Background-MRI is increasingly used for anatomic assessment of aortic coarctation (CoA), but its ability to predict the transcatheter pressure gradient, considered the reference standard for hemodynamic severity, has not been studied in detail. This study evaluated the ability of MRI to distinguish between mild versus moderate and severe CoA as determined by cardiac catheterization. Methods and Results-The clinical, MRI, and catheterization data of 31 subjects referred for assessment of native or recurrent CoA were reviewed retrospectively. Patients were divided into 2 groups on the basis of peak coarctation gradient by catheterization: Ͻ20 mm Hg (nϭ12) and Ն20 mm Hg (nϭ19). Patients with cardiac index Ͻ2.2 L · min

As the population of adults with congenital heart disease continues to grow, so does the number of these patients with heart failure. Ventricular assist devices are underutilized in adults with congenital heart disease due to their complex anatomic arrangements and physiology. Advanced imaging techniques that may increase the utilization of mechanical circulatory support in this population must be explored. Three-dimensional printing offers individualized structural models that would enable pre-surgical planning of cannula and device placement in adults with congenital cardiac disease and heart failure who are candidates for such therapies. We present a review of relevant cardiac anomalies, cases in which such models could be utilized, and some background on the cost and procedure associated with this process.

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The method of cardiac magnetic resonance (CMR) three-dimensional (3D) image acquisition and post-processing which should be used to create optimal virtual models for 3D printing has not been studied systematically. Patients (n = 19) who had undergone CMR including both 3D balanced steady-state free precession (bSSFP) imaging and contrast-enhanced magnetic resonance angiography (MRA) were retrospectively identified. Post-processing for the creation of virtual 3D models involved using both myocardial (MS) and blood pool (BP) segmentation, resulting in four groups: Group 1-bSSFP/MS, Group 2-bSSFP/BP, Group 3-MRA/MS and Group 4-MRA/BP. The models created were assessed by two raters for overall quality (1-poor; 2-good; 3-excellent) and ability to identify predefined vessels (1-5: superior vena cava, inferior vena cava, main pulmonary artery, ascending aorta and at least one pulmonary vein). A total of 76 virtual models were created from 19 patient CMR datasets. The mean overall quality scores for Raters 1/2 were 1.63 ± 0.50/1.26 ± 0.45 for Group 1, 2.12 ± 0.50/2.26 ± 0.73 for Group 2, 1.74 ± 0.56/1.53 ± 0.61 for Group 3 and 2.26 ± 0.65/2.68 ± 0.48 for Group 4. The numbers of identified vessels for Raters 1/2 were 4.11 ± 1.32/4.05 ± 1.31 for Group 1, 4.90 ± 0.46/4.95 ± 0.23 for Group 2, 4.32 ± 1.00/4.47 ± 0.84 for Group 3 and 4.74 ± 0.56/4.63 ± 0.49 for Group 4. Models created using BP segmentation (Groups 2 and 4) received significantly higher ratings than those created using MS for both overall quality and number of vessels visualized (p < 0.05), regardless of the acquisition technique. There were no significant differences between Groups 1 and 3. The ratings for Raters 1 and 2 had good correlation for overall quality (ICC = 0.63) and excellent correlation for the total number of vessels visualized (ICC = 0.77). The intra-rater reliability was good for Rater A (ICC = 0.65). Three models were successfully printed on desktop 3D printers with good quality and accurate representation of the virtual 3D models. We recommend using BP segmentation with either MRA or bSSFP source datasets to create virtual 3D models for 3D printing. Desktop 3D printers can offer good quality printed models with accurate representation of anatomic detail.

D ouble-outlet right ventricle falls under the category of congenital heart disease known as conotruncal defects, which possess abnormal ventriculoarterial relationships.1 For complex cases, the surgeon must determine whether the left ventricle and one of the great arteries can be aligned using the ventricular septal defect to construct an unobstructed pathway or baffle, resulting in a 2-ventricle repair.2 Creation of the baffle can be complicated by anatomic obstructions because of prominent conal septum, straddling atrioventricular valve attachments, or location of the ventricular septal defect in the inlet septum, remote from any great artery. Three-dimensional (3D) printing has been applied in the management of many different congenital heart diseases. 3In this specific patient population, in whom communicating the complex intracardiac anatomy to the surgeon is so critical, the use of 3D modeling and printing is invaluable.We used this approach in a patient with dextrocardia, complex double-outlet right ventricle (S,L,A) 1 and supratricuspid ring. She underwent pulmonary artery banding in infancy and had been doing relatively well clinically; so that any further surgical intervention was deferred until she was 8 years old. Although she was growing well and required no medication, she had some dyspnea on exertion and had become progressively more desaturated with oxygen saturations in the low 80s. The patient underwent a cardiac MRI to better outline the anatomy (Figure 1). The 3D balanced steady state free precession images were used to create a 3D virtual model that allowed visualization of the intracardiac anatomy (Figure 2, left). The 3D stereolithography file was then printed (Projet 3500 HD Max; 3D systems, Rock Hill, SC) to create a physical model that allowed clear delineation of potential baffle pathways (Figure 2, right). The aorta, which was anterior to the pulmonary artery in this patient, was relatively far removed from the left ventricle, and the ventricular septal defect was subpulmonary. After assessment of the 3D intracardiac anatomy, it was decided that the patient would have a double-switch procedure. The right atrium was baffled to the right ventricle (left-sided), and the left ventricle (right-sided) was baffled, via the ventricular septal defect, to the pulmonary artery. An arterial switch was then performed to direct the deoxygenated blood to the pulmonary artery and the oxygenated blood to the aorta. There was an excellent correlation between the 3D model and the actual anatomy. She is doing well clinically 6 months post procedure.There are a wide range of applications for 3D printing technology in preprocedural planning for patients with cardiac pathology. In addition to simply demonstrating complex intracardiac anatomy, as in our patient, it also allows us the possibility to test an intervention. For example, our interventional colleagues can use a 3D printed left ventricular outflow tract for sizing before transcatheter aortic valve implantation or a model of the dilated right ventr...

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Our goal was to construct three-dimensional (3D) virtual models to allow simultaneous visualization of the ventricles, ventricular septal defect (VSD) and great arteries in patients with complex intracardiac anatomy to aid in surgical planning. We also sought to correlate measurements from the source cardiac magnetic resonance (CMR) image dataset and the 3D model. Complicated ventriculo-arterial relationships in patients with complex conotruncal malformations make preoperative assessment of possible repair pathways difficult. Patients were chosen with double outlet right ventricle for the complexity of intracardiac anatomy and potential for better delineation of anatomic spatial relationships. Virtual 3D models were generated from CMR 3D datasets. Measurements were made on the source CMR as well as the 3D model for the following structures: aortic diameter in orthogonal planes, VSD diameter in orthogonal planes and long axis of right ventricle. A total of six patients were identified for inclusion. The path from the ventricles to each respective outflow tract and the location of the VSD with respect to each great vessel was visualized clearly in all patients. Measurements on the virtual model showed excellent correlation with the source CMR when all measurements were included by Pearson coefficient, r = 0.99 as well as for each individual structure. Construction of virtual 3D models in patients with complex conotruncal defects from 3D CMR datasets allows for simultaneous visualization of anatomic relationships relevant for surgical repair. The availability of these models may allow for a more informed preoperative evaluation in these patients.

2, respectively, and was validated against an independent sample. The mean indexed LAV±SD for BSA≤1 m 2 and >1 m 2 is 31.5±5.5 mL and 26.0±4.2 mL, respectively, and was used to derive Z-scores. Conclusions-This