Stent expansion of restrictive Fontan conduits to nominal diameter and beyond.

BACKGROUND: Mechanical factors may cause bottlenecks in a Fontan circuit. Extracardiac conduits (ECC) are placed at a young age, but the materials do not allow growth. Restriction in ECC dimensions may deteriorate the function of the circuit. AIMS: This study aimed to evaluate the feasibility and safety of stent expansion of an ECC to the nominal dimension at the time of implant and, if possible, beyond nominal. METHODS: Retrospective, single-center observational review of all ECC Fontan patients who received a stent to expand a previously placed surgical conduit. RESULTS: A total of 44 restrictive conduits were stented over a 14-year study period with a median of 11.8 (interquartile ranges [IQR]: 9.1-13.8) years after ECC placement. Cross-sectional areas were a median of 30% (IQR: 21-42) smaller than the originally placed ECC; there was no gradient in 23/44 patients and in 21/44, a minimal gradient of 1.3 ± 0.5 (range 1-3 mmHg). All conduits could be enlarged with a significant (p < 0.0001) increase in diameter from 13.6 ± 1.8 to 19.2 ± 1.2 mm, corresponding to a median cross-sectional area increase of 171% (IQR: 153-220). In three patients where the conduits were not contracted, expansion of between 127% and 165% was obtained. There were no conduit ruptures and only one minor complication. CONCLUSIONS: ECC in some Fontan patients become smaller than nominal over time, usually without overt symptoms. The dimensions of ECC's can be safely and significantly increased to nominal or even beyond employing stenting. It allows adjustment of ECC dimensions to compensate for somatic growth.

Can ductus arteriosus morphology influence technique/outcome of stent treatment?

INTRODUCTION: Results and outcomes of ductus arteriosus stenting vary widely. The aim of this study was to determine whether ductus morphology is associated with different procedural outcome. METHODS: Over an 18-year period, 123 patients presented with ductal dependent pulmonary blood flow. Results were retrospectively assessed based on radiographic anatomic features of the ductus arteriosus: Group 1: "straight" ductus arteriosus, typically seen in patients with Pulmonary atresia with intact septum (PA-IVS), Group 2: "intermediate" ductus arteriosus as seen in severe pulmonary stenosis (PS)-single ventricle, Group 3: "vertical" ductus arteriosus typically seen in patients with pulmonary atresia-ventricular septal defect, Group 4: ductus arteriosus arising from the aorta to a single lung, Group 5: ductus arteriosus arising from the innominate/subclavian artery to a single lung, Group 6: ductus arteriosus from innominate/subclavian artery to both lungs. RESULTS: Ductal stenting (DS) was attempted in 98 patients with 99 ducts. Successful stenting was possible in 83 patients. Success of DS was significantly different among the groups (p = .04, F = 5.41). Groups 1, 4, and 5 were "easy" with good success while Groups 2, 3, and 6 were complex and demanding. There were two deaths (after 5 and 7 days, respectively) that could be ascribed to DS. Elective re-interventions were performed in 34 ductuses (40%). Fifty three percent (n = 44/83) of successful ductus stents proceeded to further surgery and 20 ducts closed spontaneously in asymptomatic patients over time. CONCLUSIONS: Ductus arteriosus morphology influences technique and determines complexity, safety, and final outcome of ductus arteriosus stenting.

Perioperative Risk Factors for Mortality in Patients Undergoing Surgery for Ebstein's Anomaly at a Single Institution: A Retrospective Analysis.

BACKGROUND: Mortality after cardiac surgery for Ebstein's anomaly ranges from 2.5% to 31%. Independent predictors for mortality and morbidity remain poorly defined because of the low incidence of this congenital anomaly. To identify potentially modifiable factors, this retrospective study investigates the prognostic value of perioperative variables for mortality and morbidity. METHODS: We reviewed the charts of 171 patients with Ebstein's anomaly who were at one point in follow-up at our center. Only patients who underwent cardiac surgery for this anomaly were included. The primary endpoint was a composite of mortality or rehospitalization for cardiac reasons within 1 year of surgery. Logistic regression and Cox regression models were used to study the predictive value of various variables. RESULTS: We identified 32 patients (median age 12 years; range 7 days to 70 years) who underwent a total of 49 surgical procedures for Ebstein's anomaly at our institution between November 1987 and March 2015. The following variables were significantly associated with the primary outcome: increased severity of tricuspid valve stenosis (odds ratio 2.089; 95% confidence interval 1.175 to 3.713) and right ventricular dysfunction (1.826; 1.109 to 3.006), partial corrective surgery (versus corrective surgery) (6.709; 1.436 to 31.344), occurrence of major postoperative complications (5.460; 1.419 to 21.008), and increased length of stay in the intensive care unit (1.051; 1.010 to 1.093). A better outcome was observed with the use of intraoperative cardioplegic arrest (0.185; 0.063 to 0.550), atrial septal defect closure during surgery, and longer duration of surgery (0.991; 0.984 to 0.998). CONCLUSION: Several patient-specific characteristics and perioperative characteristics were associated with a poorer outcome after cardiac surgery for Ebstein's anomaly. The outcome seems to be primarily determined by the severity of the valve dysfunction and right ventricular performance, with only a minor role for perioperative surgical or anesthetic technical determinants.

Critical Coarctation of the Aorta in Selective Fetal Growth Restriction and the Role of Coronary Stent Implantation.

INTRODUCTION: Monochorionic twins are at increased risk of congenital heart defects (CHDs). Up to 26% have a birth weight <1,500 g, a CHD requiring neonatal surgery, therefore, poses particular challenges. OBJECTIVE: The aim of the study was to describe pregnancy characteristics, perinatal management, and outcome of monochorionic twins diagnosed with critical coarctation of the aorta (CoA). METHODS: We included monochorionic twins diagnosed with critical CoA (2010-2019) at 2 tertiary referral centers, and we systematically reviewed the literature regarding CoA in monochorionic twins. RESULTS: Seven neonates were included. All were the smaller twin of pregnancies complicated by selective fetal growth restriction. The median gestational age at birth was 32 weeks (28-34). Birth weight of affected twins ranged as 670-1,800 g. One neonate underwent coarctectomy at the age of 1 month (2,330 g). Six underwent stent implantation, performed between day 8 and 40, followed by definitive coarctectomy between 4 and 9 months in 4. All 7 developed normally, except for 1 child with neurodevelopmental delay. Three co-twins had pulmonary stenosis, of whom 1 required balloon valvuloplasty. The literature review revealed 10 cases of CoA, all in the smaller twin. Six cases detected in the first weeks after birth were treated with prostaglandins alone, by repeated transcatheter angioplasty or by surgical repair, with good outcome in 2 out of 6. CONCLUSIONS: CoA specifically affects the smaller twin of growth discordant monochorionic twin pairs. Stent implantation is a feasible bridging therapy to surgery in these low birth weight neonates.

Percutaneous obliteration of the right ventricle to avoid coronary damage by sinusoids in patients with pulmonary atresia intact ventricular septum during staged single ventricle palliation.

BACKGROUND AND AIMS: Suprasystemic pressure waves can damage the coronary arteries resulting in myocardial ischemia and excess early mortality. We aimed to reduce the coronary pressure wave through the sinusoids by abolishing RV volume with percutaneous devices. METHODS AND RESULTS: Four patients with PA-IVS and coronary sinusoids from the hypertensive rudimentary RV were evaluated at a median age 26.6 months (range: 2.7-51.7). Right ventricle coronary dependent flow to the left ventricular myocardium was excluded. All four patients had dual perfusion with competitive flow from the RV through the sinusoids to the coronary arteries. Devices used were: Amplatzer vascular plug II of 10-16 mm; 27 coils (diameter 5-15 mm) in the oldest patient. Right ventricular angiography after cavity obliteration showed no more significant coronary perfusion through the sinusoids. There were no complications or deaths. Only minor and transient changes in the levels of troponin were observed. Coronary angiography at pre-Fontan evaluation showed no progress of coronary abnormalities in two patients. CONCLUSION: In selected patients with functionally single left ventricle, obliteration of the hypertensive RV cavity by percutaneous devices is safe and abolishes the systolic pressure wave in coronary sinusoids. When performed early, this may halt coronary damage and avoid excess mortality.

Radiofrequency perforation of the pulmonary valve: an efficient low cost solution.

Objective The aim of the study was to assess the feasibility of using commonly available catheterization laboratory equipment for radiofrequency perforation of the pulmonary valve in patients with pulmonary atresia and intact ventricular septum. Methods The system (off-label use for all items) is made up of a co-axial telescopic arrangement consisting of a 0.014" PT 2 ™ coronary guidewire, for insulation inside a 2.7-F microcatheter which has an inner lumen of 0.021". The microcatheter was passed via a standard 4-F right coronary catheter to just below the atretic pulmonary valve. Radiofrequency (RF) energy was delivered using a standard electrosurgical system. In vitro testing had been performed and indicated that 5-10 W for 2-5 s would be sufficient for valve perforation. Results Radiofrequency perforation was successfully performed in all (n = 5, 100%) patients at a median age of 3 days (range: 1-36) and weight 2.7 kg (range 2.3-3.0). In one patient the pericardium was entered during the initial attempt; the generator was put on coagulation mode during retrieval of the guidewire and no haemopericardium occurred. The pulmonary valve was dilated in all; in three patients (n = 3) the ductus arteriosus was stented during the same session. Conclusion Results of the study show that it is feasible to perforate the pulmonary valve safely using this system. Availability, simplicity and cost are noteworthy benefits.

Dysfunction of the foetal arterial duct results in a wide spectrum of cardiovascular pathology.

OBJECTIVE: Foetal ductal problems may have various cardiopulmonary consequences. This study aimed to identify the spectrum of ductus arteriosus (DA) dysfunction (closure, constriction, kinking, aneurysm and thrombosis) and the resultant clinical and echocardiographic presentation in foetuses and neonates. METHODS AND RESULTS: This is a retrospective analysis of serial pre- and post-natal data of 27 cases of foetal ductal dysfunction diagnosed at a median gestational age of 33 weeks (range 20-39). The most common abnormalities observed were premature closure of the DA in 56% (15/27) and constriction in 29% (8/27). Right ventricular hypertrophy was present in 75% (n = 11/15) of foetuses with premature DA closure, while ventricular dilation (4/7, 57%) was a more common feature in foetuses with ductal constriction. After birth, 63% (17/27) of new borns presented with cyanosis and pulmonary hypertension that required active treatment. Three infants died after birth. Abnormalities resolved spontaneously after birth in about 50% of patients. In some children, pulmonary valve stenosis and regurgitation was progressive and required further treatment. CONCLUSIONS: An abnormal right heart on foetal four-chamber ultrasound view should alert the sonographer to the possible presence of foetal ductal dysfunction. Ductal occlusion, transient or fixed constriction, kinking and aneurysm formation are associated with foetal cardiopulmonary sequelae. Symptoms and pathology is probably related to the type, foetal age, rapidity of progression and duration of intrauterine ductal dysfunction. Correspondingly, clinical outcomes vary ranging from little or no symptoms to severe respiratory distress and even foetal or neonatal death.

Percutaneous intervention for central shunts: new routes, new strategies.

Introduction In traditional locations, the standard Blalock-Taussig shunt presents numerous technical difficulties for percutaneous intervention. We changed our strategy to a central type shunt (Laks-type) with end-to-side pulmonary and side-to-side aortic anastomosis. The aim of this study was to determine whether this modified strategy would allow easier percutaneous manipulation in patients with small pulmonary arteries. Methods All children with a stretchable central vascular graft who required any form of percutaneous intervention were prospectively enrolled in the study. Results Eleven infants were evaluated a median time of 3 months (range 0.9-4.4) following initial shunt placement; the median weight at intervention was 5.7 kg (range: 4.0 - 10.0). All shunts (100%) were easily and swiftly entered without the need for special catheters or co-axial systems. In four patients other interventions in distal pulmonary arteries were first performed: cutting balloon treatment in three and balloon angioplasty of peripheral pulmonary artery stenosis in one. The shunts were then augmented with a stent with a diameter increasing from 3.5 ± 0.4 mm to 4.7 ± 0.8 mm and saturation increasing from 76% (range: 69-88) to 84% (range: 77-88) (P < 0.05). Several months later, two children required further interventions that could easily be performed via the stented shunts. No complications were observed. Conclusions The Laks-type shunt provides easy access for percutaneous procedures of the distal pulmonary arteries including cutting balloons; this shunt can predictably be expanded to augment pulmonary flow. This study highlights how co-operation between the interventionalist and the surgeon can improve strategies to manage these difficult patients.

Mitral valve replacement in children: balancing durability and risk with mechanical and bioprosthetic valves.

OBJECTIVES: To investigate if there is still a place for bioprosthetic mitral valve replacement in children by comparing the prosthetic durability and transplant-free survival after bioprosthetic and mechanical mitral valve replacement. METHODS: We reviewed all mitral valve replacements in children between 1981 and 2020. Bioprosthetic mitral valve replacement cases were individually matched to mechanical mitral valve replacement cases. The incidence rate of a 2nd replacement was calculated using the cumulative incidence function that considered death or transplantation as a competing risk. RESULTS: The median age at implantation was 3.6 years (interquartile range 0.8-7.9) for the bioprosthetic valve cohort (n = 28) and 3 years (interquartile range 1.3-7.8) for the mechanical valve cohort (n = 28). Seven years after bioprosthetic mitral valve replacement, the cumulative incidence of death or transplantation was 17.9% [95% confidence interval (CI) 6.3-34.1] and the cumulative incidence of a 2nd replacement was 63.6% (95% CI 39.9-80.1). Seven years after mechanical mitral valve replacement, the cumulative incidence of death or transplantation was 28.6% (95% CI 13.3-46) and the cumulative incidence of a 2nd replacement was 10.7% (95% CI 2.6-25.5). Fifteen years after mechanical mitral valve replacement, the cumulative incidence of death or transplantation was 33.6% (95% CI 16.2-52.1) and the cumulative incidence of a 2nd replacement was 41.1% (95% CI 18.4-62.7). The cumulative incidence curves for bioprosthetic and mechanical mitral valve replacement were statistically different for a 2nd valve replacement (P < 0.001) but not for death or transplantation (P = 0.33). CONCLUSIONS: There is no difference in transplant-free survival after bioprosthetic and mechanical mitral valve replacement in children. The lifespan of bioprosthetic mitral valves remains limited in children because of structural valve failure due to calcification. After 15 years, 40% of mechanical valves were replaced, primarily because of patient-prosthesis mismatch related to somatic growth.

Mechanism of autograft insufficiency after the Ross operation in children.

BACKGROUND: It is unclear how autografts grow and dilate after the Ross operation in children. We analysed autograft growth and dilatation in children who underwent the Ross operation and examined the relationship of these factors to autograft failure. METHODS: From our institutional database, we retrospectively identified 33 children who underwent the Ross operation without aortic root reinforcement (mean age 9.9 years) and had normal body measurements and echocardiographic data throughout follow-up. RESULTS: Autograft insufficiency developed in 10 patients 5.1 years after the Ross operation. The average Z score at the development of autograft insufficiency was -0.1 (range from -2.0 to 6.1). The proportions of patients who remained free of autograft insufficiency at 5 and 10 years were 87.2% and 55.7%, respectively. A consistent trend in the time course of Z score was not found in any age group studied. CONCLUSIONS: Autograft growth and dilation after the Ross operation varied widely among patients, and the incidence of autograft insufficiency was independent of annulus size.

Left atrial strain in patients after arterial switch operation for transposition of the great arteries.

BACKGROUND: Left atrial (LA) strain, comprising LA reservoir, conduit and contractile function could add mechanistic information of patients after arterial switch operation (ASO) for transposition of the great arteries (TGA). ASO patients might have abnormal ventriculoarterial coupling, which makes them vulnerable to left ventricle (LV) dysfunction and results in reduced exercise capacity. This explorative study aimed to evaluate the relation between LA strain, atrial size, ventricular function, and exercise data obtained by cardiopulmonary exercise testing (CPET). METHODS: In a cohort of 44 patients (71% male, mean age 25 ± 4 years) LA strain was measured using transthoracic speckle-tracking echocardiography. Further assessment involved standard echocardiography, CPET evaluation, and blood sampling. LA strain values were compared to normal values. Correlations were calculated. Regression analysis with all strain variables to the CPET data was performed. RESULTS: LA reservoir, conduit and contractile strain were normal in 30%, 89% and 50% of the patients, respectively. LA reservoir/contractile strain correlated to LV ejection fraction (ρ 0.310/-0.159, respectively) and LA reservoir/conduit strain correlated to the LA volume index (ρ 0.336/-0.357, respectively). None of the individual LA strain parameters were associated with the CPET variables. In multivariate regression analysis, LA contractile strain was significantly associated with the percentage of predicted maximal heart rate (ß - 2.555). CONCLUSIONS: These data suggest that in TGA patients after ASO repair LA strain is impaired and correlates with LA size and LV function. However, impaired LA strain wasn't associated with the standard CPET parameters. As such, clinical significance needs to be further unravelled.

Evolution of the Z-score in size-reduced bicuspid homografts.

BACKGROUND AND AIM OF THE STUDY: Human homografts are frequently used to establish an anatomic continuity between the right ventricular outflow tract (RVOT) and the pulmonary artery. Their limited availability, especially in small sizes, has encouraged the use of alternative strategies, such as size-reduced bicuspid homografts. The study aim was to analyze the follow up of patients who had received a standard tricuspid or size-reduced bicuspid homograft in the RVOT position, and to investigate modifications of the patients' Z-scores over the years. METHODS: A consecutive series of 107 patients aged < or = 16 years, who underwent RVOT repair between 1989 and 2010 to treat tetralogy of Fallot (ToF), was retrospectively reviewed. Of these patients, 17 received a size-reduced bicuspid pulmonary homograft, while 90 received a standard tricuspid homograft. The mean follow up periods were 10.5 years (range: 0.02-21.4 years) for the whole study population, and 11.8 years and 3.4 years, respectively, for the tricuspid and size-reduced bicuspid homograft groups. RESULTS: Freedom from mortality at 10 years was 95 +/- 3%. During the observation period, 27 patients (31%) in the tricuspid homograft group and two (125) in the size-reduced bicuspid group presented with graft failure. According to the multivariable analysis, the only independent predictor of graft failure was patient age (hazards ratio 0.86). The 17 patients who had received a size-reduced bicuspid homograft were then age-matched to an equal-sized population of tricuspid homograft patients. A comparative analysis of the time-weighted average of the Z-scores for these tricuspid and size-reduced bicuspid homograft subgroups during the follow up period failed to identify any statistical difference (p = 0.5). CONCLUSION: In terms of Z-score evolution, size-reduced bicuspid homografts offer results which are comparable to those achieved with tricuspid homografts.

Treatment strategies for pulmonary sequestration in childhood: resection, embolization, observation?

BACKGROUND: The ideal treatment strategy for pulmonary sequestration whether resection or embolization in childhood is not clearly defined. Our institution has no clear policy, therefore both therapies are performed. OBJECTIVE: The aim of this study was to assess local management strategies of children presenting with pulmonary sequestrations. METHODS: This is a retrospective, single-institutional review. The main inclusion criterion was the established diagnosis of a pulmonary sequestration. Forty-eight patients were divided into three groups based on treatment received: conservative management (n = 5), surgery (n = 22) and embolization (n = 21). RESULTS: The median age at treatment was 8.0 months (range 1.2- 166.0) in the surgical, 4.0 months (range 0.2 - 166.0) in the embolization and 8 months (range 0.3 - 197.0) in the conservatively managed groups, respectively. Age at treatment was similar in the surgical and embolization groups (P = 0.9). Recurrent chest infections were the most common clinical presentation in the surgical group, whilst cardiac failure was the most frequent symptom in the embolization group (P < 0.01; 95% CI: 0.3 to 0.9). There were six complications in the surgical group and one in the embolization group (P = 0.1). In one patient embolization was not possible. Outcomes in both groups were comparable with good results on follow-up. CONCLUSION: Both surgery and endovascular embolization are effective and safe treatments for pulmonary sequestration. The presenting symptoms dictate therapy: surgery if there is infection and embolization if a shunt needs to be abolished. Our institutional policy remains unchanged.

Neurocognitive development of children 4 years after critical illness and treatment with tight glucose control: a randomized controlled trial.

CONTEXT: A large randomized controlled trial revealed that tight glucose control (TGC) to age-adjusted normoglycemia (50-80 mg/dL at age <1 year and 70-100 mg/dL at age 1-16 years) reduced intensive care morbidity and mortality compared with usual care (UC), but increased hypoglycemia (≤40 mg/dL) (25% vs 1%). OBJECTIVE: As both hyperglycemia and hypoglycemia may adversely affect the developing brain, long-term follow-up was required to exclude harm and validate short-term benefits of TGC. DESIGN, SETTING, AND PATIENTS: A prospective, randomized controlled trial of 700 patients aged 16 years or younger who were admitted to the pediatric intensive care unit (ICU) of the University Hospitals in Leuven, Belgium, between October 2004 and December 2007. Follow-up was scheduled after 3 years with infants assessed at 4 years old between August 2008 and January 2012. Assessment was performed blinded for treatment allocation, in-hospital (83%) or at home/school (17%). For comparison, 216 healthy siblings and unrelated children were tested. MAIN OUTCOME MEASURES: Intelligence (full-scale intelligence quotient [IQ]), as assessed with age-adjusted tests (Wechsler IQ scales). Further neurodevelopmental testing encompassed tests for visual-motor integration (Beery-Buktenica Developmental Test of Visual-Motor Integration); attention, motor coordination, and executive functions (Amsterdam Neuropsychological Tasks); memory (Children's Memory Scale); and behavior (Child Behavior Checklist). RESULTS: Sixteen percent of patients declined participation or could not be reached (n = 113), resulting in 569 patients being alive and testable at follow-up. At a median (interquartile range [IQR]) of 3.9 (3.8-4.1) years after randomization, TGC in the ICU did not affect full-scale IQ score (median [IQR], 88.0 [74.0-100.0] vs 88.5 [74.3-99.0] for UC; P = .73) and had not increased incidence of poor outcomes (death or severe disability precluding neurocognitive testing: 19% [68/349] vs 18% [63/351] with UC; risk-adjusted odds ratio, 0.93; 95% CI, 0.60-1.46; P = .72). Other scores for intelligence, visual-motor integration, and memory also did not differ between groups. Tight glucose control improved motor coordination (9% [95% CI, 0%-18%] to 20% [95% CI, 5%-35%] better, all P ≤ .03) and cognitive flexibility (19% [95% CI, 5%-33%] better, P = .02). Brief hypoglycemia evoked by TGC was not associated with worse neurocognitive outcome. CONCLUSION: At follow-up, children who had been treated with TGC during an ICU admission did not have a worse measure of intelligence than those who had received UC. TRIAL REGISTRATION: clinicaltrials.gov Identifier NCT00214916.

15-Year follow-up of regional right and left ventricular function after the Senning operation: a Colour-Doppler myocardial imaging study.

INTRODUCTION: Despite right ventricular (RV) dysfunction being a major concern in Senning patients, long-term follow-up data is lacking. This study aimed (1) at evaluating regional (base-mid-apex) RV and left ventricular (LV) function using Colour-Doppler myocardial imaging over a 15-year follow-up period and (2) at comparing results with matched controls. METHODS: For the longitudinal analysis (2004-2019), we compared systolic and diastolic function in 10 Senning patients. For the cross-sectional analysis, we compared the subaortic RV (sRV) of Senning patients with the RV and LV of matched controls and the subpulmonary LV (spLV) of Senning patients with the LV of matched controls. RESULTS: The longitudinal analysis of sRV function showed a significant decrease in apical peak systolic strain (-17 ± 7% vs -12 ± 4%; p = 0.025) and apical peak systolic strain rate (-1.1 ± 0.3s-1 vs -0.8 ± 0.4s-1; p = 0.012). spLV function showed a significant decrease in peak systolic velocity (mid; p = 0.013 and apex; p = 0.011) and peak systolic strain rate (mid; p = 0.048). The cross-sectional analysis revealed significant lower values for basal, mid and apical peak systolic velocity, peak systolic strain rate, peak systolic strain of the sRV of Senning patients when compared to both LV and RV of matched controls (all p < 0.05). CONCLUSION: Our study showed that systolic and diastolic sRV function did not change over a 15-year follow-up period, except in the apical region. There was a decline in spLV systolic function, which may be of clinical value. On the other hand, when compared to age- and gender-matched controls, the sRV of Senning patients exhibits significantly decreased measurements of longitudinal systolic function.

Array comparative genomic hybridization as a diagnostic tool for syndromic heart defects.

OBJECTIVES: To investigate different aspects of the introduction of array comparative genomic hybridization (aCGH) in clinical practice. STUDY DESIGN: A total 150 patients with a syndromic congenital heart defect (CHD) of unknown cause were analyzed with aCGH at 1-Mb resolution. Twenty-nine of these patients, with normal results on 1Mb aCGH, underwent re-analysis with 244-K oligo-microarray. With a logistic regression model, we assessed the predictive value of patient characteristics for causal imbalance detection. On the basis of our earlier experience and the literature, we constructed an algorithm to evaluate the causality of copy number variants. RESULTS: With 1-Mb aCGH, we detected 43 structural variants not listed as clinically neutral polymorphisms, 26 of which were considered to be causal. A systematic comparison of the clinical features of these 26 patients to the remaining 124 patients revealed dysmorphism as the only feature with a significant predictive value for reaching a diagnosis with 1-Mb aCGH. With higher resolution analysis in 29 patients, 75 variants not listed as clinically neutral polymorphisms were detected, 2 of which were considered to be causal. CONCLUSIONS: Molecular karyotyping yields an etiological diagnosis in at least 18% of patients with a syndromic CHD. Higher resolution evaluation results in an increasing number of variants of unknown significance.

Bailout stenting for critical coarctation in premature/critical/complex/early recoarcted neonates.

BACKGROUND: Surgical repair of critical coarctation can be problematic in premature, critical, complex, or early postoperative neonates. OBJECTIVES: We aimed to review our experience with stent implantation to defer urgent surgery to an elective time. METHODS: Fifteen neonates with severe aortic coarctation: five premature-hypotrophic (1,400-2,000 g), six critical and complex cardiac malformation, four early (1 day [0-2 days]; median [range]) after surgical coarctectomy or complex arch reconstruction. Bare coronary stents (diameter 4.0 [3.5-5.0] mm; length 10 [8-16] mm) were used. Stents were removed surgically depending on clinical needs. RESULTS: Adequate aortic flow was obtained in 15 patients. The femoral artery was preserved in 13/15 patients. Two deaths occurred before stent removal and were nonprocedure related. In patients with simple stented coarctation, the stent was removed after 2.8 [0.2-5.0] months. In complex cardiac malformation, stents were finally removed 3.0 [0.2-78] months after implantation. SURGICAL TECHNIQUE: simple coarctectomy end-to-end in eight, extensive arch patch reconstruction in four. One patient is awaiting stent removal. The final maximum systolic velocity (cw-Doppler) across the aortic arch was 1.7 [1.2-2.5] m/sec. CONCLUSIONS: In premature/critical/complex neonates with severe coarctation, bailout stenting followed by early or late surgical coarctectomy appears a promising concept.

Stent expansion of stretch Gore-Tex grafts in children with congenital heart lesions.

OBJECTIVE: To evaluate the efficacy and safety of expanding vascular shunt grafts beyond original nominal diameter using stents. METHODS: Bench testing confirmed the expandability of 3.5 mm and 4.0 mm vascular Gore-Tex stretch grafts. A retrospective analysis included eleven systemic to pulmonary artery shunts with diminished flow which were stented with the aim of increasing the original nominal diameter of the shunts. RESULTS: During bench testing, the grafts could be expanded to 4.5 mm and 5.8 mm, respectively. Fourteen stents were implanted in 11 stretch grafts a median of 18.9 months (3.2; 21.6 months) after shunt surgery. There was a median increase in diameter of 1.4 mm (0.9; 1.7 mm) [P = 0.001, 95% CI: 0.47; 1.7) from original nominal to final stented diameter of the shunts with a median gain of 28%. A simultaneous improvement in saturations from a median of 73% (66; 77%) to 87% (84; 89%) [P = 0.015; 95% CI: 3; 22] was observed. No complications were experienced during the procedures. CONCLUSION: In our limited experience, stretch Gore-Tex vascular grafts can be safely expanded beyond nominal diameters using high pressure vascular stents. This leads to improvement in saturation and pulmonary blood flow. It allows the clinician to tailor pulmonary flow in relation to pulmonary artery size and growth, ensuring best possible timing for the next surgical procedure.

The influence of pulmonary regurgitation on regional right ventricular function in children after surgical repair of tetralogy of Fallot.

AIMS: Pulmonary regurgitation after repair of tetralogy of Fallot (TOF) results in right ventricular (RV) dysfunction with significant late morbidity and mortality. The aim was to assess the influence of pulmonary regurgitation on regional RV function. METHODS AND RESULTS: In 48 asymptomatic children (age 11.1 +/- 3.3 years) with repair of TOF, peak systolic strain rate (SR) and end-systolic strain (epsilon) were acquired using colour Doppler myocardial imaging. RV indices were quantified by magnetic resonance imaging. Echocardiography and exercise capacity was also performed. Forty complete data sets were analysed. An inverse linear relationship was demonstrated between the degree of pulmonary regurgitation and right ventricle end-systolic epsilon (r = -0.53, P < 0.01) as well as a correlation with peak systolic SR (r = -0.35, P < 0.01). A correlation existed between peak VO(2) and peak systolic SR (r = 0.51, P = 0.001) and end-systolic epsilon (r = 0.33, P < 0.05). CONCLUSION: In asymptomatic children after repair of TOF, pulmonary regurgitation is associated with impaired regional systolic RV deformation indices. Regional strain and SR may be an early indicator of RV dysfunction in patients with post-TOF and pulmonary regurgitation.

Premature foetal closure of the arterial duct: clinical presentations and outcome.

AIMS: The prevalence of intra-uterine ductal dysfunction is unknown and the clinical consequences are poorly understood. The aim of this study was to investigate the echocardiographic (ECHO) abnormalities and outcomes of this rare phenomenon. METHODS AND RESULTS: Retrospective analysis of foetal (n = 602) and neonatal ECHO databases (n = 1477) between 1998 and 2007. Clinical and imaging studies were reviewed for pathology due to or associated with premature closure of the duct. Twelve cases were identified. Eight (1.3%) were diagnosed pre-natally at a median gestational age of 29.0 weeks (range: 20.0-37.5 weeks). Four neonates (0.3%) with significant cyanosis and absence of the arterial duct were also included. The most common ECHO features were: excessive right ventricular (RV) hypertrophy (100%), more than expected tricuspid and pulmonary regurgitation (100% and 92%, respectively), and right atrial dilation (75%). Premature induction of delivery was advised for five patients. Neonatal therapy consisted of observation and oxygen administration (n = 7), ventilation with pulmonary vasodilators (n = 5), and one required extracorporeal membrane oxygenation. There were three deaths due to respiratory failure with severe pulmonary hypertension. During follow-up, two children required additional right heart procedures and one developed a non-compaction cardiomyopathy. CONCLUSION: Foetal premature closure of the arterial duct causes stress at different foetal ages and many different levels of the right heart and pulmonary circulation, resulting in a wide range of secondary pathology. Disproportionate RV hypertrophy is the most common finding. Clinical outcomes range from mild symptomatology to lethal respiratory insufficiency.