Long-term survival and functional follow-up in patients after the arterial switch operation

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.

Twenty-eight years' experience of arterial switch operation for transposition of the great arteries in a single institution

OBJECTIVES

We reviewed our 28 years of experience of arterial switch operation (ASO) for transposition of the great arteries to investigate late sequelae of this procedure.

METHODS

387 patients who underwent ASO from 1984 to 2010 were included in this retrospective study. The longitudinal data were estimated by the Kaplan-Meier method and compared using a log-rank test. Risk factors for late sequelae were analysed by the multivariable Cox proportional hazards model.

RESULTS

The mean follow-up time was 10.0 years. There were 13 early deaths and 17 late deaths. All late deaths were within 1 year, except for three patients. Actuarial survival was 92.2 and 91.6% at 10 and 20 years, respectively. Sixty-six patients (17.1%) had developed pulmonary stenosis (PS) and 29 patients (7.5%) had developed moderate or more aortic insufficiency (AI) during follow-up. Selective coronary angiography was performed in 210 patients (54.3%) at 9.6 ± 5.1 years after ASO. Left main tract occlusion was found in 2 patients (2/210; 1.0%) and hypoplastic left coronary artery was found in 10 patients (10/210; 4.8%). Among these 12 patients, 8 patients were asymptomatic. Re-operation was performed in 76 patients (19.6%), pulmonary artery plasty for PS in 58 patients (15.0%), aortic valve replacement for AI including two Bentall operations in 9 patients (2.3%) and others. Freedom from re-operation was 78.2 and 62.8% at 10 and 20 years, respectively. The risk factor for PS was the use of equine pericardium for reconstruction (P < 0.0001). Factors associated with moderate or more AI was the presence of left ventricular outflow tract obstruction (P = 0.004). There were no risk factors for late coronary lesions. Three hundred and forty surviving patients (340/357; 95.2%) were in NYHA functional class I. Treadmill test, which was performed on 217 patients (56.1%) at 14.3 ± 5.4 years after ASO, revealed that the maximum heart rate was 97.5 ± 7.6% of normal and peak oxygen consumption was 105.2 ± 20.5% of normal.

CONCLUSIONS

ASO was performed with satisfactory results in the overall survival and functional status. PS was the main reason for re-operation. Coronary lesions can appear late without any symptoms. Benefits of ASO can be achieved by long-term follow-ups of PS, AI and coronary lesions.

Thirty-year experience with the arterial switch operation

BACKGROUND

We evaluated the results of the arterial switch operation (ASO) being performed at our institution for more than 30 years and identified risk factors for mortality and reoperation.

METHODS

Clinical outcome of 332 consecutive patients with transposition of the great arteries undergoing ASO was retrospectively analyzed, using surgical reports, medical charts, and latest follow-up echocardiography. Statistical analysis was performed using the Kaplan-Meier method and univariable and multivariable binary logistic and Cox regression analyses.

RESULTS

In-hospital mortality was 11.4%. At 15 years, estimated overall survival was 85.2%, and estimated freedom from reoperation was 74.0%. Cross-clamp time (p=0.001) and absence of the Lecompte maneuver (p=0.001) were identified as independent risk factors for in-hospital mortality, whereas coronary problems during surgery (p=0.009) and postoperative pacemaker implantation (p<0.001) were independent risk factors for late mortality. Independent risk factors for reoperation were higher age at the time of the ASO (p=0.002), presence of arch abnormalities (p<0.001), coronary problems during surgery (p=0.005), and duration of ventilation (p<0.001). At latest echocardiography, moderate or severe neoaortic regurgitation was present in 3.4% of the patients.

CONCLUSIONS

Overall, 30 years of experience with the ASO shows good survival and event-free survival rates. Coronary transfer problems during surgery were found to be an important risk factor for late mortality and reoperation. However, coronary anatomy other than 1LCx-2R and an intramural course of the left coronary artery or left anterior descending artery were not risk factors for mortality or reoperation. Neoaortic regurgitation does not seem to form a major problem.

The arterial switch operation: 25-year experience with 258 patients

BACKGROUND

At our institution, the arterial switch operation for transposition of the great arteries has transitioned from the Gore-Tex patch (W.L. Gore & Associates, Flagstaff, AZ) for pulmonary artery reconstruction to redundant pantaloon pericardial patch (RPPP). The (U-shaped) coronary artery button was used for coronary reimplantation. This study investigates overall mortality and factors for neopulmonary artery, neoaortic, and coronary artery surgical reintervention.

METHODS

We performed a retrospective chart review of all patients who underwent arterial switch between 1983 and 2007. Our surgical database, operative reports, and cardiology clinic charts were reviewed. Time to event was plotted as Kaplan-Meier curves. Predictors of time-to-event were examined using Cox proportional hazard modeling.

RESULTS

A total of 258 patients underwent arterial switch during the study. Mortality declined from 15% (era I: 1983 to 1990) to 11% (era II: 1991 to 1998) to 7% (era III: 1999 to 2007). Era III had a significantly later time to death compared with era I (hazard ratio [HR] 0.62, p = 0.04). The RPPP had a lower neopulmonary artery reintervention rate compared with Gore-Tex; 9 of 225 (4%) versus 3 of 21 (14%), p = 0.008. Complex anatomy increased risk for neopulmonary reintervention (HR 3.3, p = 0.03). Surgical reintervention rate for coronary arteries was 2%. Complex coronary anatomy (HR 17.9, p = 0.01) predicted coronary reintervention. Predictors of neoaortic reintervention were prior pulmonary artery band (HR 4.3, p = 0.03), complex anatomy (HR 3.5, p = 0.01), and coronary artery anatomy (HR 3.5, p = 0.04).

CONCLUSIONS

Arterial switch operation mortality has decreased. Conversion to RPPP reduced neopulmonary artery reintervention. The (U-shaped) coronary artery button technique is associated with low coronary reintervention rates. Complex coronary anatomy increases coronary and aortic reintervention. Prior pulmonary artery banding and complex anatomy increase aortic reintervention.

Is the function of all cardiac valves after the arterial switch operation influenced by an associated ventricular septal defect?

A ventricular septal defect in transposition of the great arteries is frequently closely related to the cardiac valves. The valvar function after arterial switch operation of patients with transposition of the great arteries and ventricular septal defect or intact ventricular septum was compared. We analysed the function of all cardiac valves in patients who underwent the arterial switch operations pre- and post-operatively, 1 year after the procedure and on follow-up. The study included 92 patients - 64 with transposition of the great arteries/intact ventricular septum and 28 with transposition of the great arteries/ventricular septal defect. The median age at surgery was 5.5 days in transposition of the great arteries/intact ventricular septum (0-73 days) and 7.0 days in transposition of the great arteries/ventricular septal defect (4-41 days). Follow-up was 51.7 months in transposition of the great arteries/intact ventricular septum (3.3-177.3 months) and 55 months in transposition of the great arteries/ventricular septal defect (14.6-164.7 months). Neo-aortic, neo-pulmonary, and mitral valvar function did not differ. Tricuspid regurgitation was more frequent 1 year post-operatively in transposition of the great arteries/ventricular septal defect (n = 4) than in transposition of the great arteries/intact ventricular septum. The prevalence of neo-aortic regurgitation and pulmonary stenosis increased over time, especially in patients with transposition of the great arteries/intact ventricular septum. The presence of a ventricular septal defect in patients undergoing arterial switch operation for transposition of the great arteries only has a minor bearing for the development of valvar dysfunction on the longer follow-up.

Late Complications Following the Arterial Switch Operation

The arterial switch operation has been the principal treatment for transposition of the great arteries and its variants for the last 25 years. Early mortality has decreased significantly over time, but long-term complications include pulmonary artery stenosis, coronary artery obstruction, neoaortic valvar insufficiency, arrhythmia, and aortic arch obstruction. This article provides an overview of the history, anatomic patterns, surgical results, and possible operative solutions discussed in the literature for patients with transposition of the great arteries who undergo arterial switch operations that result in late complications. Published journal articles were identified through PubMed literature search. The authors selected 72 articles for analysis. It is concluded that modifications can be made to the arterial switch operation in an effort to meet the challenges presented by late complications.

Neoaortic Valve Function 10 to 18 Years After Arterial Switch Operation

Anatomical correction is a procedure of choice for transposition of the great arteries (TGA) in neonates. During surgery, the aorta and pulmonary artery are switched—the native pulmonary valve becomes the neoaortic valve. The fate of this valve remains uncertain. Many reports suggest that its ability to function worsens with time after surgery. Of 519 patients with TGA operated on between 1991 and 2008, 161 met inclusion criteria for this retrospective study and were followed 10 years or more to assess neoaortic valve regurgitation (NeoAR) occurrence and development and to estimate potential risk factors. The subjects were divided into 2 groups: group 1 (simple TGA) and group 2 (TGA + ventricle septal defect). Within the analyzed group, the frequency of significant regurgitation increased from 9% 1 year after the operation to 47% at the most recent follow-up. No severe regurgitation necessitating reoperation was observed. Analysis of potential risk factors revealed that pulmonary/aortic valve diameter discrepancy and nonfacing commissures were associated with increased risk of development of neoaortic insufficiency. NeoAR arises and develops over time after correction of the defect. No hemodynamic repercussions necessitating cardiac surgical interventions were observed. The majority of insufficiencies are detected between 2 and 6 years after surgery. The degree of incompetence is usually mild and increases during follow-up by about 0.5 or 1 degree. The risk factors for NeoAR appearance are pulmonary artery/aortic annulus discrepancy and nonfacing commissures.

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.

Long-term outcomes after an arterial switch operation for simple complete transposition of the great arteries

BACKGROUND AND OBJECTIVES

Although coronary artery obstruction, aortic insufficiency (AI), and pulmonary stenosis (PS) have been reported after arterial switch operation (ASO), limited long-term studies on ASO exist. Our study aimed to examine long-term outcomes after ASO for simple complete transposition of the great arteries (TGA).

SUBJECTS AND METHODS

All 108 patients with simple complete TGA who underwent ASO at Seoul National University Children's Hospital between 1987 and 2004 were enrolled. We retrospectively reviewed the patients' medical records and the results of various functional and imaging studies.

RESULTS

Among 108 cases of ASO for simple TGA, 96 have been followed-up through the present time (mean follow-up duration was 11.7+/-8.6 years: range= 4 to 23 years). The 20-year rates of freedom from significant AI, PS, and coronary obstruction were 78.6%, 67.8%, and 95.8%, respectively. AI showed a tendency to progress as follow-up time increased in 21.4% of the population studied (p=0.014); however, AS, PS, and PI showed no such progression. Late coronary artery occlusion was not associated with the initial coronary arterial pattern. Re-operations were done for 13 patients (13.5%) at an average of 8+/-4.3 years after ASO. The survival rate was 96%, while the re-operation-free was 90% at 10 years and 83% at 20 years. Most patients showed normal physical growth with good activity {98%; New York Heart Association (NYHA) class 1 activity} and normal development (96%).

CONCLUSION

Although most patients showed normal physical growth and development after successful ASO, meticulous long-term follow-up is necessary because of progressive AI and coronary complications.

Mortality associated with adult congenital heart disease: Trends in the US population from 1979 to 2005

BACKGROUND

Significant advances over the last 5 decades have allowed most patients with congenital heart disease to survive well past childhood and into adulthood. Population-based data from the United States are limited regarding mortality in adult survivors.

METHODS

We used the Center for Disease Control Multiple Cause-of-Death registry to determine trends in mortality from 1979 to 2005 among individuals with congenital heart disease in the United States.

RESULTS

There were significant reductions in death rates for adults with a number of congenital defects including ventricular septal defect, patent ductus arteriosus, coarctation of the aorta, and Ebstein anomaly. Notably, when all ages were analyzed, there was a 71% decline in deaths associated with transposition of the great arteries (P = .001) and a 40% reduction in deaths associated with tetralogy of Fallot (P < .001). Mortality related to other lesions declined as well. Among adults with cyanotic lesions, the primary contributing cause of death was arrhythmia followed by heart failure. For adults with noncyanotic lesions, the major contributing cause before 1990 was arrhythmia; after 1990, myocardial infarction became the leading contributing cause of death. There was an overall decrease in the incidence of arrhythmia as the cause of death in all ages, particularly among children.

CONCLUSIONS

Patients with congenital heart disease are living longer. Arrhythmia remains the primary contributing cause of death for those with cyanotic lesions. Myocardial infarction is now the leading contributing cause for adults with noncyanotic congenital heart disease consistent with late survival and an increasing impact of acquired heart disease.

Anatomical correction of complex forms of transposition of the great arteries in neonates

OBJECTIVE

The arterial switch operation has become the procedure of choice for the simple transposition of the great arteries (TGA) while in the complex forms of the defect the staged approach is frequently implemented. The aim of this study is to compare groups of patients with simple transposition and children with the complex form of the defect and identify factors affecting early and late outcome.

DESIGN

From 1997 to 2003, 135 consecutive neonates with TGA underwent arterial switch operation and simultaneous reparation of all associated defects. Univariate and multivariate analysis of perioperative variables and follow-up data was performed. Patients were divided into two groups. Group I (n=84, 62.2%) included neonates with simple transposition (TGA/IVS), Group II (n=51, 37.8%) included children with complex transposition (TGA/VSD).

RESULTS

Overall early mortality was 8.1% and there was one late death (0.7%). One-month, 1-year and 5-year actuarial survival rates were 91.8, 91.1 and 91.1%, respectively. There were no differences in the early and late survival rate between groups. Reintervention rate for right ventricular outflow tract obstruction (RVOTO) was 13.3% (balloon plasty or reoperation). The freedom from reintervention at 1, 3 and 5 years was 98.4, 87.9 and 85.4%, respectively. There were no differences in the need for reintervention between groups. The significant differences between groups concerned: age at operation (p<0.001), associated anomalies (p=0.002) including aortic arch anomalies (p=0.002) and coronary artery anomalies (p=0.02), application of delayed chest closure (p=0.015), and occurrence of sepsis (p=0.032). Risk factors for early death were: left ventricule dysfunction related to age at operation (p=0.016) and resternotomy in intensive care unit (p<0.001). There were no differences between groups concerning these risk factors as far as circulatory arrest time, aorta clamping time, and early and late morbidity.

CONCLUSIONS

The arterial switch operation can be the treatment of choice for various forms of TGA with low early and late mortality and morbidity rates. The main cause of early death is still left ventricular dysfunction. Such well-known predictors of poor outcome as presence of ventricular septal defect, coronary artery anomalies and aortic arch anomalies did not affect early and late findings. The presented approach of early simultaneous anatomical correction of TGA and all associated anomalies ensures good condition of children with low necessity for reintervention.

Follow-up outcomes 10 years after arterial switch operation for transposition of the great arteries: comparison of cardiological health status and health-related quality of life to those of the a normal reference population

The purpose of this study was to investigate the cardiological health status and health-related quality of life after the arterial switch operation (ASO) for transposition of the great arteries (TGA) in comparison with a normative reference group. Chart review and cross-sectional systematic follow-up, including echocardiography, exercise testing, and electrocardiography, were performed on all survivors of ASO for TGA between 1990 and 1995. Health-related quality of life (HRQOL) was assessed using a standardized questionnaire. A normative reference group was included. Forty-nine survivors [median age at operation 13 days, mean age at follow-up 11 +/- 2 years (37/49 with intact ventricular septum] were identified. Thirty-three of 49 patients (67%) [22/33 TGA with intact ventricular septum (IVS)] participated in cross-sectional follow-up. Cumulative 10-year event-free survival was 88% and the re-intervention rate 6%. Aortic root dilatation occurred in 70% of patients; none had severe aortic regurgitation. Left ventricular function was normal. Exercise performance (85% of reference capacity, p = 0.02), maximal oxygen uptake (85%, p < 0.01) and peak heart rate (95%, p < 0.01) were decreased. Exercise electrocardiogram was normal as was rhythm status. Unfavourable outcomes on HRQOL were found for motor functioning and positive emotional functioning. Overall there were no significant differences between TGA/IVS and TGA/VSD. We conclude that at mid- to long-term follow-up after ASO, major events and re-interventions (6%) occur infrequently. Exercise capacity and maximal oxygen uptake are lower than those in a reference population, which could not be related to diminished ventricular function. Aortic root dilatation is frequent, irrespective of the anatomical subgroup. Severe aortic regurgitation or left ventricular dilatation was not found. The unfavourable health-related quality of life deserves further attention.

Surgically corrected congenital heart disease: utility of 64-MDCT

OBJECTIVE

The purpose of this article is to review the CT appearance of postoperative morphology and complications after surgical correction of congenital heart anomalies.

CONCLUSION

Echocardiography is typically the initial imaging technique used for congenital heart disease; however, some thoracic regions are beyond the imaging scope of echocardiography, particularly after surgical revision. This article shows, through a series of illustrative cases, the usefulness of 64-MDCT in these patients.

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.

Prediction of Early Pulmonary Artery Stenosis after Arterial Switch Operation: The Role of Intraoperative Transesophageal Echocardiography

OBJECTIVES

To investigate prospectively the prediction of the neopulmonary stenosis (neo-PS) after arterial switch operation (ASO) for transposition of the great artery (TGA) with intraoperative transesophageal echocardiography (TEE).

METHODS

Infants with TGA undergoing the ASO were prospectively studied over 5 years. The neo-PS was defined when the peak flow velocity was over 3 m/s at the neo main pulmonary artery (neo-MPA) after ASO by TEE (TEEPS). Catheterization was performed if estimated peak neo-PS pressure gradient was over 40 mm Hg by transthoracic echocardiography. Balloon angioplasty was tried first and surgical reoperation was reserved for those with failed angioplasty.

RESULTS

In total 49 consecutive patients were enrolled into the cohort study. TEEPS was identified in 21 patients. For patients with TEEPS, freedom from reintervention was 28% at 1 year and 23% at 2 years. For patients without TEEPS, freedom from reintervention for PS was 92% at 1 year and 78% at 2 years. The time interval from ASO to reintervention was significantly shorter in patients with TEEPS than without TEEPS. Existence of TEEPS and non-Lecompte method were main risk factor for reintervention.

CONCLUSION

The present study demonstrated that the application of intraoperative TEE for infants undergoing ASO is very helpful in predicting the development of early postoperative neo-PS.

Current Risk Factors and Outcomes for the Arterial Switch Operation

BACKGROUND

The arterial switch operation is the preferred treatment for dextrotransposition of the great arteries and some forms of double-outlet right ventricle.

METHODS

All patients undergoing an arterial switch operation at a single institution from January 1, 1999, to September 1, 2005, were reviewed.

RESULTS

Of the 168 patients, median age was 2 days (range, 0 to 358) and weight was 3.5 kg (range, 1.9 to 11.8 kg). Eleven patients were less than 36 weeks gestational age. Forty percent had coronary patterns other than usual. Mean cardiopulmonary bypass (CPB) time was 147 +/- 45 minutes, and mean cross-clamp time was 77 +/- 27 minutes. At a mean follow-up of 19 +/- 21 months, there were 10 (6%) hospital and 4 (3%) late deaths. Actuarial 1-month, 1-year, and 3-year survivals were 94%, 90%, and 89%, respectively. Bivariate analysis revealed weight less than 2.5 kg (p = 0.032), gestational age less than 36 weeks (p = 0.002), and CPB time greater than 150 minutes (p = 0.0075) decreased hospital survival. Intermediate-term survival was negatively impacted by weight less than 2.5 kg (p = 0.017), gestational age less than 36 weeks (p = 0.0096), CPB time greater than 150 minutes (p = 0.0050), and age at presentation greater than 4 weeks (p = 0.034). By multivariate analysis, gestational age less than 36 weeks (p = 0.0051) and CPB time greater than 150 minutes (p = 0.016) were independent risk factors for hospital mortality. Gestational age less than 36 weeks (p = 0.0096) and CPB time greater than 150 minutes (p = 0.005) were also independent predictors of intermediate-term mortality. Coronary anatomy could not be shown to affect survival, including no deaths among the 12 patients with intramural coronaries.

CONCLUSIONS

The arterial switch operation can be performed with low mortality regardless of diagnosis or coronary pattern. The premature patient and minimizing CPB time remain as challenges to optimize outcomes for the arterial switch operation.

Role and effectiveness of cardiovascular magnetic resonance in the diagnosis, preoperative evaluation and follow-up of patients with congenital heart diseases

The substantial advances in the medical and surgical treatment of congenital heart diseases have dramatically improved patients' life expectancy, as well as increased the number of those needing lifelong monitoring to identify complications and residual defects. Magnetic resonance imaging (MRI) is an ideal imaging modality for the follow-up of these young patients owing to its noninvasiveness, high reproducibility and morphological and functional accuracy. This paper describes the most appropriate MRI techniques and sequences for the study of cardiovascular heart diseases on the basis of an analysis of MRI studies carried out between January 2003 and June 2006 on 274 patients affected by all of the main congenital cardiovascular malformations, as well as a review of the literature. The advantages of MRI with respect to other imaging techniques, the problems encountered and the main clinical applications and indications of MRI, with special reference to the most common disease entities, are then discussed to define the role, the utility and the future perspectives of this imaging technique in the study of congenital heart diseases.

Antenatal diagnosis of double outlet of right ventricle without extracardiac anomaly: a report of 4 cases

Four fetuses were diagnosed antenatally with double outlet of right ventricle (DORV) at 17, 20, 26, and 28 weeks' gestation, respectively, using 2-dimensional sonography. Chromosome study was normal in all 4 cases, and there were no extracardiac abnormalities. The sonographic diagnoses were based on the following findings: (1) arising of the 2 great vessels predominantly from the right ventricle; (2) the presence of bilateral coni; and (3) parallel direction of the 2 vessels rather than the normal perpendicular course. Two cases were terminated electively with postnatal autopsy confirmation; the other 2 cases were closely monitored throughout pregnancy and underwent normal vaginal delivery at term and subsequent surgical correction with good outcome. In conclusion, DORV can be readily diagnosed in utero by checking outflow tract even without 3-dimensional sonography and in the absence of obvious risk for congenital heart defects.

Coronary reimplantation after neoaortic reconstruction can yield better result in arterial switch operation: comparison with open trap door technique

BACKGROUND

Accurate coronary reimplantation is the most important component in the arterial switch operation. It is especially demanding for the less experienced surgeons. We compared the result of the technique of coronary reimplantation after neoaortic reconstruction with that of the open trap door technique.

METHODS

From March 1994 to June 2004, 103 consecutive patients underwent the arterial switch operation by one surgeon. Patients who underwent coronary artery transfer with other modified techniques were excluded. Diagnoses of 94 patients were transposition of the great arteries with intact ventricular septum (n = 50), transposition of the great arteries with ventricular septal defect (n = 26), and the Taussig-Bing anomaly (n = 18). An aortic arch anomaly was present in 13 patients. The median age of the patients was 12 days and the mean body weight was 3.5 kg. Coronary reimplantation after neoaortic reconstruction was applied to 34 patients (group I), and the open trap door technique was applied to the rest (group II).

RESULTS

Preoperative data were similar in both groups. Four patients in group II required intraoperative revision of a transferred coronary artery, and 1 patient with an intramural left coronary artery in group I had a conversion to free grafting using the left subclavian artery. Overall early mortality was 17.0% (16 of 94). Mortality in group I (1 of 34; 2.9%) was significantly lower than in group II (15 of 60; 25.0%) (p = 0.008). The leading cause of death in group II was low cardiac output (n = 9). During the follow-up, an aortic regurgitation of greater than mild was detected in 2 patients in group II.

CONCLUSIONS

Coronary reimplantation after neoaoartic reconstruction is an attractive method to minimize coronary artery transfer-related mortality or morbidity.

Prevalence of arrhythmias and their risk factors mid- and long-term after the arterial switch operation

Early results of the arterial switch operation (ASO) for transposition of the great arteries (TGA) are good, but there are few mid- and long-term data on postoperative arrhythmias, especially in Japan. In this study, clinical data on 624 1-year survivors who had an ASO between 1976 and 1995 were collected from six institutes in Japan up to October 2002. Sixty (9.6%) 1-year survivors had significant arrhythmias. Bradycardia occurred in 22 patients, including complete atrioventricular block (CAVB) in 12, sick sinus syndrome (SSS) in 6, and second-degree atrioventricular block in 4. Syncope developed in 2 with CAVB and 2 with SSS. Ten patients with bradycardia underwent permanent pacemaker implantation. Supraveutricular tachycardia (SVT) was seen in 25 patients, including paroxysmal supraventricular tachycardia in 16, atrial flutter in 7, and atrial fibrillation in 2. Six patients with SVT received antiarrhythmic medication. SVT was transient in 20 and persistent in 5. Ventricular arrhythmias occurred in 13 patients, including nonsustained ventricular tachycardia in 5, paroxysmal ventricular contractions with couplets in 5, ventricular flutter in 2, and sustained ventricular tachycardia in 1. Four patients with ventricular arrhythmias received antiarrhythmic medication. Of the study patients, 8 died 1 year or more after ASO. Death was directly related to arrhythmia in 1 patient and was due to nonsustained ventricular tachycardia with severe congestive heart failure. The presence of a ventricular septal defect (VSD) was a risk factor for postoperative arrhythmia. Patients with TGA and VSD had more arrhythmias than those with TGA and an intact ventricular septum (13.7 vs 8.7%, p < 0.05), and this was especially true for CAVB (3.9% vs 1.0%, p < 0.05). In 36 patients clearly documented time onset of postoperative arrhythmia arrhythmia developed in 18 (50%) after less than 1 year and in 15 (42%) after more than 5 years. In summary serious arrhythmias after ASO were uncommon, but postoperative arrhythmias, such as unpaced CAVB, SSS, and VT, were related to morbidity and mortality. VSD was a risk factor for postoperative arrhythmia, especially CAVB. Approximately half of the arrhythmias developed late. Lifelong monitoring with respect to arrhythmia is needed for patients after ASO.

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.

Is the arterial switch operation as good over the long term as we thought it would be?

Surgical intervention for hearts with transposition, defined as concordant atrioventricular and discordant ventriculo-arterial connections, has been one of the landmark achievements in the field of paediatric cardiac surgery. In the early 1950s, pioneer surgeons attempted to palliate patients with transposed arterial trunks with an early form of the arterial switch operation. As a result of initially dismal outcomes secondary to difficulties with coronary arterial transfer, the unprepared nature of the morphologically left ventricle, and primitive methods for cardiopulmonary bypass, the arterial switch was abandoned in favour of several procedures achieving correction at atrial and venous levels, culminating in the Mustard and Senning operations.1,2These innovative procedures produced the earliest surviving children with transposition. Although the atrial switch procedures achieved widespread acceptance and success during the mid-1960s through the mid-1980s, the search for an operation to return the great arteries to their normal anatomic positions continued. This pursuit was stimulated primarily by the accumulating observations in mid-to-late term follow up studies of: an increasing frequency of important arrhythmic complications, including sinus nodal dysfunction, atrial arrhythmias, and sudden, unexplained death, by the development of late right ventricular dysfunction and significant tricuspid regurgitation in a ventricle potentially unsuited for a lifetime of systemic function by a small but important prevalence of obstruction of the systemic and/or pulmonary venous pathways, and by dissatisfaction with the operative mortality in the subgroup of infants complicated by additional presence of a large ventricular septal defect.3–6As we have already discussed, a number of novel procedures to achieve anatomic correction had been described as early as 1954, but clinical success was not accomplished until 1975, when Jatene and co-workers7astounded the world of paediatric cardiology with their initial description.

The arterial switch operation in Europe for transposition of the great arteries: a multi-institutional study from the European Congenital Heart Surgeons Association

OBJECTIVES

This study analyzes the results of the arterial switch operation for transposition of the great arteries in member institutions of the European Congenital Heart Surgeons Association.

METHODS

The records of 613 patients who underwent primary arterial switch operations in each of 19 participating institutions in the period from January 1998 through December 2000 were reviewed retrospectively.

RESULTS

A ventricular septal defect was present in 186 (30%) patients. Coronary anatomy was type A in 69% of the patients, and aortic arch pathology was present in 20% of patients with ventricular septal defect. Rashkind septostomy was performed in 75% of the patients, and 69% received prostaglandin. There were 37 hospital deaths (operative mortality, 6%), 13 (3%) for patients with an intact ventricular septum and 24 (13%) for those with a ventricular septal defect (P < .001). In 36% delayed sternal closure was performed, 8% required peritoneal dialysis, and 2% required mechanical circulatory support. Median ventilation time was 58 hours, and intensive care and hospital stay were 6 and 14 days, respectively. Although of various preoperative risk factors the presence of a ventricular septal defect, arch pathology, and coronary anomalies were univariate predictors of operative mortality, only the presence of a ventricular septal defect approached statistical significance (P = .06) on multivariable analysis. Of various operative parameters, aortic crossclamp time and delayed sternal closure were also univariate predictors; however, only the latter was an independent statistically significant predictor of death.

CONCLUSIONS

Results of the procedure in European centers are compatible with those in the literature. The presence of a ventricular septal defect is the clinically most important preoperative risk factor for operative death, approaching statistical significance on multivariable analysis.

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.

Arterial switch operation using aortic homograft for transposition of the great arteries with pulmonary regurgitation

We report a case of a 15 month-old boy who underwent the arterial switch operation using cryopreserved aortic homograft for transposition of the great arteries with pulmonary regurgitation, with coexisting right ventricular outflow tract obstruction precluding atrial switch operation. Follow-up echocardiography at 6 months showed trivial neoaortic valve regurgitation, no significant systemic outflow obstruction, with good cardiac function. In small children, the choice of material for left ventricular outflow tract reconstruction is one of the most crucial issues. Cryopreserved homograft has been one of the primary options for the aortic valve replacement in small children because of the ease of suturing and excellent hemostasis.

Late Results After PTCA for Coronary Stenosis After the Arterial Switch Procedure for Transposition of the Great Arteries

BACKGROUND

The arterial switch operation has become the surgical approach of choice for d-transposition of the great arteries, but there is an increased awareness of adverse sequelae in some survivors. Long-term patency and normal function of the translocated coronary arteries must be achieved. It is reported that dependent of the prior coronary status, 3% to 11% of all survivors have proximal coronary stenosis or complete occlusion develop after arterial switch operations. However, treatment of these stenoses is still a matter of debate. Late results after percutaneous transluminal coronary angioplasty (PTCA) for coronary stenosis after the arterial switch operation for d-transposition of the great arteries are reported.

METHODS

Seven children after arterial switch operation for d-transposition of the great arteries who had subsequently undergone PTCA for coronary stenosis were angiographically re-evaluated 3 to 15 months after the initial PTCA and again after 3 to 5 years.

RESULTS

All children survived the initial PTCA procedure. There were no late deaths. The degree of stenosis before PTCA ranged from 74% to 97%; immediately after PTCA from 5% to 10%; at 3 to 15 months after PTCA from zero to 6%; and at 3 to 5 years after PTCA from zero to 3%. Three to 5 years after PTCA all children showed normal development of the treated coronary artery.

CONCLUSIONS

Primary PTCA of stenotic proximal coronary arteries after the arterial switch procedure for d-transposition of the great arteries seems to be an effective treatment with excellent long-term results.

Konno procedure using atrioventricular groove patch plasty after arterial switch operation

A patient with transposition of the great arteries accompanied by Shaher type 9 coronary anatomy experienced the development of progressive neoaortic valvular regurgitation with a small annulus, supravalvular stenosis, and neopulmonary valvular and supravalvular stenoses 15 years after an arterial switch operation. To implant a prosthetic valve clinically adequate in size, the Konno procedure was necessary. However, the right coronary anatomy precluded the original Konno procedure. My colleagues and I accomplished neoaortic anterior annular enlargement in this case by using atrioventricular groove patch plasty without jeopardizing the right coronary artery, and this resulted in a satisfactory outcome.

Late outcomes in patients with surgically treated congenital heart disease

Optimizing late outcomes should be the end result of improvements in medical and surgical care for congenital heart disease (CHD). In addition to mortality, significant morbidities after surgery for CHD need to be considered. These include the need for reintervention, cardiovascular complications, exercise limitations, neurocognitive morbidities, effects on pregnancy, difficulty obtaining insurance, need for chronic medications, and impaired functional status and quality of life. Long-term outcome studies are difficult to perform, and their interpretation is complicated by intervening changes in management. Specific discussion of long-term follow-up of tetralogy of Fallot, D-transposition of the great arteries, and hypoplastic left heart syndrome illustrates the myriad management changes over the last three decades, the challenges in predicting outcomes for recent patients, and the need for ongoing initiation of long-term follow-up studies.

Sudden death in congenital heart disease

Sudden cardiac death is a common mechanism of demise in association with congenital cardiac abnormalities. The varied mechanisms may include failure of the transitional circulation, arrhythmias, postoperative or perioperative complications in the neonate and coronary ischaemia, arrhythmias, sepsis, thrombosis, or pulmonary hypertensive crisis in the older child. Knowledge of the natural history of unoperated and operated forms of congenital heart disease and long term follow up with the detection and treatment of underlying hemodynamic abnormalities should improve outcomes. There are few patients with congenital cardiac anomalies that are cured and most require long term care.

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.

Cardiovascular response to physical exercise in adult patients after atrial correction for transposition of the great arteries assessed with magnetic resonance imaging

OBJECTIVE

To assess with magnetic resonance imaging (MRI) cardiovascular function in response to exercise in patients after atrial correction of transposition of the great arteries (TGA).

METHODS

Cardiac function at rest and during submaximal exercise was assessed with MRI in 27 patients with TGA (mean (SD) age 26 (5) years) late (23 (2) years) after atrial correction and in 14 control participants (25 (5) years old).

RESULTS

At rest, only right ventricular ejection fraction was significantly lower in patients than in controls (56 (7)% v 65 (7)%, p < 0.05). In response to exercise, increases in right ventricular end diastolic (155 (55) ml to 163 (57) ml, p < 0.05) and right ventricular end systolic volumes (70 (34) ml to 75 (36) ml, p < 0.05) were observed in patients. Furthermore, right and left ventricular stroke volumes and ejection fraction did not increase significantly in patients. Changes in right ventricular ejection fraction with exercise correlated with diminished exercise capacity (r = 0.43, p < 0.05).

CONCLUSIONS

In patients with atrially corrected TGA, MRI showed an abnormal response to exercise of both systemic right and left ventricles. Exercise MRI provides a tool for close monitoring of cardiovascular function in these patients, who are at risk for late death.

Results of arterial switch operation for primary total correction of the Taussig-Bing anomaly

BACKGROUND

This study evaluates the results of the arterial switch operation for early total repair of double-outlet right ventricle with subpulmonary ventricular septal defect (the Taussig-Bing heart).

METHODS

From 1986 through April 2003, 27 patients with Taussig-Bing anomaly underwent arterial switch operation. Twenty patients were neonates (n = 11) or infants younger than 3 months (n = 9). Obstruction of aortic arch (n = 19) or subaortic right ventricular outflow tract obstruction (n = 20) and unusual coronary artery patterns (n = 19) were common. Total correction as a single procedure was performed in 21 patients. Events are depicted by Kaplan-Meier curves.

RESULTS

There was 1 patient hospital death at 2 months after repair. One patient died late that was not cardiac related. Survival was 92% +/- 6% at 8 months and remained constant thereafter. Four patients underwent reoperation (1 for residual aortic arch obstruction and 3 for subvalvular and valvular pulmonary stenosis). Freedom from reoperation decreased to stabilize at 83% +/- 8% after 2 years. The risk to have right ventricular outflow tract obstruction develop was 33% +/- 10% at 1 year, increasing slowly and leveling out at 57% +/- 12% at year 5 and thereafter. Statistical analysis revealed no significant risk factor for death or need for reoperation.

CONCLUSIONS

The Taussig-Bing anomaly should be corrected in the neonatal period or in early infancy by arterial switch operation, closure of the ventricular septal defect, and simultaneous correction of associated cardiovascular anomalies as a one-stage procedure. Right ventricular outflow tract obstruction often complicates the postoperative course and is the main cause for reintervention.

Prevalence and predictors of neoaortic regurgitation after arterial switch operation for transposition of the great arteries

BACKGROUND

The fate of the native pulmonary valve after arterial switch operation is still unknown and may become a cause for a secondary aortic valve operation during adult life. We evaluated the prevalence and predictive factors associated with neoaortic valvular regurgitation by a retrospective study of children who underwent arterial switch operation for transposition of the great arteries.

METHODS

The onset of neoaortic valvular regurgitation was correlated with demographic data, cardiac anatomy, surgical technique, and postoperative ventricular function. The size of the neoaortic root and ascending aorta was measured in a selected subset of patients.

RESULTS

Among 253 survivors, 173 were eligible for the study. After a median follow-up time of 8.2 years, 61 patients showed echocardiographic or angiographic evidence of valvular incompetence, which was progressive in 14 cases; this led to surgical intervention in 2 patients, and there was 1 operative death. At multivariate analysis, the onset of valvular regurgitation was correlated with the trap-door technique for coronary reimplantation (P <.01). A smooth transition from the aortic sinus to the ascending aorta, with loss of the normal sinotubular junction geometry, may be associated with valvular incompetence.

CONCLUSIONS

After arterial switch operation, there is an increasing frequency of neoaortic regurgitation, which may lead to significant valvular dysfunction later in life. The trap-door type of coronary reimplantation is associated with an increased risk for valvular dysfunction, possibly because of a distortion of the sinotubular junction geometry. For this reason, we recommend the punch technique for repair in all but the most complicated coronary pattern.

Clinical update on adults with congenital heart disease

The number of patients with congenital cardiac disease reaching adulthood is increasing steadily. Many adults with such disease face both medical and surgical difficulties. Most clinicians know very little about basic cardiac defects, their natural history, complications after surgery, and adequate management of these patients. We aim to provide an overview of the most frequently encountered cardiac lesions and long-term complications and to outline an up-to-date approach to their management. We present a series of hypothetical cases and discuss their management.