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Background Patients with pulmonary vein stenosis (PVS) often require frequent transcatheter pulmonary vein (PV) interventions for management of restenosis. Predictors of serious adverse events (AEs) and need for high-level cardiorespiratory support (mechanical ventilation, vasoactive support, and/or extracorporeal membrane oxygenation) 48 hours after transcatheter PV interventions have not been reported. Methods Single-center retrospective cohort analysis of patients with PVS who underwent transcatheter PV interventions from 3/1/2014 to 12/31/2021. Univariate and multivariable analyses were performed using generalized estimating equations to account for within-patient correlation. Results 240 patients underwent 841 catheterizations involving PV interventions (median 2 catheterizations per patient [1, 3]). At least one serious AE was reported in 100 (12%) cases, the most common of which were pulmonary hemorrhage (n = 20) and arrhythmia (n = 17). There were 14 severe/catastrophic AEs (1.7% of cases) including 3 strokes and 1 patient death. On multivariable analysis, age less than 6 months, low systemic arterial saturation (

Evaluate the efficacy of systemic sirolimus (rapamycin) in preventing in-stent stenosis (ISS) in pediatric intraluminal pulmonary vein stenosis (PVS). Report the adverse events related to sirolimus therapy. There is a high incidence of ISS following stent implantation in PVS. The use of sirolimus in preventing ISS has not been reported. Retrospective review of all patients who received sirolimus (8 week course) for treatment of ISS for PVS between January 2013 and June 2018. Forty stents (37 bare metal, 3 drug-eluting) in 20 patients were treated with sirolimus; 20 at the time of implantation (primary prevention [1P]) and 20 following documented ISS requiring transcatheter reintervention (secondary prevention [2P]). Treated patients were young (median 2 y/o [0.7–5.7]) and most had PVS associated with congenital heart disease (75%, 15/20; 4/15 with TAPVC). In the 1P group, 85% (17/20) of stents were without significant (< 50%) ISS at median of 102 days (range 56–527); the growth rate of ISS in this group was 7.5 ± 7.1%/month. In the 2P group, most stents had a slower growth rate of ISS after sirolimus therapy compared to pre-treatment (median 3.7 [− 0.2 to 13.1] vs. 10.4 [1.3 to 19.5] %/month; p

The AngioVac System (AVS) extracts venous and pulmonary artery (PA) thrombi. We report modified use of the second-generation AVS with concurrent venoarterial extracorporeal membrane oxygenation (VA-ECMO) in a 10-year-old, 23 kg patient with failing Fontan circulation due to acute-on-chronic Fontan and PA thrombosis. Emergent femoral VA-ECMO was initiated for profound hypoxemia during cardiac catheterization. Fluoroscopy-guided thrombo-embolectomy was performed with AVS components. A two-venous limb inflow cannulation strategy was used; the AngioVac cannula (AVC) was positioned in the central PA and joined to the existing ECMO venous-limb. Thrombus extraction proceeded by clamping the ECMO venous-limb with the existing VA-ECMO centrifugal pump generating negative pressure to the AVC. Extracorporeal membrane oxygenation arterial-limb access was used for blood return. Settings to avoid cavitation were a maximal negative pressure of 100 mmHg using

Background Troponin levels are frequently obtained in pediatric patients, but the benefit remains unclear. Methods and Results This retrospective study included 1993 patients aged 0 to 21 years without history of cardiac disease in whom troponin levels were obtained during clinical evaluation of cardiac and noncardiac presentations. Troponin was elevated (≥0.1 ng/mL) in 182 patients (9%). A cardiac diagnosis was made in 109 (60%) of those with elevated troponin and in 208 (12%) of those without ( P Conclusions Troponin can be a useful adjunctive test in the evaluation of children when the differential diagnosis includes cardiac etiologies. Serial measurement was not helpful when troponin was elevated at presentation but may merit consideration when the initial level is not elevated and there is ongoing concern about cardiac involvement. Lower reference values may be appropriate when evaluating children in contrast to adults.

IntroductionThe optimal approach to unifocalisation in pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (pulmonary artery/ventricular septal defect/major aortopulmonary collaterals) remains controversial. Moreover, the impact of collateral vessel disease burden on surgical decision-making and late outcomes remains poorly defined. We investigated our centre’s experience in the surgical management of pulmonary artery/ventricular septal defect/major aortopulmonary collaterals.Materials and methodsBetween 1996 and 2015, 84 consecutive patients with pulmonary artery/ventricular septal defect/major aortopulmonary collaterals underwent unifocalisation. In all, 41 patients received single-stage unifocalisation (Group 1) and 43 patients underwent multi-stage repair (Group 2). Preoperative collateral vessel anatomy, branch pulmonary artery reinterventions, ventricular septal defect status, and late right ventricle/left ventricle pressure ratio were evaluated.ResultsMedian follow-up was 4.8 compared with 5.7 years for Groups 1 and 2, respectively, p = 0.65. Median number of major aortopulmonary collaterals/patient was 3, ranging from 1 to 8, in Group 1 compared with 4, ranging from 1 to 8, in Group 2, p = 0.09. Group 2 had a higher number of lobar/segmental stenoses within collateral vessels (p = 0.02). Group 1 had fewer catheter-based branch pulmonary artery reinterventions, with 5 (inter-quartile range from 1 to 7) per patient, compared with 9 (inter-quartile range from 4 to 14) in Group 2, p = 0.009. Among patients who achieved ventricular septal defect closure, median right ventricle/left ventricle pressure was 0.48 in Group 1 compared with 0.78 in Group 2, p = 0.03. Overall mortality was 6 (17%) in Group 1 compared with 9 (21%) in Group 2.DiscussionSingle-stage unifocalisation is a promising repair strategy in select patients, achieving low rates of reintervention for branch pulmonary artery restenosis and excellent mid-term haemodynamic outcomes. However, specific anatomic substrates of pulmonary artery/ventricular septal defect/major aortopulmonary collaterals may be better suited to multi-stage repair. Preoperative evaluation of collateral vessel calibre and function may help inform more patient-specific surgical management.

Apixaban is well studied in adults; paediatric data are extremely limited. We describe 3 children (age 2–6 years, weight 13–17 kg) with congenital heart disease who developed intracardiac thrombosis, and in whom typical treatments had failed (in 1) or were considered impractical (in 2). All were treated with apixaban 2.5 mg orally twice daily with complete (in 2) or partial (in 1) thrombus resolution and no clinical bleeding events.

Congenital heart valve disease has life-threatening consequences that warrant early valve replacement; however, the development of a growth-accommodating prosthetic valve has remained elusive. Thousands of children continue to face multiple high-risk open-heart operations to replace valves that they have outgrown. Here, we demonstrate a biomimetic prosthetic valve that is geometrically adaptable to accommodate somatic growth and structural asymmetries within the heart. Inspired by the human venous valve, whose geometry is optimized to preserve functionality across a wide range of constantly varying volume loads and diameters, our balloon-expandable synthetic bileaflet valve analog exhibits similar adaptability to dimensional and shape changes. Benchtop and acute in vivo experiments validated design functionality, and in vivo survival studies in growing sheep demonstrated that mechanical valve expansion accommodated growth. As illustrated in this work, dynamic size adaptability with preservation of unidirectional flow in prosthetic valves thus offers a paradigm shift in the treatment of heart valve disease.

Background: Surgical and transcatheter bioprosthetic valves (BPVs) in the pulmonary position in patients with congenital heart disease may ultimately fail and undergo transcatheter reintervention. Angiographic assessment of the mechanism of BPV failure has not been previously described. Aims: The aim of this study was to determine the mode of BPV failure (stenosis/regurgitation) requiring transcatheter reintervention and to describe the angiographic characteristics of the failed BPVs and report the types and efficacy of reinterventions. Materials and Methods: This is a retrospective single-center review of consecutive patients who previously underwent pulmonary BPV placement. (surgical or transcatheter) and subsequently underwent percutaneous reintervention from 2005 to 2014. Results: Fifty-five patients with surgical. (41) and transcutaneous pulmonary valve. (TPV) (14) implantation of BPVs underwent 66 catheter reinterventions. The surgically implanted valves underwent fifty reinterventions for indications including 16 for stenosis, seven for regurgitation, and 27 for both, predominantly associated with leaflet immobility, calcification, and thickening. Among TPVs, pulmonary stenosis. (PS) was the exclusive failure mode, mainly due to loss of stent integrity. (10) and endocarditis. (4). Following reintervention, there was a reduction of right ventricular outflow tract gradient from 43 ± 16 mmHg to 16 ± 10. mmHg (P < 0.001) and RVp/AO ratio from 0.8 ± 0.2 to 0.5 ± 0.2 (P < 0.001). Reintervention with TPV placement was performed in 45. (82%) patients. (34 surgical, 11 transcatheter) with no significant postintervention regurgitation or paravalvular leak. Conclusion: Failing surgically implanted BPVs demonstrate leaflet calcification, thickness, and immobility leading to PS and/or regurgitation while the mechanism of TPV failure in the short- to mid-term is stenosis, mainly from loss of stent integrity. This can be effectively treated with a catheter.based approach, predominantly with the valve-in-valve technique.

Visual Abstract, Highlights • Mitochondrial transplantation uses mitochondria isolated from the patient’s own body to replace or augment native mitochondria damaged by ischemia reperfusion injury. • The transplanted mitochondria can be delivered to the myocardium by intra-coronary injection. • Intracoronary injection of mitochondria is safe and has no effect on coronary patency. • Intracoronary injection of mitochondria provides for the rapid uptake and specific biodistribution of mitochondria throughout the heart. • Intracoronary mitochondrial transplantation is efficacious and provides for enhanced post-ischemic myocardial function, improved coronary blood flow and reduction of infarct size., Summary Mitochondrial dysfunction is the determinant insult of ischemia-reperfusion injury. Autologous mitochondrial transplantation involves supplying one’s healthy mitochondria to the ischemic region harboring damaged mitochondria. The authors used in vivo swine to show that mitochondrial transplantation in the heart by intracoronary delivery is safe, with specific distribution to the heart, and results in significant increase in coronary blood flow, which requires intact mitochondrial viability, adenosine triphosphate production, and, in part, the activation of vascular KIR channels. Intracoronary mitochondrial delivery after temporary regional ischemia significantly improved myocardial function, perfusion, and infarct size. The authors concluded that intracoronary delivery of mitochondria is safe and efficacious therapy for myocardial ischemia-reperfusion injury.

Pulmonary arteriovenous malformations (PAVMs) are thought to form as a result of exclusion of hepatic venous blood from part of the pulmonary circulation. Surgical arteriovenous (AV) fistula creation has demonstrated therapeutic potential to reverse PAVM formation. We sought to demonstrate the feasibility and safety of transcatheter AV fistula creation for this indication. Fluoroscopically guided puncture from the basilic vein into the brachial artery using a Brockenbrough needle and sharpened 0.014" wire created a tract between these vessels. After balloon dilation of the tract, a covered stent was deployed, resulting in a functioning brachial AV fistula. The procedure was technically successful, with no clinical complications at 4 months follow-up. Repeat diagnostic catheterization revealed marked improvement in systemic saturation and near-resolution of PAVMs in the pilot patient. This report suggests that transcatheter brachial arteriovenous fistula formation is technically feasible, and may be effective in managing PAVMs in select single-ventricle patients.

Introduction. Standardization of care can reduce practice variation, optimize resource utilization, and improve clinical outcomes. We have created a standardized clinical assessment and management plan (SCAMP) for patients having balloon aortic valvuloplasty (BAV) for congenital aortic stenosis (AS). This study compares acute outcomes of BAV at our institution before and after introduction of this SCAMP. Methods. In this retrospective matched cohort study, each SCAMP patient was matched to four historical controls. Outcomes were categorized based on the combination of residual AS and aortic regurgitation (AR) as: (1) Optimal: gradient ≤35 mm Hg and trivial or no AR; (2) Adequate: gradient ≤35 mm Hg and mild AR; (3) Inadequate: gradient >35 mm Hg and/or moderate or severe AR. Results. All 23 SCAMP patients achieved a residual AS gradient ≤35 mm Hg; the median residual AS gradient for the SCAMP group was lower (25 (10-35) mm Hg) than in matched controls (30 (0-65) mm Hg; P = 0.005). The two groups did not differ with regard to degree of AR grade after BAV. Compared with controls, SCAMP patients were more likely to have an optimal result and less likely to have an inadequate result (52% vs. 34% and 17% vs. 45%, respectively; P = 0.02) Conclusions. A SCAMP for BAV resulted in optimal acute results in half of the initial 23 patients enrolled, and outcomes in this group were better than those of matched historical controls. Whether these improved acute outcomes translate into better long-term outcomes for this patient population remains to be seen.

Background— Percutaneous pulmonary valve implantation using a stent-based bioprosthetic valve provides an alternative to surgery in select patients. Systemic infections in Melody valve–implanted patients with and without identified valve involvement have been reported, yet the incidence is unknown, and risk factors remain unidentified. Methods and Results— Between 2007 and 2012, a total of 147 consecutive patients with congenital heart disease underwent Melody percutaneous pulmonary valve implantation at our institution. Demographic and clinical variables were collected at baseline and at follow-up and analyzed as predictors. The occurrence of bloodstream infection (BSI), defined as a bacterial infection treated with ≥4 weeks of antibiotics, served as our primary outcome. The mean age at implantation for the study population was 21.5±11 years, and tetralogy of Fallot was the cardiac condition in 59%. During a median follow-up of 19 months, 14 patients experienced BSI (9.5%; 95% confidence interval, 5.3%–15%). Of these, 4 (2.7%) patients had Melody valve endocarditis. Two patients died during the event, neither of whom had known valve involvement. The median procedure to infection time was 15 months (range, 1–56). In univariate analysis, male sex, previous endocarditis, in situ stents in the right ventricular outflow tract, and presence of outflow tract irregularities at the implant site were associated with BSI occurrence. Conclusions— In this cohort, 9.5% of patients who underwent Melody percutaneous pulmonary valve implantation experienced subsequent BSI, occurring 1 to 56 months after implant, and 2.7% of patients had prosthetic endocarditis. Our findings suggest that patient and nonvalve anatomic factors may be associated with BSI after percutaneous pulmonary valve implantation.

Background Patients with severe pulmonary arterial hypertension (PAH) face significant morbidity and death as a consequence of progressive right heart failure. Surgical shunt placement between the left PA and descending aorta (Potts shunt) appears promising for PAH palliation in children; however, surgical mortality is likely to be unacceptably high in adults with PAH. Methods We describe a technique for transcatheter Potts shunt (TPS) creation by fluoroscopically guided retrograde needle perforation of the descending aorta at the site of apposition to the left PA to create a tract for deployment of a covered stent between these vessels. This covered stent—anchored by the vessel walls and surrounding tissue—serves as the shunt. Results TPS creation was considered in 7 patients and performed in 4. The procedure was technically successful in 3 patients; 1 patient died during the procedure as a result of uncontrolled hemothorax. One acute survivor, critically ill at the time of TPS creation, later died of comorbidities. The 2 mid-term survivors (follow-up of 10 and 4 months) are well at home, with symptomatic improvement and no late complications. The 3 candidate patients in whom the procedure was not performed died within 1 month of consideration, underscoring the tenuous nature of this population. Conclusions TPS creation is feasible and may offer symptomatic relief to select patients with refractory PAH. Further study of this innovative approach is warranted.

Background Patients with congenital heart disease carry a high burden of arrhythmias and may pose special challenges when these arrhythmias are addressed invasively. We sought to describe our early experience with radiofrequency (RF) needle transseptal perforation to facilitate ablation procedures in this population. Methods Retrospective chart review to identify all cases of attempted transseptal access with a commercial RF needle at Children's Hospital Boston between February 2007 and January 2010. Results A total of 10 patients had attempted RF transseptal perforation. Median age was 27 years. Five patients had undergone atrial switch procedures (Mustard/Senning), four had undergone Fontan operations, and one had atrial septal defect repair. The indication for left atrial access was mapping/ablation of atrial flutter in nine cases, and left-sided accessory pathway in one case. The RF needle was chosen primarily in eight of 10 cases, whereas in the remaining two cases RF was used only after failed attempts with a conventional Brockenbrough needle. Septal material was atrial muscle in five cases, pericardium in three, and synthetic fabric in two. In nine of 10 patients, RF transseptal perforation was successful, including both patients in whom a conventional needle had failed. There were no clinically significant complications. Conclusions RF transseptal perforation can be an effective method of obtaining left atrial access for electrophysiologic procedures in patients with complex congenital heart disease, including cases where a conventional Brockenbrough needle has failed.

Patients with a borderline left ventricular hypoplasia in the hypoplastic left heart syndrome variant or an unbalanced atrioventricular canal who undergo initial single-ventricle palliation may be candidates for biventricular (BiV) conversion following left ventricle (LV) recruitment procedures. We investigated associations among preoperative parameters and postoperative outcomes in patients undergoing BiV conversion.We performed a retrospective review of patients who underwent BiV conversion to determine variables associated with clinical outcomes. Predictor variables included cardiac diagnosis, age and weight, LV dimension, LV end diastolic volume, LV mass, preoperative LV end diastolic pressure (LVEDP), and preoperative left atrial pressure. Primary outcome was a composite of death, heart transplant, or BiV takedown.Of 51 patients, 11 experienced primary outcome (22%). Patients with hypoplastic left heart syndrome variant were more likely to experience primary outcome than those with an unbalanced atrioventricular canal (30% vs 6%; P = .03). Receiver operating characteristic analysis demonstrated that preoperative LVEDP had good predictive accuracy in classifying patients with and without the primary outcome (area under the curve, 0.757; 95% confidence interval, 0.594-0.919; P = .012). The Youden J-index indicated a cutoff of LVEDP ≥ 13 mm Hg as optimal for predicting the primary outcome. Multivariable Cox regression demonstrated that LVEDP ≥ 13 mm Hg (adjusted hazard ratio, 4.00; P = .037) and postoperative right ventricle pressure 3/4 (adjusted hazard ratio, 21.75; P .001) were significantly associated with primary outcome, independent of age, weight, and diagnosis.Elevated preoperative LVEDP is a risk factor for suboptimal postoperative hemodynamic parameters and adverse outcome following BiV conversion from single-ventricle palliation.

Objectives. Guidewires used in pediatric catheterization are typically floppy, soft, or J-tipped, and are generally assumed to be atraumatic. A recent sentinel case suggested that such wires may cause clinically significant pulmonary artery (PA) injury. We sought to determine the incidence of wire-related PA injury as a cause of “idiopathic” airway bleeding (endobronchial blood) during interventional cardiac catheterization in patients with congenital heart disease. Design. The Children's Hospital Boston database of cardiac catheterizations was reviewed for adverse events (AEs) indicating possible PA injury occurring between September 2006 and August 2011. Procedure notes were reviewed, and when the clinical scenario was suggestive of wire injury or was not clear, relevant angiograms were reviewed. Results. One thousand forty-seven cases involving PA dilation were performed in the period of interest. Five cases of probable wire injury were identified, suggesting an incidence of approximately 0.5 per 100 cases. Of these five cases, trauma was judged due to floppy-tipped wires in two, soft-tipped wires in two, and a J-tipped wire in one. In three cases, the distal wire was looped such that the leading segment was stiffer than the wire tip. Clinical manifestations of wire injury comprised contrast within the airway, vessel aneurysm/tear, obstructive intimal flap, blood from the endotracheal tube, hemothorax, and wedge defect on lung scan. These injuries were relatively benign and did not result in instability or prolonged bleeding. Conclusions. Wire injury to the PAs is relatively uncommon, although possible with even floppy-tipped wires. The mechanism and implications of such injuries are markedly different than balloon-mediated vascular tears.

Background: Neonatal asphyxia can be complicated by myocardial dysfunction with secondary alterations in pulmonary and regional hemodynamics. Levosimendan is a calcium-sensitizing inotrope that may support cardiac output, but little is known regarding its differential hemodynamic effects in asphyxiated neonates. Methods: Mixed breed piglets (1–4 days old, weight 1.6–2.3 kg) were acutely instrumented. Normocapnic alveolar hypoxia (10–15% oxygen) was induced for 2 h, followed by reoxygenation with 100% (1 h) and then 21% oxygen (3 h). At 2 h of reoxygenation, after volume loading (Ringer’s lactate 10 ml/kg), either levosimendan (0.1 or 0.2 µg/kg/min) or D5W (placebo) was infused for 2 h in a blinded, block-randomized fashion (n = 7–8/group). The systemic, pulmonary and regional (carotid, superior mesenteric and renal) hemodynamics were compared. Results: At 0.1 and 0.2 µg/kg/min, levosimendan significantly increased cardiac output (121 and 123% of pretreatment, respectively) and heart rate, and decreased systemic vascular resistance without causing hypotension. Pulmonary arterial pressure and estimated pulmonary vascular resistance were significantly increased from pretreatment baseline in 0.1 but not 0.2 µg/kg/min levosimendan. Levosimendan infusion had no effects on regional hemodynamics. Myocardial efficiency but not oxygen consumption increased with 0.1 µg/kg/min levosimendan without significant effects on plasma troponin and myocardial lactate levels. Conclusions: In newborn piglets following hypoxia-reoxygenation injury, levosimendan improves cardiac output but has no marked effects in carotid, superior mesenteric and renal perfusion. It appears that various doses of levosimendan increase the cardiac output through different mechanisms. Further investigations are needed to examine the effectiveness of levosimendan as a cardiovascular supportive therapy either alone or in conjunction with other inotropes in asphyxiated neonates.

Introduction: Real time estimates of pulmonary (Qp) and systemic blood flow (Qs) could improve pediatric cardiac care. Current generation inert gas rebreathing (IGR) devices are safe, portable, and easy to use; can estimate Qp and Qs rapidly at the bedside; and can now be adapted for use in intubated patients. We compared IGR and two types of Fick Qp estimates, those using measured (FickM) and assumed (FickA) oxygen consumption (VO2) values, in mechanically ventilated pediatric cardiac patients with no shunt lesion or exclusive right-to-left shunt. Secondarily, we compared measured VO2 with assumed values and values back-calculated from the Fick equation (using measured saturations, hemoglobin and IGR Qp). Methods: In 18 intubated patients in the pediatric catheterization laboratory, the modified ventilator-compatible InnocorTM device was used to measure IGR Qp and breath-by-breath VO2; assumed VO2 was taken from LaFarge tables. Sampled pulmonary arterial and venous saturations were used to calculate FickM and FickA. Bland-Altman agreement and Spearman correlation were assessed for IGR Qp with FickA Qp and FickM Qp. Secondarily, agreement was analyzed between measured VO2, assumed VO2, and VO2 calculated from the Fick equation. Results: Subjects were aged 4-23 years, with a range of cardiac diagnoses. The figure shows Bland-Altman plots for Qp. Compared with FickA, IGR Qp had mean bias -0.9 L/min, 95% limits of agreement (=±1.96 SD) -2.8 to +1.0 L/min, and r=0.75. Compared with FickM, IGR Qp had mean bias -0.2 L/min, 95% limits of agreement -1.3 to +1.0 L/min, and r=0.90. Agreement of assumed and measured VO2 was poor (bias +23%, ±55%); measured VO2 agreed better with Fick calculated VO2 than assumed VO2. Conclusions: IGR Qp estimates agree well with Fick Qp estimates. This agreement improves when VO2 is measured, as assumed VO2 agrees poorly with measured VO2. IGR is an attractive option for bedside monitoring of Qp in intubated children.

Pulmonary vein stenosis (PVS) carries significant morbidity and mortality for affected children, and its management often requires multiple angioplasty procedures. PVS angioplasty can be complicated by systemic embolic events such as stroke, but incidence and risk factors are poorly understood. We reviewed pediatric catheterizations involving PVS angioplasty and/or stent placement performed at Boston Children’s Hospital between July 2005 and February 2014. A total of 406 cases were performed in 144 distinct patients. Patients underwent a median of two catheterizations, at median age 1 year and weight 6.9 kg. Eleven (2.7 %) catheterizations were complicated by clinically apparent systemic embolic events, comprising 10 strokes (one with associated hepatic embolism) and 1 renal infarct. Prevalence of clinically evident stroke among this cohort was 7.6 %. Using a prior (uncomplicated) catheterization to allow each patient to serve as their own control, we sought to identify potentially modifiable risk factors for systemic embolic events. Although this analysis was limited by low power, complicated and uncomplicated angioplasties did not appear to differ in case time, contrast dose, anticoagulation management, use of cutting balloons, number of catheter exchanges, or size of long sheath used. Significant non-embolic adverse events were common, occurring in 25 % of catheterizations. Systemic embolism appears to complicate PVS angioplasty at a rate much higher than that described for other congenital catheterizations. This risk may be inherent to the procedure rather than related to any modifiable or operator-dependent factors.

Acute kidney injury (AKI) is a predictor of outcomes in heterogeneous populations of children undergoing cardiac surgery. We investigated its causes and consequences in a cohort undergoing Fontan completion, hypothesizing that central venous pressure is independently associated with development of AKI.In this retrospective cohort study of patients undergoing Fontan (n = 211), univariable and multivariable analyses identified factors associated with AKI within 3 days of surgery. Secondary analyses identified factors associated with hospital length of stay, and examined effects of perioperative kidney injury on follow-up renal function.Acute kidney injury occurred in 42% of cases (n = 89), with the following independent risk factors: mean renal perfusion (mean arterial minus central venous) pressure on postoperative day zero (per mm Hg; adjusted odds ratio [AOR] 0.83; P.001); preoperative atrioventricular valve regurgitationmild (AOR 6.78; P = .02); bypass time (per 10 minutes, AOR 1.08; P = .04); peak inotrope score on postoperative day zero (per point, AOR 1.17; P.001); and preoperative pulmonary vascular resistance (per Wood unit, AOR 1.69; P = .04). Central venous pressure was not independently associated with AKI. Moderate and severe (but not mild) AKI were independently associated with prolonged hospital length of stay (adjusted hazard ratios, 0.56; P = .004, and .41; P = .006, respectively). Perioperative injury was not associated with longer-term renal dysfunction.Acute kidney injury is common after Fontan completion and has several potentially modifiable risk factors. Moderate-to-severe injury is associated with longer hospital length of stay but not with renal dysfunction at follow-up.

We study the repeated folding of a two-parameter family of quadrilaterals about their successively transformed diagonals by examining the evolution of the diagonal lengths. Successively mapped pairs of squared lengths lie on an elliptic curve on which folding acts as translation under the group law. We prove the rotation number attains all possible values and any value determines a unique curve in parameter space. For rational parameters we give an algorithm to determine if the folding map is periodic. This gives a partial explanation for the diversity and intricacy of the curves traced out by the paths of the vertices of the transformed quadrilaterals.

This paper summarizes, clarifies, and corrects some aspects of the variational velocity methodfor the detection of limit cycles. After definitions and statements of the most important theoremsassociated with this method, some aspects of the proof of the main theorem are corrected andreworked. An example from the original paper in Acta Appl. Math. 48 (1997),13–32, is then discussed and criticized. Finally, the limitations of this method are discussed,especially as it applies to systems involving multiple limit cycles (and therefore as it applies toHilbert’s XVIth Problem).

Pulmonary arteriovenous malformations (PAVMs) are thought to form as a result of exclusion of hepatic venous blood from part of the pulmonary circulation. Surgical arteriovenous (AV) fistula creation has demonstrated therapeutic potential to reverse PAVM formation. We sought to demonstrate the feasibility and safety of transcatheter AV fistula creation for this indication. Fluoroscopically guided puncture from the basilic vein into the brachial artery using a Brockenbrough needle and sharpened 0.014" wire created a tract between these vessels. After balloon dilation of the tract, a covered stent was deployed, resulting in a functioning brachial AV fistula. The procedure was technically successful, with no clinical complications at 4 months follow-up. Repeat diagnostic catheterization revealed marked improvement in systemic saturation and near-resolution of PAVMs in the pilot patient. This report suggests that transcatheter brachial arteriovenous fistula formation is technically feasible, and may be effective in managing PAVMs in select single-ventricle patients.

Objective To assess the feasibility and accuracy of inert gas rebreathing (IGR) pulmonary blood flow (Qp) estimation in mechanically ventilated pediatric patients, potentially providing real-time noninvasive estimates of cardiac output. Study design In mechanically ventilated patients in the pediatric catheterization laboratory, we compared IGR Qp with Qp estimates based upon the Fick equation using measured oxygen consumption (VO 2 ) (Fick True ); for context, we compared Fick True with a standard clinical short-cut, replacing measured with assumed VO 2 in the Fick equation (Fick LaFarge , Fick Lundell , Fick Seckeler ). IGR Qp and breath-by-breath VO 2 were measured using the Innocor device. Sampled pulmonary arterial and venous saturations and hemoglobin concentration were used for Fick calculations. Qp estimates were compared using Bland-Altman agreement and Spearman correlation. Results The final analysis included 18 patients aged 4-23 years with weight >15 kg. Compared with the reference Fick True , IGR Qp estimates correlated best and had the least systematic bias and narrowest 95% limits of agreement (results presented as mean bias ±95% limits of agreement): IGR −0.2 ± 1.1 L/min, r = 0.90; Fick LaFarge +0.7 ± 2.2 L/min, r = 0.80; Fick Lundell +1.6 ± 2.9 L/min, r = 0.83; Fick Seckeler +0.8 ± 2.5 L/min, r = 0.83. Conclusions IGR estimation of Qp is feasible in mechanically ventilated patients weighing >15 kg, and agreement with Fick True Qp estimates is better for IGR than for other Fick Qp estimates commonly used in pediatric catheterization. IGR is an attractive option for bedside monitoring of Qp in mechanically ventilated children.

Guidewires used in pediatric catheterization are typically floppy, soft, or J-tipped, and are generally assumed to be atraumatic. A recent sentinel case suggested that such wires may cause clinically significant pulmonary artery (PA) injury. We sought to determine the incidence of wire-related PA injury as a cause of "idiopathic" airway bleeding (endobronchial blood) during interventional cardiac catheterization in patients with congenital heart disease.The Children's Hospital Boston database of cardiac catheterizations was reviewed for adverse events (AEs) indicating possible PA injury occurring between September 2006 and August 2011. Procedure notes were reviewed, and when the clinical scenario was suggestive of wire injury or was not clear, relevant angiograms were reviewed.One thousand forty-seven cases involving PA dilation were performed in the period of interest. Five cases of probable wire injury were identified, suggesting an incidence of approximately 0.5 per 100 cases. Of these five cases, trauma was judged due to floppy-tipped wires in two, soft-tipped wires in two, and a J-tipped wire in one. In three cases, the distal wire was looped such that the leading segment was stiffer than the wire tip. Clinical manifestations of wire injury comprised contrast within the airway, vessel aneurysm/tear, obstructive intimal flap, blood from the endotracheal tube, hemothorax, and wedge defect on lung scan. These injuries were relatively benign and did not result in instability or prolonged bleeding.Wire injury to the PAs is relatively uncommon, although possible with even floppy-tipped wires. The mechanism and implications of such injuries are markedly different than balloon-mediated vascular tears.

Patients with congenital heart disease carry a high burden of arrhythmias and may pose special challenges when these arrhythmias are addressed invasively. We sought to describe our early experience with radiofrequency (RF) needle transseptal perforation to facilitate ablation procedures in this population.Retrospective chart review to identify all cases of attempted transseptal access with a commercial RF needle at Children's Hospital Boston between February 2007 and January 2010.A total of 10 patients had attempted RF transseptal perforation. Median age was 27 years. Five patients had undergone atrial switch procedures (Mustard/Senning), four had undergone Fontan operations, and one had atrial septal defect repair. The indication for left atrial access was mapping/ablation of atrial flutter in nine cases, and left-sided accessory pathway in one case. The RF needle was chosen primarily in eight of 10 cases, whereas in the remaining two cases RF was used only after failed attempts with a conventional Brockenbrough needle. Septal material was atrial muscle in five cases, pericardium in three, and synthetic fabric in two. In nine of 10 patients, RF transseptal perforation was successful, including both patients in whom a conventional needle had failed. There were no clinically significant complications.RF transseptal perforation can be an effective method of obtaining left atrial access for electrophysiologic procedures in patients with complex congenital heart disease, including cases where a conventional Brockenbrough needle has failed.

Fluconazole is an antifungal medication that has been reported to cause prolongation of the QT interval and Torsades de Pointes (TdP) ventricular tachycardia in adults. We describe the case of an 11-year-old child treated with fluconazole who developed ventricular arrhythmia culminating in TdP. We discuss the possible roles played by genetic and environmental factors in this child's rhythm disturbances. After briefly summarizing similar cases from the adult literature, we outline the putative mechanism by which fluconazole may cause arrhythmia. This case should alert pediatricians to the possible risks of fluconazole use, especially in the presence of electrolyte abnormalities, diuretic use, therapy with other pro-arrhythmic agents, or suspicion of congenital Long-QT Syndrome.