The use of autologous bone to reconstruct skull defects in pediatric patients after decompressive craniectomy is associated with a high incidence of bone resorption. The use of autologous bone should be reevaluated in light of the high rate of reoperation in this pediatric population.

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Background-ICD implants in children and patients with congenital heart disease are complicated by body size and anatomy. A variety of creative implant techniques have been utilized empirically in these groups on an ad hoc basis.

The Fontan operation places the systemic and pulmonary circulations in series, driven by a single ventricular chamber. It has become the treatment strategy of choice for palliating single-ventricle congenital heart disease. This anatomy engenders profound changes in physiology, affecting the cardiovascular and respiratory systems with direct implications for anesthetic and intensive care. The physical basis of these changes and their sequelae are reviewed.

Mortality in infants with Glenn physiology supported with ECMO is lower than that previously reported, but the incidence of neurologic injury is high. These data support use of ECMO in patients with Glenn physiology with refractory cardiopulmonary failure.

Mastering the technical skills required to perform pediatric cardiac valve surgery is challenging in part due to limited opportunity for practice. Transformation of 3D echocardiographic (echo) images of congenitally abnormal heart valves to realistic physical models could allow patient-specific simulation of surgical valve repair. We compared materials, processes, and costs for 3D printing and molding of patient-specific models for visualization and surgical simulation of congenitally abnormal heart valves. Pediatric atrioventricular valves (mitral, tricuspid, and common atrioventricular valve) were modeled from transthoracic 3D echo images using semi-automated methods implemented as custom modules in 3D Slicer. Valve models were then both 3D printed in soft materials and molded in silicone using 3D printed "negative" molds. Using pre-defined assessment criteria, valve models were evaluated by congenital cardiac surgeons to determine suitability for simulation. Surgeon assessment indicated that the molded valves had superior material properties for the purposes of simulation compared to directly printed valves (p < 0.01). Patient-specific, 3D echo-derived molded valves are a step toward realistic simulation of complex valve repairs but require more time and labor to create than directly printed models. Patient-specific simulation of valve repair in children using such models may be useful for surgical training and simulation of complex congenital cases.

Background Total subcutaneous implantable subcutaneous defibrillators are in development, but optimal electrode configurations are not known. Objective We used image-based finite element models (FEM) to predict the myocardial electric field generated during defibrillation shocks (pseudo-DFT) in a wide variety of reported and innovative subcutaneous electrode positions, to determine factors affecting optimal lead positions for subcutaneous ICDs (S-ICD). Methods An image-based FEM of an adult male was used to predict pseudo-DFTs across a wide range of technically feasible S-ICD electrode placements. Generator location, lead location, length, geometry and orientation, and spatial relation of electrodes to ventricular mass were systematically varied. Best electrode configurations were determined, and spatial factors contributing to low pseudo-DFTs were identified using regression and general linear models. Results 122 single-electrode/array configurations and 28 dual-electrode configurations were simulated. Pseudo-DFTs for single-electrode orientations ranged from 0.60 – 16.0 (mean 2.65 ± 2.48) times that predicted for the base case, an anterior posterior configuration recently tested clinically. 32/150 tested configurations (21%) had pseudo-DFT ratios ≤ 1, indicating the possibility of multiple novel, efficient, and clinically relevant orientations. Favorable alignment of lead-generator vector with ventricular myocardium and increased lead length were the most important factors correlated with pseudo-DFT, accounting for 70% of the predicted variation (R2=0.70, each factor p <0.05) in a combined general linear model in which parameter estimates were calculated for each factor. Conclusions Further exploration of novel and efficient electrode configurations may be of value in the development of the S-ICD technologies and implant procedure. FEM modeling suggests that the choice of configurations which maximizes shock vector alignment with the center of myocardial mass and use of longer leads is more likely to result in lower DFT.

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