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.

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.

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.

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.

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.

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.

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.

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.

Clinical Characteristics of Infective Endocarditis in Children.

BACKGROUND: Infective endocarditis (IE) remains a diagnostic and therapeutic challenge associated with high morbidity and mortality. We evaluated the microbial profile and clinical manifestation of IE in children. METHODS: A retrospective study examining pediatric IE cases treated between 2000 and 2017 at the Department of Pediatric Cardiology, KU Leuven, was conducted. Clinical presentation, treatment, complications, outcome of IE, underlying microorganisms and congenital heart defects were reviewed. RESULTS: Fifty-three patients were diagnosed with IE. Overall, 19 patients (36%) required cardiac surgery. Seven patients (13%) died. Eighty-seven percent of patients had an underlying congenital cardiac defect. Eighteen (34%) children presented with prosthetic graft IE. A causative organism was found in 49 (92%) cases: viridans group streptococci were identified in 17 (32%), Staphylococcus aureus in 13 (25%) and coagulase-negative staphylococci in 11 (20%) children. Community-acquired (CA) IE increased significantly from 8 (33%) cases in 2000-2007 to 20 (74%) cases in 2008-2017 (P < 0.01). Even with viridans streptococci being significantly more prevalent in the CA group (P < 0.01), we did not observe an increase of streptococcal IE from 2008 to 2017. Seventeen (32%) patients presented with hospital-acquired IE during the first year of life with 14 (82%) children after surgery and a prevalence of coagulase-negative staphylococci (53%). CONCLUSIONS: The incidence of pediatric IE was similar over the investigated time period with a shift toward CA IE. Streptococci and staphylococci accounted for the majority of cases in both periods. Awareness of IE and its prevention is crucial in patients after implantation of prosthetic grafts.

Up to 11 years of experience with the Melody valved stent in the right ventricular outflow tract.

AIMS: The aim of the study was to report up to 11 years of follow-up after Melody valve implantation in the pulmonary position. METHODS AND RESULTS: This was a single-institution non-randomised prospective observational study of all Melody valves in the pulmonary position after discharge between 2006 and 2017 (n=188). Mean age was 19.4 years (SD 13.2). The indication was stenosis (45%), regurgitation (33%) and mixed (22%). Pre-stenting was performed in all except the initial four patients. In stenotic lesions the peak gradient was 36 mmHg PIG (SD 12.0) after 11 years and in regurgitant lesions the maximal regurgitation was 2/4. Stent fractures were observed in 8.6%; only one grade III fracture required redo PPVI. Surgical removal was carried out in seven (3.7%), redo PPVI in five (2.7%). Endocarditis was diagnosed in 19 (10.2%) patients at a median of 2.3 years (0.7-8.8) after Melody implantation. Three were surgically removed early because of persistent infection, 16 were sterilised; six required replacement (three surgical, three redo PPVI). There were no valve- or procedure-related deaths. CONCLUSIONS: The Melody valve shows a good preserved leaflet function up to 11 years after implantation. The main reason for graft failure was endocarditis, although in half of those patients no reintervention was needed. After pre-stenting, stent fractures led very exceptionally to reintervention.

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.

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.

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.

Bailout shunt/banding for backward left heart failure after adequate neonatal coarctectomy in borderline left hearts.

OBJECTIVES: To determine the outcome of a bailout procedure using the right ventricle to re-assist the left ventricle in neonates after technically adequate coarctectomy but a failing borderline left heart. METHODS: The surgical procedure was performed on bypass. A 'reversed' 6-mm surgical shunt was inserted between the pulmonary trunk and the descending aorta together with bilateral branch pulmonary artery banding. RESULTS: Over a 10-year period, 89 neonates presented with coarctation and small left hearts. In 9 neonates, a hybrid procedure was performed at the outset. The remaining 80 underwent extended end-to-end coarctectomy. Two of these, despite adequate coarctectomy, developed retrograde cardiac failure with supra-systemic pulmonary hypertension, dilating right ventricles and progressive cardiogenic shock. The progressively dilating right ventricles inhibited left ventricular filling. Reversed surgical shunts were performed at 9 and 7 days post-coarctectomy. Both infants recovered rapidly and could be extubated after 4 and 7 days, respectively. Patient 1 proceeded to a univentricular repair and Patient 2 to a biventricular repair. CONCLUSIONS: Reversed surgical shunt with bilateral banding of the branch pulmonary arteries after neonatal coarctectomy can be successfully employed as a bailout procedure in cases where a borderline left heart with growth potential cannot tolerate a biventricular circulation. It may act as an acute life-saving measure as well as a bridge to later repair. If high risk for backward failure exists in a borderline left heart with catch-up growth potential, a primary hybrid procedure is probably a more elegant and predictable strategy.

Infective endocarditis of a transcatheter pulmonary valve in comparison with surgical implants.

BACKGROUND: Melody valved stents (Medtronic Inc, Minneapolis, Minnesota, USA) have become a very competitive therapeutic option for pulmonary valve replacement in patients with congenital heart disease. After adequate prestenting of the right ventricular outflow tract (RVOT) Melody valved stents have a good medium term functional result but are exposed to infective endocarditis (IE). PATIENTS AND METHODS: Retrospective study of tertiary centre Congenital Heart Disease database; to compare incidence of IE in three different types of valved conduits in RVOT: Melody valved stent, cryopreserved homograft (European Homograft Bank) and Contegra graft (Medtronic Inc). RESULTS: Between 1989 and 2013, 738 conduits were implanted in 677 patients. 107 Melody valved stents were implanted in 107 patients; IE occurred in 8 (7.5%) patients during a follow-up of 2.0 years (IQR 2.4 years, range 0.3-7.8 years). 577 Homografts were implanted in 517 patients; IE occurred in 14 patients (2.4%) during a median follow-up of 6.5 years (IQR 9.2 years; range 0.1-23.7 years). Finally, 54 Contegra grafts were implanted in 53 patients; 11 patients (20.4%) had IE during a follow-up of 8.8 years (IQR 7.7 years; range 0.2-3.5 years). Survival free of IE by Kaplan-Meier for homografts was 98.7% at 5 years and 97.3% at 10 years; for Contegra 87.8% at 5 years and 77.3% at 10 years and for Melody 84.9% at 5 years (log-rank test; p<0.001). CONCLUSIONS: The Contegra conduit and Melody valved stents have a significantly higher incidence of IE than homografts. IE is a significant threat for long-term conduit function.

Medium term follow-up after percutaneous pulmonary valve replacement with the Melody® valve.

INTRODUCTION: Data on long term function of the Melody valve are scarce. Patients and methods: single institution; results of percutaneous pulmonary valve implantation (PPVI) from 2006 to 2014. The function of the valved conduit was analyzed by Doppler echocardiography. Annual Chest X-ray after implant and permanent screening for events (e.g. Endocarditis). RESULTS: 112 Melody valves were implanted in 111 patients; mean age 19.3 years (4.5-81.6). No pre-stenting of the RVOT was performed (n = 4) at first. In the next 107 patients pre-stenting was always performed. In 82 patients 1 pre-stent, 18 patients 2, in 6 patients 3 stents and 1 patient 4 stents were used. The Melody stent was dilated up to 24 mm (n = 4), 22 mm (n = 72), 20 mm (n = 28) and 18 mm (n = 6). When stenotic, the Doppler gradient reduced from 67.0 mm Hg (SD 13.9) to 18.9 mm Hg (SD 10.4) (p < 0.001); pulmonary regurgitation (PR) was reduced from median 3.5/4 (range 0-4/4) to none or trivial (p < 0.001). There was no significant change in RVOT peak velocity at 5 years (p = 0.122) nor PR (p = 0.835). Type 1 stent fractures were observed in 1/4 non-pre-stented patients and in 5/107 pre-stented (p < 0.05). Endocarditis occurred in 8/112 valves; freedom of endocarditis was 85% at 5 years. In 2 patients early surgical replacement was necessary. Six were sterilized with antibiotic treatment; 2 patients required re-stenting and re-PPVI due to residual gradient. CONCLUSION: Adequate pre-stenting of the RVOT before PPVI nearly abolishes or delays stent fracture. Cusp function is well preserved in mid-term follow-up; endocarditis is a threat.

Use of covered Cheatham-Platinum stents in congenital heart disease.

BACKGROUND: Controversy remains regarding the use of covered stents in congenital heart disease (CHD). We evaluate the possibilities and safety of covered Cheatham-Platinum (CCP) stents in CHD. METHODS: Single-center retrospective CHD-database study of all CCP stents, 2003-2012. Three study groups: aortic coarctation (CoA), right ventricular outflow tract pre-stenting for percutaneous revalvulation (RVOT), and miscellaneous. Continuous data expressed as median (range). RESULTS: 114 CCP stents in 105 patients, age 16.8 years (4.2-71.2). CoA group: 54 CCP stents in 51 patients: 3/54 for aneurysm exclusion, in 51/54 covering used "prophylactically" because of increased risk for vessel tear. Overall, CCP stenting increased the coarctation diameter from 6mm (0-15) to 15 mm (10-20) (p<0.001). RVOT group: 39 CCP stents in 37 patients (34 with RVOT graft, 3 with transannular patch): the graft lumen had shrunken from nominal 21 mm (10-26) to 13 mm (5-22); with the CCP stent the RVOT was redilated to 22 mm (16-26, p<0.001 vs stenosis). Miscellaneous group: 21 CCP stents in 17 patients: closure of Fontan-circuit fenestration (n=5), restoration of superior caval vein (n=2) or pulmonary artery (n=3) patency, relief of supra-pulmonary stenosis (n=2), exclusion of aberrant pulmonary arteries (n=1), cavopulmonary conduit expansion (n=2), Blalock-Taussig shunt flow reduction (n=1), and defibrillator lead protection from sharp stents (n=1). Hybrid procedures performed in 3/17 patients. CCP stent was used as rescue treatment in 2/patients to seal iatrogenic bleeding. CONCLUSION: CCP stents can safely be applied in CHD patients. The covering allows adequate sealing of existing or expected tears, thereby increasing the safety margin with more complete dilation.

Neonatal circulatory failure due to acute hypertensive crisis: clinical and echocardiographic clues.

OBJECTIVE: Circulatory failure due to acute arterial hypertension in the neonatal period is rare. This study was undertaken to assess the clinical and echocardiographic manifestations of circulatory failure resulting from acute neonatal hypertensive crisis. METHODS: Neonatal and cardiology databases from 2007 to 2010 were reviewed. An established diagnosis of circulatory failure due to neonatal hypertension before the age of 14 days was required for inclusion. Six patients were identified. RESULTS: Five patients presented with circulatory failure due to an acute hypertensive crisis. The median age at presentation was 8.5 days (range: 6.0-11.0) with a median body weight of 3.58 kg (range: 0.86-4.70). Echocardiography demonstrated mild left ventricular dysfunction [median shortening fraction (SF) 25%, range 10-30] and mild aortic regurgitation in 83% (5/6) of patients. One patient with left ventricular dysfunction (SF = 17%) had a large apical thrombus. Two patients were hypotensive, and hypertension only became evident after restoration of cardiac output. Administration of intravenous milrinone was successful, with rapid improvement of the clinical condition. Left ventricular function normalised in all survivors. CONCLUSION: Early neonatal circulatory collapse due to arterial hypertension is a rare but potentially life-threatening condition. At presentation, hypotension, especially in the presence of a dysfunctional left ventricle, does not exclude a hypertensive crisis being the cause of circulatory failure. The echocardiographic presence of mild aortic regurgitation combined with left ventricular hypocontractility in a structurally normal heart should alert the physician to the presence of underlying hypertension.

Cardiovascular pathology in males and females with 45,X/46,XY mosaicism.

CONTEXT: The phenotype of 45,X/46,XY mosaicism is heterogeneous ranging from females with Turner syndrome (TS) to apparently normal males. Males with 45,X/46,XY frequently show stigmata typically associated with TS. We hypothesised that males with 45,X/46,XY have similar cardiovascular pathology as females with 45,X/46,XY. OBJECTIVE: To investigate cardiovascular abnormalities in 45,X/46,XY males and to compare them with 45,X/46,XY females. DESIGN: Patients with 45,X/46,XY mosaicism were selected from the Belgian Registry for Growth and Puberty problems and via the multidisciplinary clinic for disorders of sexual development. PATIENTS: EIGHTEEN PATIENTS WERE INCLUDED: 8 raised as females (F) and 10 as males (M). INTERVENTION: Complete cardiac examination with blood pressure measurement, ECG, echocardiography and MRI. MAIN OUTCOME MEASUREMENT: Cardiac parameters were registered for both groups. In a second phase, clinical features and external masculinisation score (EMS) were retrospectively collected from the medical files. RESULTS: A structural heart defect was diagnosed before inclusion in 1 F with coarctation and 1 M with spontaneously closed VSD. A bicuspid aortic valve was found in 8 (3 F, 5 M). Dilation of the ascending aorta was present in 4 M and was severe in 2 young boys. QTc was prolonged in 3 F and 2 M. CONCLUSION: Males with 45,X/46,XY mosaicism have similar cardiovascular pathology as 45,X/46,XY females. Dilation of the ascending aorta can be important, also in males. We advise cardiac screening and life-long monitoring in all males with 45,X/46,XY mosaicism according to the existing guidelines for Turner syndrome.

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.