Laura Olivieri

Three-Dimensional Printing of Intracardiac Defects from Three-Dimensional Echocardiographic Images: Feasibility and Relative Accuracy

BACKGROUND With the advent of three-dimensional (3D) printers and high-resolution cardiac imaging, rapid prototype constructions of congenital cardiac defects are now possible. Typically, source images for these models derive from higher resolution, cross-sectional cardiac imaging, such as cardiac magnetic resonance imaging or computed tomography. These imaging methods may involve intravenous contrast, sedation, and ionizing radiation. New echocardiographic transducers and advanced software and hardware have optimized 3D echocardiographic images for this purpose. Thus, the objectives of this study were to confirm the feasibility of creating cardiac models from 3D echocardiographic data and to assess accuracy by comparing 3D model measurements with conventional two-dimensional (2D) echocardiographic measurements of cardiac defects. METHODS Nine patients undergoing 3D echocardiography were identified (eight with ventricular septal defects, one with three periprosthetic aortic valve leaks). Raw echocardiographic image data were exported anonymously and converted to Digital Imaging and Communications in Medicine format. The image data were filtered for noise reduction, imported into segmentation software to create a 3D digital model, and printed. Measurements of the defects from the 3D model were compared with defect measurements from conventional 2D echocardiographic data. Meticulous care was taken to ensure identical measurement planes. RESULTS Long- and short-axis measurements of eight ventricular septal defects and three perivalvar leaks were obtained. Mean ± SD values for the 3D model measurements and conventional 2D echocardiographic measurements were 7.5 ± 6.3 and 7.1 ± 6.2 mm respectively (P = .20), indicating no significant differences between the standard 2D and 3D model measurements. The two groups were highly correlated, with a Pearson correlation coefficient of 0.988. The mean absolute error (2D - 3D) for each measurement was 0.4 ± 0.9 mm, indicating accuracy of the 3D model of <1 mm. CONCLUSIONS Three-dimensional printed models of echocardiographic data are technically feasible and may accurately reflect ventricular septal defect anatomy. Three-dimensional models derived from 3D echocardiographic data sets represent a new tool in procedural planning for children with congenital heart disease.

Utilizing three-dimensional printing technology to assess the feasibility of high-fidelity synthetic ventricular septal defect models for simulation in medical education

Background: The current educational approach for teaching congenital heart disease (CHD) anatomy to students involves instructional tools and techniques that have significant limitations. This study sought to assess the feasibility of utilizing present-day three-dimensional (3D) printing technology to create high-fidelity synthetic heart models with ventricular septal defect (VSD) lesions and applying these models to a novel, simulation-based educational curriculum for premedical and medical students. Methods: Archived, de-identified magnetic resonance images of five common VSD subtypes were obtained. These cardiac images were then segmented and built into 3D computer-aided design models using Mimics Innovation Suite software. An Objet500 Connex 3D printer was subsequently utilized to print a high-fidelity heart model for each VSD subtype. Next, a simulation-based educational curriculum using these heart models was developed and implemented in the instruction of 29 premedical and medical students. Assessment of this curriculum was undertaken with Likert-type questionnaires. Results: High-fidelity VSD models were successfully created utilizing magnetic resonance imaging data and 3D printing. Following instruction with these high-fidelity models, all students reported significant improvement in knowledge acquisition (P < .0001), knowledge reporting (P < .0001), and structural conceptualization (P < .0001) of VSDs. Conclusions: It is feasible to use present-day 3D printing technology to create high-fidelity heart models with complex intracardiac defects. Furthermore, this tool forms the foundation for an innovative, simulation-based educational approach to teach students about CHD and creates a novel opportunity to stimulate their interest in this field.

3D heart model guides complex stent angioplasty of pulmonary venous baffle obstruction in a Mustard repair of D-TGA

a Childrens National Medical Center, Division of Cardiology, 111 Michigan Avenue NW Suite W3-200, Washington, DC 20010, United States b Childrens National Medical Center, Sheik Zayed Institute for Pediatric Surgical Innovation, 111 Michigan Avenue NW, Room M777, Washington, DC 20010, United States c National Institutes of Health, National Heart, Lung and Blood Institute, Advanced Cardiovascular Imaging Laboratory, Building 10, B1D416, Bethesda, MD 20892, United States

Coronary artery Z score regression equations and calculators derived from a large heterogeneous population of children undergoing echocardiography.

BACKGROUND Clinical decision making in Kawasaki disease relies on measurements of the coronary arteries obtained by 2-dimensional echocardiography. Z scores relating measured values to independent variables are invaluable in ensuring the accurate and consistent treatment of patients with Kawasaki disease. METHODS The right coronary artery (RCA), left main coronary artery (LMCA), and left anterior descending (LAD) coronary artery were measured in 432 normal digital echocardiograms from a heterogeneous population of normal subjects aged 0 to 20 years. Linear regression analyses were performed relating the measurements to various functions of independent variables, including body surface area (BSA), height, and height. The adjusted R(2) and mean square error values were compared for each of the models, and the best model was chosen to create a Z score calculator. RESULTS Using the model ln(measurement) = beta(1) + beta(2) x ln(BSA), the adjusted R(2) values were 0.638, 0.702, and 0.708 for the RCA, LMCA, and LAD coronary artery models, respectively, with mean square error < 0.0402. CONCLUSION The calculation of accurate Z scores for coronary artery measurements in children can be accomplished using the Z-score calculator.

Bicuspid aortic valve and aortic coarctation are linked to deletion of the X chromosome short arm in Turner syndrome

Background Congenital heart disease (CHD) is a cardinal feature of X chromosome monosomy, or Turner syndrome (TS). Haploinsufficiency for gene(s) located on Xp have been implicated in the short stature characteristic of the syndrome, but the chromosomal region related to the CHD phenotype has not been established. Design We used cardiac MRI to diagnose cardiovascular abnormalities in four non-mosaic karyotype groups based on 50-metaphase analyses: 45,X (n=152); 46,X,del(Xp) (n=15); 46,X,del(Xq) (n=4); and 46,X,i(Xq) (n=14) from peripheral blood cells. Results Bicuspid aortic valves (BAV) were found in 52/152 (34%) 45,X study subjects and aortic coarctation (COA) in 19/152 (12.5%). Isolated anomalous pulmonary veins (APV) were detected in 15/152 (10%) for the 45,X study group, and this defect was not correlated with the presence of BAV or COA. BAVs were present in 28.6% of subjects with Xp deletions and COA in 6.7%. APV were not found in subjects with Xp deletions. The most distal break associated with the BAV/COA trait was at cytologic band Xp11.4 and ChrX:41,500 000. One of 14 subjects (7%) with the 46,X,i(Xq) karyotype had a BAV and no cases of COA or APV were found in this group. No cardiovascular defects were found among four patients with Xq deletions. Conclusions The high prevalence of BAV and COA in subjects missing only the X chromosome short arm indicates that haploinsufficiency for Xp genes contributes to abnormal aortic valve and aortic arch development in TS.

Spectrum of Aortic Valve Abnormalities Associated With Aortic Dilation Across Age Groups in Turner Syndrome

Background—Congenital aortic valve fusion is associated with aortic dilation, aneurysm, and rupture in girls and women with Turner syndrome. Our objective was to characterize aortic valve structure in subjects with Turner syndrome and to determine the prevalence of aortic dilation and valve dysfunction associated with different types of aortic valves. Methods and Results—The aortic valve and thoracic aorta were characterized by cardiovascular MRI in 208 subjects with Turner syndrome in an institutional review board–approved natural history study. Echocardiography was used to measure peak velocities across the aortic valve and the degree of aortic regurgitation. Four distinct valve morphologies were identified: tricuspid aortic valve, 64% (n=133); partially fused aortic valve, 12% (n=25); bicuspid aortic valve, 23% (n=47); and unicuspid aortic valve, 1% (n=3). Age and body surface area were similar in the 4 valve morphology groups. There was a significant trend, independent of age, toward larger body surface area–indexed ascending aortic diameters with increasing valve fusion. Ascending aortic diameters were (mean±SD) 16.9±3.3, 18.3±3.3, and 19.8±3.9 mm/m2 (P<0.0001) for tricuspid aortic valve, partially fused aortic valve, and bicuspid aortic valve+unicuspid aortic valve, respectively. Partially fused aortic valve, bicuspid aortic valve, and unicuspid aortic valve were significantly associated with mild aortic regurgitation and elevated peak velocities across the aortic valve. Conclusions—Aortic valve abnormalities in Turner syndrome occur with a spectrum of severity and are associated with aortic root dilation across age groups. Partial fusion of the aortic valve, traditionally regarded as an acquired valve problem, had an equal age distribution and was associated with an increased ascending aortic diameters.

“Just-In-Time” Simulation Training Using 3-D Printed Cardiac Models After Congenital Cardiac Surgery

Background: High-fidelity simulation using patient-specific three-dimensional (3D) models may be effective in facilitating pediatric cardiac intensive care unit (PCICU) provider training for clinical management of congenital cardiac surgery patients. Methods: The 3D-printed heart models were rendered from preoperative cross-sectional cardiac imaging for 10 patients undergoing congenital cardiac surgery. Immediately following surgical repair, a congenital cardiac surgeon and an intensive care physician conducted a simulation training session regarding postoperative care utilizing the patient-specific 3D model for the PCICU team. After the simulation, Likert-type 0 to 10 scale questionnaire assessed participant perception of impact of the training session. Results: Seventy clinicians participated in training sessions, including 22 physicians, 38 nurses, and 10 ancillary care providers. Average response to whether 3D models were more helpful than standard hand off was 8.4 of 10. Questions regarding enhancement of understanding and clinical ability received average responses of 9.0 or greater, and 90% of participants scored 8 of 10 or higher. Nurses scored significantly higher than other clinicians on self-reported familiarity with the surgery (7.1 vs 5.8; P = .04), clinical management ability (8.6 vs 7.7; P = .02), and ability enhancement (9.5 vs 8.7; P = .02). Compared to physicians, nurses and ancillary providers were more likely to consider 3D models more helpful than standard hand off (8.7 vs 7.7; P = .05). Higher case complexity predicted greater enhancement of understanding of surgery (P = .04). Conclusion: The 3D heart models can be used to enhance congenital cardiac critical care via simulation training of multidisciplinary intensive care teams. Benefit may be dependent on provider type and case complexity.

Impact of Three-Dimensional Printing on the Study and Treatment of Congenital Heart Disease.

Three-dimensional (3D) printing technology allows for the translation of a 2-dimensional medical imaging study into a physical replica of a patient’s individual anatomy. 3D printed models can facilitate a deeper understanding of complex patient anatomy and can aid in presurgical decision-making.1 Although there are 3D printing case reports in almost every subspecialty of medicine to date, the rate of adoption in the field of congenital heart disease (CHD) is particularly advanced.2,3 This is due, in no small part, to the fact that the heart is a hollow organ, which makes it a perfect substrate for 3D printing. More importantly, medical decision-making in CHD is informed by assessment of the anatomic morphology of the heart because cardiac pathology is a direct manifestation of the underlying 3D structure. Reports on the application of 3D printing in the study and treatment of CHD are accumulating rapidly; these studies cover uses, including advanced visualization, surgical planning, and education.4 Individual case reports and small studies indicate the potential to improve patient outcomes using patient-specific 3D models. There is a growing body of literature that demonstrates the value of 3D models in decision-making,5 procedural planning,5–7 and postoperative care simulation.8,9 Two specific cases are illustrated for the reader’s interest in Figures 1 and 2. Figure 1. After surgical repair of a superior sinus venosus defect and anomalous pulmonary venous drainage, a 4-year-old girl was found to have a long-segment stenosis of the superior vena cava (SVC) as it entered the right atrium, anterior to the right upper pulmonary venous baffle. A 3-dimensional (3D) printed model created from the magnetic resonance imaging (MRI) data more clearly demonstrated the relationship of the SVC stenosis to the right upper pulmonary vein baffle, giving operators the confidence to proceed with …

Usage of 3D models of tetralogy of Fallot for medical education: impact on learning congenital heart disease

BackgroundCongenital heart disease (CHD) is the most common human birth defect, and clinicians need to understand the anatomy to effectively care for patients with CHD. However, standard two-dimensional (2D) display methods do not adequately carry the critical spatial information to reflect CHD anatomy. Three-dimensional (3D) models may be useful in improving the understanding of CHD, without requiring a mastery of cardiac imaging. The study aimed to evaluate the impact of 3D models on how pediatric residents understand and learn about tetralogy of Fallot following a teaching session.MethodsPediatric residents rotating through an inpatient Cardiology rotation were recruited. The sessions were randomized into using either conventional 2D drawings of tetralogy of Fallot or physical 3D models printed from 3D cardiac imaging data sets (cardiac MR, CT, and 3D echocardiogram). Knowledge acquisition was measured by comparing pre-session and post-session knowledge test scores. Learner satisfaction and self-efficacy ratings were measured with questionnaires filled out by the residents after the teaching sessions. Comparisons between the test scores, learner satisfaction and self-efficacy questionnaires for the two groups were assessed with paired t-test.ResultsThirty-five pediatric residents enrolled into the study, with no significant differences in background characteristics, including previous clinical exposure to tetralogy of Fallot. The 2D image group (n = 17) and 3D model group (n = 18) demonstrated similar knowledge acquisition in post-test scores. Residents who were taught with 3D models gave a higher composite learner satisfaction scores (P = 0.03). The 3D model group also had higher self-efficacy aggregate scores, but the difference was not statistically significant (P = 0.39).ConclusionPhysical 3D models enhance resident education around the topic of tetralogy of Fallot by improving learner satisfaction. Future studies should examine the impact of models on teaching CHD that are more complex and elaborate.

Hypoplastic left heart syndrome with intact atrial septum sequelae of left atrial hypertension in utero.

![Figure][1] [![Graphic][3] ][3][![Graphic][4] ][4][![Graphic][5] ][5] A fetus diagnosed with hypoplastic left heart syndrome and intact atrial septum with severe left atrial (LA) and pulmonary venous hypertension ( A and B , [Online Video 1][5]) was delivered at 38 weeks