 mmHg is a goal to achieve.

Safety and efficacy of arterial switch operation in previously inoperable patients

BACKGROUND

Patients older than six months with complete transposition of the great arteries and ventricular septal defect or Taussig-Bing anomaly and severe pulmonary arterial hypertension (PAH), previously thought to be inoperable, usually are not indicated for arterial switch operation (ASO) or even repair. This study aimed to evaluate the safety and efficacy of ASO in these selected subset patients.

METHODS

The records of 86 patients older than six months with complete transposition of the great arteries and ventricular septal defect or Taussig-Bing anomaly and severe PAH who underwent ASO at our institution from May 2000 to October 2008 were reviewed retrospectively. Eighty survivors were followed-up.

RESULTS

There were six hospital deaths (7.0%, 95% confidence limit 1.6 to 12.4%). From January 2006 to October 2008, 46 consecutive ASOs were performed with no death. Operative mortality and mobility decreased significantly (p = 0.008 and p = 0.046, respectively). The median duration of follow-up was 42.1 +/- 28.8 months (range, 2.0 to 99.5). Two late deaths occurred. Latest follow-up data showed that 2.8% of survivors were in New York Heart Association (NYHA) class II and 97.2% were in NYHA class I.

CONCLUSIONS

Excellent early and mid-term results of ASO are obtained from patients older than six months with complete transposition of the great arteries and ventricular septal defect or Taussig-Bing anomaly and severe PAH in current era, and ASO is safe and effective in these selected subset patients.

Late-onset pulmonary arterial hypertension after a successful atrial or arterial switch procedure for transposition of the great arteries

Common complications after surgery for transposition of the great arteries (TGA) include systemic ventricular dysfunction and arrhythmia after atrial baffle repair (AB) and outflow tract stenosis or regurgitation after the arterial switch (AS). Severe pulmonary hypertension (PHT) is a rarely reported problem after AB and AS. In this study we sought to evaluate the frequency of late onset severe PHT following surgical repair for TGA. We report 3 cases, 2 after AB and 1 after AS, describe the frequency of this complication and treatment response, by comparing the response to pulmonary vasodilators in this group of patients to that of idiopathic or connective tissue disease (CTD) related PHT. We currently follow 85 patients >or=17 years of age with repaired TGA; 77 after AB and 8 after AS. 3.5% of our adult congenital heart disease patients with TGA have developed late severe PHT. None of these patients demonstrated clinical improvement with Bosentan at 6 months, however 2 of 3 were stabilised with the addition of Sildenafil to initial therapy. The third patient died 4 months after the diagnosis of severe PHT, whilst waiting for heart-lung transplantation, despite Bosentan, Sildenafil and inotropic support. By contrast, of 37 patients with idiopathic or CTD related PHT commenced on Bosentan as initial therapy, 32 (86.5%) demonstrated a clinical response at 6 months; the other patients had Sildenafil as added therapy after 6 months. Our data suggest that patients with TGA and late onset PHT are less likely to achieve a clinical response on pulmonary vasodilator monotherapy (P = 0.006). Whilst more investigation is needed, our experience suggests an aggressive clinical course, often requiring combination PHT treatment.

Effect of modified ultrafiltration on postoperative course in neonates with complete transposition of the great arteries undergoing arterial switch operation

BACKGROUND

The purpose of the present study was to evaluate the effect of modified ultrafiltration (MUF) on neonates with transposition of the great arteries (TGA) undergoing arterial switch operation.

METHODS AND RESULTS

The current study included 36 neonates who underwent an arterial switch operation between 1998 and 2006. Arterio-venous MUF was done in 15 patients (MUF-treated group) and the other 21 patients were controls. Parameters included hematocrit, hemodynamics, pulmonary function, drain loss, leak of peritoneal fluid, length of intubation, and intensive care unit (ICU) stay. The hematocrit increased from 34+/-2% to 47+/-4% in the MUF-treated group. Blood pressure in the MUF-treated group was significantly increased without any change of central venous or left atrial pressure. Post-operative oxygenation in the MUF-treated group was greater than that of the control group (P/F ratio: 258+/-92 vs 170+/-100 mmHg, p<0.05), which did not contribute to decrease in intubation time (54+/-33 vs 52+/-29 h, p=NS). Post-operative chest drain loss and peritoneal fluid leak were comparable. The ICU stay in the MUF-treated group was significantly shorter than that in the controls (101+/-34 vs 139+/-42 h, p<0.05).

CONCLUSIONS

MUF brought improvement in blood pressure and gas exchange capacity and subsequent shorter ICU stay. MUF did not have significant impact on intubation time and capillary leak.

Cardiac Outcome up to 15 Years After the Arterial Switch Operation

AIMS

To assess the cardiac outcome and risk factors for mortality of infants following the arterial switch operation (ASO).

METHODS

A single-centre retrospective review was conducted. Preoperative assessment, operative management and outcome was detailed for 244 patients undergoing the ASO at Green Lane Hospital for transposition of the great arteries (TGA) or double outlet right ventricle.

RESULTS

The postoperative survival at 1, 5 and 15 years was 85%, 84% and 83%, respectively. The calendar year of ASO and the presence of a ventricular septal defect (VSD) were the primary predictors of early mortality. Late mortality was associated with a side-by-side configuration of the great arteries. Re-intervention following ASO was more common in patients with prolonged cardiopulmonary bypass time.

CONCLUSIONS

Low early and late morbidity and mortality can be obtained in infants with TGA or double outlet right ventricle by definitive repair utilising the ASO.

Late results after extended pulmonary artery reconstruction in the arterial switch operation

BACKGROUND

Pulmonary artery stenosis remains the most frequent late complication and cause of reintervention after the arterial switch operation for transposition of the great arteries. We investigated the influence of an extended pericardial patch augmentation of the neopulmonary root and pulmonary artery on late pulmonary artery stenosis development.

METHODS

Augmentation of the neopulmonary root and pulmonary artery was achieved by reconstructing the posterior wall using a large glutaraldehyde-treated autologous pericardial patch. Reviewed were regular follow-up echocardiograms from 58 out of 87 patients undergoing the arterial switch operation who presented a follow-up period of at least 5 years. An actual follow-up echocardiographic evaluation focusing on the maximal instantaneous transpulmonary continuous-wave (cw)-Doppler gradient was performed, followed by cardiac catheterization when indicated (peak cw-Doppler gradient > 40 mm Hg).

RESULTS

Follow-up was 8.9 [5 to 15] years. There was no reintervention due to residual pulmonary artery stenosis. Actual Doppler examination revealed a transpulmonary peak gradient of 19.5 [0 to 56] mm Hg, compared with 20 [0 to 60] mm Hg at discharge. Forty-three patients (74.1%) had no or only trivial pulmonary artery stenosis (pressure gradient < 25 mm Hg), 14 patients (24.2%) had mild stenosis (25 to 49 mm Hg), and 1 patient (1.7%) had moderate stenosis (50 to 79 mm Hg).

CONCLUSIONS

Compared with the majority of literature data, we could demonstrate a low incidence of late pulmonary artery stenosis after the arterial switch operation by employing an extended pericardial patch reconstruction technique with augmentation of the neopulmonary root and pulmonary artery.

Cardiac Troponin T Levels for Risk Stratification in Pediatric Open Heart Surgery

BACKGROUND

Cardiac troponin T has been found to be accurate predictor of complications and adverse clinical events after pediatric cardiac surgery. Contrary to adult cardiac surgery, the relationship of troponin T to patient survival after pediatric heart surgery has not been previously studied. The purpose of this study was to determine whether troponin T could predict death after pediatric open cardiac surgery.

METHODS

This was a retrospective cohort study in which data from 1001 consecutive children having cardiac surgery during a 5-year period were studied. Perioperative variables that could influence death at 30 postoperative days were evaluated.

RESULTS

Multivariate analysis, using a forward stepwise logistic regression, showed that troponin T measured on the first postoperative day was a strong independent predictor of death at 30 days. Level of troponin T greater than 5.9 microg/L on the first postoperative day predicted death (odds ratio, 10.7; 95% confidence interval: 5.2 to 22.1) as did admission lactate level greater than 5.2 mmol/L (odds ratio, 22.2; 95% confidence interval: 9.7 to 50.8) No other variable, including postoperative creatine kinase-MB mass concentration, age, diagnosis, surgical procedure, presence of cyanosis, chromosomal anomaly or ventriculotomy, duration of cardiopulmonary bypass, or aortic cross-clamp, had any independent effect on 30-day survival.

CONCLUSIONS

Cardiac troponin T level on the first postoperative day is a powerful independent risk marker of death in pediatric cardiac surgery.

Neo-aortic valvar function after the arterial switch

OBJECTIVES

The purpose of our study was to assess the prevalence and progression, during childhood and adolescence, of dilation of the neo-aortic root, and neo-aortic valvar regurgitation, and to identify risk factors for such dilation and regurgitation, after the arterial switch operation.

METHODS

We included all patients who had undergone an arterial switch operation at The Children's Hospital of Philadelphia, and had been followed for a minimum of 4 years, and had at least 2 postoperative echocardiograms. Neo-aortic valvar regurgitation was quantitatively assessed, and measurements were made of the neo-aortic root at the level of the basal attachment of the leaflets, mid-sinusal level, and the sinutubular junction.

RESULTS

We found 82 patients who satisfied the criterions for inclusion, of whom 52 patients had transposition with an intact ventricular septum, and 30 had either an associated ventricular septal defect or double outlet right ventricle. The median follow-up time was 8.8 years (4.1 to 16.4 years). The neo-aortic valve had been replaced in 1 patient. Of the patients, 3 had moderate, 66 had trivial to mild, and 12 had no neo-aortic valvar regurgitation at their most recent follow-up. The regurgitation had progressed by at least 1 grade in 38 of the 82 patients (46.4%). Neo-aortic dilation was noted at the basal attachment of the leaflets, and at mid-sinusal level, which was out of proportion to somatic growth.

CONCLUSIONS

At mid-term follow-up, significant neo-aortic valve regurgitation is present in 3.7%, and trivial to mild regurgitation in 81.4% of patients. The regurgitation progressed in almost half of the patients over time. We also noted progressive dilation of the neo-aortic root out of proportion to somatic growth.

Aortic valve regurgitation after arterial switch operation for transposition of the great arteries: incidence, risk factors, and outcome

OBJECTIVES

The aims of this study were to assess the prevalence and incidence of aortic valve regurgitation (AR) after arterial switch operation (ASO), its outcome, and the risk factors.

BACKGROUND

After an ASO, the long-term fate of the aortic valve is a concern as follow-up lengthens.

METHODS

Operative and follow-up data on 1,156 hospital survivors after ASOs between 1982 and December 2000 were reviewed.

RESULTS

At last follow-up (mean duration 76.2 +/- 60.5 months), 172 patients (14.9%) had an AR. Complex transposition of the great arteries, prior pulmonary banding done in 75 patients (21 with intact ventricular septum), aortic arch anomalies, AR at discharge, older age at ASO, and aortic/pulmonary size discrepancy were associated with AR. On multivariate analysis, the presence of a ventricular septal defect (VSD) or AR at discharge multiplied the risk by 2 and 4, respectively. Freedom from AR was 77.9% and 69.5% at 10 and 15 years, respectively; hazard function for AR declined rapidly and slowly increased thereafter. Reoperation from AR was done in 16 patients with one death, valvuloplasty being unsuccessful. Freedom from reoperation for AR was 97.7% and 96.8% at 10 and 15 years, respectively; hazard function slowly increased from 2 to 16 years. Higher late mortality was not associated with AR.

CONCLUSIONS

After ASO, AR was observed and was related to VSD with attending high pressure and flow and AR at discharge. Progression of AR was slow, but incidence increased with follow-up. Reoperation for AR was rare. Late aortic valve function warrants long-term monitoring.

Long-Term Results After Primary One-Stage Repair of Transposition of the Great Arteries and Aortic Arch Obstruction

OBJECTIVES

The study was designed to evaluate perioperative and late results after primary, single-stage arterial switch operation (ASO) associated with aortic arch obstruction repair. Outcome of patients with more than five years of follow-up were analyzed.

BACKGROUND

The treatment of patients with transposition of the great arteries, or other forms of ventriculoarterial discordance suitable for an ASO, with coexisting arch obstruction is a difficult task. Single-stage repair has become the treatment of choice at many institutions, but large series with long-term results are seldom reported.

METHODS

Between 1990 and 1998, a primary operation including aortic arch repair through a midline sternotomy was performed in 38 patients. The relief of arch obstruction was accomplished during a period of hypothermic circulatory arrest, employing a wide pericardial patch to enlarge the inner curvature of the entire arch in most patients.

RESULTS

There were nine (24%) hospital deaths. None could be directly related to aortic arch repair, but additional risk factors for an ASO were common (right ventricular hypoplasia, complex coronary anatomy, uncommon relationship between the great vessels or severe pulmonary hypertension). There were no late deaths. Four patients required cardiac reoperation, whereas three underwent successful treatment of recurrent coarctation with balloon angioplasty.

CONCLUSIONS

Infants with ventriculoarterial discordance and aortic arch obstruction represent a high-risk subgroup of candidates for an ASO. Despite a non-negligible operative mortality, single-stage primary repair represents the treatment of choice, and follow-up of operative survivors is favorable. Pericardial patch enlargement is a reliable technique for arch obstruction repair.

Arterial switch operations for single coronary artery ostium or intramural coronary artery

BACKGROUND

Successful transfer of the coronary arteries is the most critical step during arterial switch operations for patients with transposition of the great arteries with a single coronary artery ostium and/or intramural coronary arteries. Various techniques have been reported and the present study was an evaluation of them in 10 neonatal patients.

METHODS AND RESULTS

Coronary artery transfers are achieved by implantation of coronary buttons to the previously anastomosed neo-aorta using pericardial or pulmonary artery hood techniques. One patient died perioperatively because of myocardial malperfusion. Following prolonged mechanical ventilation, another died from sepsis on the 28th postoperative day. Coronary artery perfusion abnormality was not observed in the remaining patients.

CONCLUSIONS

Transfer of the coronary button by the pericardial or pulmonary artery hood augmentation technique to the previously anastomosed neo-aorta is a practical, easy and convenient combination of methods for the treatment of these patients.

Left-sided lesions after anatomic repair of transposition of the great arteries, ventricular septal defect, and coarctation: Surgical factors

OBJECTIVE

This study was undertaken to identify potential anatomic and surgical factors creating left-sided lesions, namely recoarctation of the aorta and neoaortic regurgitation, after anatomic repair of transposition of the great arteries with ventricular septal defect and aortic coarctation.

METHODS

From 1983 to September 2002, 109 survivors out of 120 patients were studied. Two-stage repair was performed in 42 patients (group A), and single-stage repair was performed in 67 (groups B and C). Before repair, the diameters of the ascending aorta and main pulmonary artery were measured. In the patients with single-stage repair, coarctation was repaired by extended end-to-end anastomosis in 35 patients (group B) and by pulmonary homograft patch augmentation in 32 patients (group C). The ventricular septal defect was closed through the pulmonary artery in 70 patients and through the right ventricle or atrium in 39 patients. The neoaorto-aortic discrepancy was treated by V-shaped resection of the posterior sinus of Valsalva in 7 cases, pulmonary homograft patch in 32 cases, and anterior splitting of the ascending aorta in all cases. Before discharge from the hospital, neoaortic root and ascending aorta diameters and aortic regurgitation grade were recorded. Neoaortic regurgitation progression and reintervention were the end points of follow-up (97.2 +/- 61.2 months).

RESULTS

Early and late survivals were significantly better in group C (P <.001). Risk factors for neoaortic regurgitation at discharge by univariate analysis were single-stage repair (P <.05) and ventricular septal defect closure through the pulmonary artery (P =.0076). On multivariate analysis, the latter was the only risk factor for neoaortic regurgitation at discharge and at last follow-up. Multivariate analysis showed that higher neoaortic root/ascending aorta ratio and ventricular septal defect closure through the pulmonary artery were risk factors for neoaortic regurgitation evolution at last follow-up. There were 29 reinterventions, 19 for recoarctation of the aorta and 10 for neoaortic regurgitation with or without aortic root dilatation. Group B (P <.05), high neoaortic root/ascending aorta ratio (P <.01), and progressive neoaortic regurgitation (P <.05) were risk factors for recoarctation of the aorta. Group A was a risk factor for aortic valve replacement at 10 years (P <.05).

CONCLUSION

Neonatal single-stage repair with pulmonary homograft aortic augmentation remains the optimal approach to transposition of the great arteries with ventricular septal defect and aortic coarctation. It provides better early and late survivals and freedoms from left-sided lesions. Avoidance of late recoarctation of the aorta and progressive neoaortic regurgitation requires meticulous closure of the ventricular septal defect and evenly sized reconstruction of the aorta from root to distal arch.

Current expectations for newborns undergoing the arterial switch operation

BACKGROUND

The arterial switch operation (ASO) represents a remarkable success story in the surgical treatment of cyanotic congenital heart disease. This study is designed to assess recent outcomes after the ASO in babies presenting with transposition of the great arteries (TGA) and Taussig-Bing anomaly (TBA).

METHODS

One hundred twenty-five consecutive neonatal and infant ASOs were performed by 2 surgeons at Texas Children's Hospital between July 1, 1995 and October 1, 2003. Patients with TGA and TBA were offered ASO irrespective of patient size and associated cardiac malformations. Primary cardiac diagnoses included TGA with intact ventricular septum (TGA/IVS, n = 79, 63%), TGA with ventricular septal defect (TGA/VSD, n = 37, 30%), and Taussig Bing Anomaly (TBA, n = 9, 7%).

RESULTS

With complete follow-up, we observed a 30-day mortality rate of 1.6% (n = 2) with 2 late deaths (1.6%), for an overall actuarial survival rate of 96.3% at 7 years. Although there was a significant incidence of complex coronary ostial origin and branching including single coronary (n = 8, 6.4%) and intramural coronary artery (n = 8, 6.4%), this was not associated with increased operative risk. All patients are fully saturated and NYHA functional class I at latest clinic visit (0.3 to 88.4 months postoperatively). There have been no late coronary events. Of 121 survivors, 7 patients (5.8%) have required cardiovascular reoperation at an average of 15.3 +/-11.7 months postoperatively (range, 3.6 to 30.6 months) for an actuarial freedom from reoperation of 90% at 7 years.

CONCLUSIONS

Using current methodologies, the ASO can be performed safely and with a low incidence of need for reoperation on intermediate follow-up. Recent experience indicates operative survival rates approaching 100%.