Ventricular Anatomy Research Articles

Comparative Anatomical Study on Operability in Surgical Approaches to the Anterior Part of the Third Ventricle

Surgery of the third ventricle still represents a challenge in modern neurosurgery. To optimize the surgical planning, some aspects, related to ventricular anatomy, have to be taken into consideration. An operability score could represent a preoperative tool to evaluate these variables to choose a tailored surgical approach. We compared the transcallosal transforaminal approach and the combined interhemispheric subcommissural translamina terminalis approach (CISTA) to the anterior part of the third ventricle, applying the operability score. Compared with the transcallosal transforaminal approach, the CISTA provides a statistically significant improvement in terms of depth of surgical field, surgical angle of attack, and maneuverability arc considering as 4 approach-related critical structures: the optic chiasm (P value: <0.0001, <0.0001, <0.0001, respectively), the anterior commissure (P value: <0.0001, <0.0001, <0.0001 respectively), the tuber cinereum (P value: <0.0001, 0.0224, 0.0173), and the interthalamic adhesion (P value: 0.2917, <0.0001, <0.0001 respectively). Tumors originating from the anterosuperior part of the third ventricle can be easily approached through a transcallosal transforaminal route, whereas lesions arising from the anteroinferior portion of the third ventricle might be safely and effectively approached through the CISTA.

Variable Myocardial Response to Load Stresses in Infants with Single Left Ventricular Anatomy: Influence of Initial Physiology and Surgical Palliative Strategy.

Initial surgical strategies in neonates with single left ventricular (LV) anatomy vary based on adequacy of pulmonary and systemic blood flow. Differing myocardial responses to these strategies, as reflected in indices of systolic function, ventricular size, and mass have not been well defined. We sought to evaluate single LV myocardial response to varied physiology and initial palliation and determine whether the response is consistent and predictable. Infants with single LV physiology were divided based on neonatal palliation: no palliation/PA band (NO); BT shunt only (BT); or Norwood procedure (NP). Echo measures were obtained at presentation, early post-bidirectional Glenn (BDG), late post-BDG follow-up, and post-Fontan procedure. Measures included ejection fraction, LV mass indexed to height2.7 and end diastolic volume indexed to body surface area, and mass/volume ratio. The cohort included 38 children (13 NO, 13 BT, 12 NP). Ejection fraction was similar but depressed in all groups at all stages. LV mass was higher in the NP group than the BT group at early post-BDG (p=0.03) and higher than both BT and NO groups (p<0.01) at late post-BDG, but the difference was resolved by post-Fontan follow-up. The NP group had the most remarkable remodeling in LV size from BDG to Fontan, suggesting that volume unloading is most valuable in this subgroup. Ventricular remodeling can be identified by echocardiography in children with single LV physiology, despite variable initial surgical palliative strategies. Importantly, these initial surgical strategies do not result in significant differences after Fontan palliation during early childhood.

Echocardiography in Pregnancy: Part 2.

The prevalence of pregnant women with cardiovascular heart disease is increasing. Transthoracic echocardiography is safe during pregnancy, and it is an important diagnostic tool in pregnant women with established heart disease in order to monitor ventricular and valvular anatomy and function. In addition, it can be used to delineate cardiac anatomy in complex congenital heart disease and help stratify maternal risk during pregnancy. This review will focus on the use of echocardiography in the diagnosis and management of pregnant women with common congenital lesions and with prosthetic valves.

Patient independent representation of the detailed cardiac ventricular anatomy.

Reparameterization of surfaces is a widely used tool in computer graphics known mostly from the remeshing algorithms. Recently, the surface reparameterization techniques started to gain popularity in the field of medical imaging, but mostly for convenient 2D visualization of the information initially represented on 3D surfaces (e.g. continuous bulls-eye plot). However, by consistently mapping the 3D information to the same 2D domain, surface reparameterization techniques allow us to put into correspondence anatomical shapes of inherently different geometry. In this paper, we propose a method for anatomical parameterization of cardiac ventricular anatomies that include myocardium, trabeculations, tendons and papillary muscles. The proposed method utilizes a quasi-conformal flattening of the myocardial surfaces of the left and right cardiac ventricles and extending it to cover the interior of the cavities using the local coordinates given by the solution of the Laplace's equation. Subsequently, we define a geometry independent representation for the detailed cardiac left and right ventricular anatomies that can be used for convenient visualization and statistical analysis of the trabeculations in a population. Lastly we show how it can be used for mapping the detailed cardiac anatomy between different hearts, which is of considerable interest for detailed cardiac computational models or shape atlases.

Assessment of the right ventricular anatomy and function by advanced echocardiography: pathological and physiological insights

Accurate assessment of right ventricular geometry and function is of high clinical importance. However, several limitations have to be taken into consideration if using conventional echocardiographic parameters. Advanced echocardiographic techniques, such as speckle-tracking analysis or 3D echocardiography are reliable and simple tools providing a cost-effective and non-invasive alternative of current modalities used to characterize the right ventricle. There is a growing interest in the diagnostic and prognostic value of these methods regarding pathological (right ventricular infarction, pulmonary hypertension, arrhythmogenic right ventricular dysplasia, follow-up of heart transplantation) and even physiological (athlete's heart) alterations of the right ventricle. Orv. Hetil., 2016, 157(29), 1139-1146.

Electrocardiographic Left Ventricular Hypertrophy as a Predictor of Cardiovascular Disease Independent of Left Ventricular Anatomy in Subjects Aged ≥65 Years

Left ventricular hypertrophy (LVH) diagnosed by electrocardiography (ECG-LVH) and echocardiography (echo-LVH) are independently associated with an increased risk of cardiovascular disease (CVD) events. However, it is unknown if ECG-LVH retains its predictive properties independent of LV anatomy. We compared the risk of CVD associated with ECG-LVH and echo-LVH in 4,076 participants (41% men, 86% white) from the Cardiovascular Health Study, who were free of baseline CVD. ECG-LVH was defined with Minnesota ECG Classification criteria from baseline ECG data. Echo-LVH was defined by gender-specific LV mass values normalized to body surface area (male: >102g/m(2); female: >88g/m(2)). ECG-LVH was detected in 144 participants (3.5%) and echo-LVH in 430 participants (11%). Over a median follow-up of 10.6years, 2,274 CVD events occurred. In a multivariate Cox regression analysis adjusted for common CVD risk factors, ECG-LVH (hazard ratio [HR] 1.84, 95% CI 1.51 to 2.24) and echo-LVH (HR 1.35, 95% CI 1.19 to 1.54) were associated with an increased risk for CVD events. The association between ECG-LVH and CVD events was not substantively altered with further adjustment for echo-LVH (HR 1.76, 95% CI 1.45 to 2.15). In conclusion, the association of ECG-LVH with CVD events is not dependent on echo-LVH. This finding provides support to the concept that ECG-LVH is an electrophysiological marker with predictive properties independent of LV anatomy.

Abstract P231: Electrocardiographic Versus Echocardiographic Left Ventricular Hypertrophy as a Predictor of Cardiovascular Disease Events in the General Population

Introduction: It is uncertain whether left ventricular hypertrophy (LVH) detected by the electrocardiogram (ECG) is able to be used as an alternative to LVH detected by imaging in population studies. Aim: We compared the risk of cardiovascular disease (CVD) associated with LVH as measured by Minnesota ECG classification (ECG-LVH), the most common ECG classification in population studies, with LVH detected by echocardiography, the most common tool to estimate left ventricular mass in clinical practice. Methods: This analysis included 4,076 participants (41% male, 86% white), aged 65 years or older from the Cardiovascular Health Study who were free of CVD at the time of enrollment. ECG-LVH was defined by the Minnesota ECG Classification criteria from baseline ECG data that were read centrally. Echocardiographic LVH (echo-LVH) was defined as left ventricular mass &gt;95th percentile using sex-specific cut-points. Results: ECG-LVH was detected in 144 (3.5%) participants and echo-LVH in 199 (4.9%) participants. Over a mean follow-up of 10.6 years, a total of 2,274 CVD events occurred. In a multivariate Cox regression analysis adjusted for age, sex, race, education, income, body mass index, HDL-cholesterol, total-cholesterol, smoking status, systolic blood pressure, diabetes, aspirin and blood pressure lowering drugs, the risk of CVD events associated with ECG-LVH (HR=1.84, 95% CI=1.51, 2.24) was higher than that associated with echo-LVH (HR=1.35, 95% CI 1.12, 1.62). The association between ECG-LVH and CVD events was not substantively altered with further adjustment for echo-LVH (HR=1.81, 95% CI=1.49, 2.21). Conclusion: The association of ECG-LVH with CVD events is not dependent on echo-LVH and provides additional support to the concept that ECG-LVH is an electrophysiologic marker with predictive properties independent of left ventricular anatomy.

Right Ventricular Anatomy Can Accommodate Multiple Micra Transcatheter Pacemakers.

BackgroundThe introduction of transcatheter pacemaker technology has the potential to significantly reduce if not eliminate a number of complications associated with a traditional leaded pacing system. However, this technology raises new questions regarding how to manage the device at end of service, the number of devices the right ventricle (RV) can accommodate, and what patient age is appropriate for this therapy. In this study, six human cadaver hearts and one reanimated human heart (not deemed viable for transplant) were each implanted with three Micra devices in traditional pacing locations via fluoroscopic imaging.MethodsA total of six human cadaver hearts were obtained from the University of Minnesota Anatomy Bequest Program; the seventh heart was a heart not deemed viable for transplant obtained from LifeSource and then reanimated using Visible Heart® methodologies. Each heart was implanted with multiple Micras using imaging and proper delivery tools; in these, the right ventricular volumes were measured and recorded. The hearts were subsequently dissected to view the right ventricular anatomies and the positions and spacing between devices.ResultsMultiple Micra devices could be placed in each heart in traditional, clinically accepted pacing implant locations within the RV and in each case without physical device interactions. This was true even in a human heart considered to be relatively small.ConclusionsAlthough this technology is new, it was demonstrated here that within the human heart's RV, three Micra devices could be accommodated within traditional pacing locations: with the potential in some, for even more.

Neurosurgical training with simulators: a novel neuroendoscopy model.

The aim of this study is to present a novel neuroendoscopy simulation model in live animals, with the objective of enhancing patient safety with realistic surgical training. A simulation model using live Wistar rats was designed after the approval of the Institutional Committee for the Care and Use of Laboratory Animals. Under anesthesia, a hydroperitoneum was created in order to simulate a cavity with mesenteric membranes and vessels, viscera, and a solid and bleeding tumor (the liver) floating in a liquid environment. For validation purposes, we evaluated trainees' basal and final skills for each neuroendoscopic procedure, and we also acknowledged trainees' and instructors' opinion on the model's realism. This model is simple and low cost effective for complete and real-life training in neuroendoscopy, with the possibility of performing all the basic and advanced endoscopic procedures, such as endoscopic exploration, membrane fenestration, vessel coagulation, hematoma evacuation, and endoscopic tumor biopsy and resection using a ventricular neuroendoscopy set. Although the model does not represent human ventricular anatomy, a reliable simulation is possible in real living tissue in a liquid environment. Trainees' skills improvements were notorious. Minimally invasive endoscopic techniques require specific training. Simulation training can improve and accelerate the learning curve. The presented training model allows simulating the different neuroendoscopic procedures. We believe that due to its practical possibilities, its simplicity, low cost, reproducibility, and reality, being live animal tissue, it can be considered a fundamental model within a complete training program on neuroendoscopy.

A recommended workflow methodology in the creation of an educational and training application incorporating a digital reconstruction of the cerebral ventricular system and cerebrospinal fluid circulation to aid anatomical understanding.

BackgroundThe use of computer-aided learning in education can be advantageous, especially when interactive three-dimensional (3D) models are used to aid learning of complex 3D structures. The anatomy of the ventricular system of the brain is difficult to fully understand as it is seldom seen in 3D, as is the flow of cerebrospinal fluid (CSF). This article outlines a workflow for the creation of an interactive training tool for the cerebral ventricular system, an educationally challenging area of anatomy. This outline is based on the use of widely available computer software packages.MethodsUsing MR images of the cerebral ventricular system and several widely available commercial and free software packages, the techniques of 3D modelling, texturing, sculpting, image editing and animations were combined to create a workflow in the creation of an interactive educational and training tool. This was focussed on cerebral ventricular system anatomy, and the flow of cerebrospinal fluid.ResultsWe have successfully created a robust methodology by using key software packages in the creation of an interactive education and training tool. This has resulted in an application being developed which details the anatomy of the ventricular system, and flow of cerebrospinal fluid using an anatomically accurate 3D model. In addition to this, our established workflow pattern presented here also shows how tutorials, animations and self-assessment tools can also be embedded into the training application.ConclusionsThrough our creation of an established workflow in the generation of educational and training material for demonstrating cerebral ventricular anatomy and flow of cerebrospinal fluid, it has enormous potential to be adopted into student training in this field. With the digital age advancing rapidly, this has the potential to be used as an innovative tool alongside other methodologies for the training of future healthcare practitioners and scientists. This workflow could be used in the creation of other tools, which could be developed for use not only on desktop and laptop computers but also smartphones, tablets and fully immersive stereoscopic environments. It also could form the basis on which to build surgical simulations enhanced with haptic interaction.

Left Ventricular Anatomy and Geometry by 64-slice Multi-Detector Computed Tomography in Patients with Low Left Ventricular Function

Left Ventricular Anatomy and Geometry by 64-slice Multi-Detector Computed Tomography in Patients with Low Left Ventricular Function

A Novel Class of Human Cardiac Stem Cells.

Following the recognition that hematopoietic stem cells improve the outcome of myocardial infarction in animal models, bone marrow mononuclear cells, CD34-positive cells, and mesenchymal stromal cells have been introduced clinically. The intracoronary or intramyocardial injection of these cell classes has been shown to be safe and to produce a modest but significant enhancement in systolic function. However, the identification of resident cardiac stem cells in the human heart (hCSCs) has created great expectation concerning the potential implementation of this category of autologous cells for the management of the human disease. Although phase 1 clinical trials have been conducted with encouraging results, the search for the most powerful hCSC for myocardial regeneration is in its infancy. This manuscript discusses the efforts performed in our laboratory to characterize the critical biological variables that define the growth reserve of hCSCs. Based on the theory of the immortal DNA template, we propose that stem cells retaining the old DNA represent 1 of the most powerful cells for myocardial regeneration. Similarly, the expression of insulin-like growth factor-1 receptors in hCSCs recognizes a cell phenotype with superior replicating reserve. However, the impressive recovery in ventricular hemodynamics and anatomy mediated by clonal hCSCs carrying the "mother" DNA underscores the clinical relevance of this hCSC class for the treatment of human heart failure.

Tei Index in a Sample of Patients with Ankylosing Spondylitis

Background and objectives: Ankylosing spondylitis (AS) is an inflammatory disease of immunological origin which has been correlated with higher cardiovascular risk. Although the risk factors are not clear, many cardiac alterations have been described, such as conduction disturbances, coronary heart disease, aortic root dilation, cardiac valve alterations, and ventricular diastolic dysfunction. The objective of this study was to evaluate echocardiographic findings in AS patients who were asymptomatic for cardiac disorders, and to compare them with findings from healthy subjects. Materials and methods: This study compared echocardiographic findings for 22 patients diagnosed with AS who had no previous cardiac abnormalities and 22 healthy subjects. We evaluated the cardiac cavities, left ventricular mass index, indices of systolic and diastolic ventricular function, the function and anatomy of the heart valves, and the myocardial performance index. Some of these measurements were correlated with disease duration and BASDAI (Bath Ankylosing Spondylitis Disease Activity Index). Results: There was no statistical difference between groups with regards to the size of cardiac chambers, ventricular mass index, and relative thickness of the ventricular wall. As for the ejection fraction, individuals in the AS group had lower levels for this parameter (p=0.02). The myocardial performance index (Tei index), considering TEI ≥ 0.44 as abnormal, was altered in 31.82% of the patient group, while no patient in the control group had an altered Tei index (p=0.009), reflecting poorer ventricular performance in patients with AS.

Endoscopic intracranial surgery enhanced by electromagnetic-guided neuronavigation in children.

Navigated intracranial endoscopy with conventional technique usually requires sharp head fixation. In children, especially in those younger than 1 year of age and in older children with thin skulls due to chronic hydrocephalus, sharp head fixation is not possible. Here, we studied the feasibility, safety, and accuracy of electromagnetic (EM)-navigated endoscopy in a series of children, obviating the need of sharp head fixation. Seventeen children (ten boys, seven girls) between 12 days and 16.8 years (mean age 4.3 years; median 14 months) underwent EM-navigated intracranial endoscopic surgery based on 3D MR imaging of the head. Inclusion criteria for the study were intraventricular cysts, arachnoid cysts, aqueduct stenosis for endoscopic third ventriculostomy (ETV) with distorted ventricular anatomy, the need of biopsy in intraventricular tumors, and multiloculated hydrocephalus. A total of 22 endoscopic procedures were performed. Patients were registered for navigation by surface rendering in the supine position. After confirming accuracy, they were repositioned for endoscopic surgery with the head fixed slightly on a horseshoe headholder. EM navigation was performed using a flexible stylet introduced into the working channel of a rigid endoscope. Neuronavigation accuracy was checked for deviations measured in millimeters on screenshots after the referencing procedure and during surgery in the coronal (z = vertical), axial (x = mediolateral), and sagittal (y = anteroposterior) planes. EM-navigated endoscopy was feasible and safe. In all 17 patients, the aim of endoscopic surgery was achieved, except in one case in which a hemorrhage occurred, blurring visibility, and we proceeded with open surgery without complications for the patient. Navigation accuracy for extracranial markers such as the tragus, bregma, and nasion ranged between 1 and 2.5 mm. Accuracy for fixed anatomical structures like the optic nerve or the carotid artery varied between 2 and 4 mm, while there was a broader variance of accuracy at the target point of the cyst itself ranging between 2 and 9 mm. EM-navigated endoscopy in children is a safe and useful technique enhancing endoscopic intracranial surgery and obviating the need of sharp head fixation. It is a good alternative to the common opto-electric navigation system in this age group.

9 3D transthoracic echocardiography to assess ventricular septal defect anatomy and severity

9 3D transthoracic echocardiography to assess ventricular septal defect anatomy and severity

0355 : 3D transthoracic echocardiography to assess ventricular septal defect anatomy and severity

The pathophysiology of Ventricular Septal Defect (VSD) is determined by the size of the defect and the state of the pulmonary vascular resistance. We assessed the morphology of VSD using 3D transthoracic echocardiography (3D-TTE) and the ability to estimate the pathophysiology. 48 children with isolated unique muscular (77%) and membranous VSD (23%) were included. Severity of the VSD was rated according to their pathophysiology. (Type 1: minor left-to-right (L-R) shunt; 2a: significant L-R shunt (left ventricular end diastolic diameter (LVEDD) Z-score >2); 2b: VSD associated with pulmonary hypertension). 3D VSD measurements were obtained after a multi-planar reconstruction of a TTE 3D full volume (X5-1 or X7-2 matrix probes, ie33, Philips). Diagnosis properties of the ratio of 3D VSD area to aortic annulus area (3DA/AAA), 3D VSD area to body surface area (3DA/BSA) and 2Dmax diameter to BSA (2DD/BSA) were compared. Median age was 8.5 month-old (min 1 max 123). LVEDD Zscore was>2 in 19 children (40%), (12 (25%) had pulmonary hypertension). 3DVSD systolic area, 3D and 2D max. diameters were correlated with LVEDD. (r=0.71, r=0.52, r=0.55, p<0.05). Systolo-diastolic variation of 3D VSD area was higher in muscular than in membranous VSD (Median 54%vs27%, p=0.0001). VSD were asymmetric with a mean ratio of maximal to minimal 3D diameters of 2.1±1.3 in membranous VSD and 3.2±1.5 in muscular VSD (p=0.01). VSD severity was correlated with LVEDD Z-score, 3DA/AAA and 3DA/BSA ratio (r=0.52, r=0.63, r=0.60, p<0.05), but not with the 2DD/BSA ratio. Ability to diagnose type 2b VSD was higher with the 3DA/AAA or 3DA/BSA ratio than the 2D/BSA ratio (ROC area 0.97 and 0.96 vs 0.85). A 3DA/AAA ratio>0.39 has a sensitivity of 92% and a specificity of 97% to diagnose a 2b-VSD. 3D-TTE allows a morphological and a quantitative assessment of muscular and membranous VSD. The 3DA/AAA ratio is an accurate diagnostic tool to assess the pathophysiology of the VSD.

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

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. 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. 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. 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.

Assessment of myocardial blood flow, viability and diffuse fibrosis in patients after arterial switch and ross operation with magnetic resonance imaging

Background Coronary artery reimplantation is crucial step during the arterial switch (ASO) and Ross operation. Mortality and long-term outcome after the operation mainly depend on the patency and function of the reimplanted coronary arteries due to risk of stenosis, stretching, or occlusion. Cardiovascular magnetic resonance (CMR) imaging has emerged as a promising diagnostic tool for the evaluation of children heart. We utilized advanced CMR methods to perform a noninvasive assessment of myocardial blood flow, viability, function and diffuse fibrosis in patients after ASO and Ross operation to guide further therapy and for a better understanding of the microcirculation. Methods MRI first-pass perfusion imaging (0.03 mmol/kg GdDTPA; TR/TE/a=2.6/1.1/20°) was performed in 36 patients (age, 15.75±10.94 yrs; transposition of the great arteries post arterial switch operation n=25, post Ross operation for the treatment of aortic valve disease n= 11) and in 10 age matched healthy controls. Myocardial blood flow (ml/g/min) was calculated in 6 LV segments per slice (2-3 slices/pt). Quantitative blood flow at rest and stress (Adenosin 140 µg/kg/min) was derived from signal intensity curves by model independent deconvolution. Late enhancement studies (Gd 0.1 mmol/kg) using T1 weighted inversion recovery sequences were performed to detect myocardial scar. A Look-Locker technique (temporal resolution, 40 ms; slice thickness, 8 mm; repetition time, 3 R-R intervals) for measurements of T1 was used for detecting of LV diffuse fibrosis. Furthermore, cine MRI and 3 D coronary artery imaging were performed to assess ventricular function and coronary anatomy. Results

0357: 3D transthoracic echocardiography to assess ventricular septal defect anatomy and severity

The pathophysiology of Ventricular Septal Defect (VSD) is determined by the size of the defect and the state of the pulmonary vascular resistance. We assessed the morphology of VSD using 3D transthoracic echocardiography (3D-TTE) and the ability to estimate the pathophysiology. We prospectively enrolled 48 children with isolated unique muscular (77%) and membranous VSD (23%). Severity of the VSD was rated according to their pathophysiology. (Type 1: minor left-to-right shunt; 2a: significant left-to-right shunt (left ventricular end diastolic diameter (LVEDD) Zscore >2); 2b: VSD associated with pulmonary hypertension). VSD measurements were obtained after a multi-planar reconstruction of a TTE 3D full volume (X5-1 or X7-2 matrix probes, ie33, Philips). Diagnosis properties of the ratio of 3D-VSD area to aortic annulus area (3DA/AAA), 3D-VSD area to body surface area (3DA/BSA) and 2Dmax diameter to BSA (2DD/BSA) were compared. Median age was 8.5 month-old (min 1 max 123). LVEDD Zscore was >2 in 19 children (40%), of whom 12 (25%) had pulmonary hypertension. 3D-VSD systolic area, 3D and 2D maximal diameters were correlated with LVEDD. (r=0.71, r=0.52, r=0.55, p<0.05). Systolo-diastolic variation of 3D VSD area was higher in muscular than in membranous VSD (Median 54%vs27%, p=0.0001). VSD were asymmetric with a mean ratio of maximal to minimal 3D diameters of 2.1±1.3 in membranous VSD and 3.2±1.5 in muscular VSD (p=0.01). VSD severity was correlated with 3DA/AAA and 3DA/ BSA ratio (r=0.63, r=0.60, p<0.05), but not with the 2DD/BSA ratio. Ability to diagnose type 2b VSD was higher with the 3DA/AAA or 3DA/BSA ratio than the 2D/BSA ratio (ROC area 0.97 and 0.96 vs 0.85). A 3DA/AAA ratio>0.39 has a sensitivity of 92% and a specificity of 97% to diagnose a 2b-VSD. 3D-TTE allows a morphological and a quantitative assessment of muscular and membranous VSD. The 3DA/AAA ratio is an accurate diagnostic tool to assess the pathophysiology of the VSD (figure next page). Abstract 0357 – Figure: 3D systolic and diastolic view of a VSD

Abstract 15015: Multimodal in vivo Computed Tomography and Optical Imaging for Simultaneous Functional, Metabolic and Molecular Myocardial Analysis

Introduction and Hypothesis: The prevalence of myocardial infarction increases with the average age of the population and is currently the leading cause of death worldwide. In order to define anatomical changes and biomarkers related to cardiac infarction, we tested the use of combined computed tomography (CT) and near infrared fluorescent (NIRF) probes to facilitate non-invasive imaging of processes concerned with tissue degeneration/regeneration. This development of new non-invasive diagnostic methods will lead to better treatment options in the future. Methods: Mice were subjected to left anterior descending artery (LAD) ligation inducing an acute myocardial infarction and subsequently imaged in vivo using fast and low dose microCT scanning (QuantumFX, Perkin Elmer) and near infrared (NIRF) probes to monitor MMP activity (MMPsense680). Immediate contrast enhanced CT imaging using eXIA160 during its blood-pool phase allowed registration of changes in ventricular anatomy and function of important global parameters, like end-diastolic volume (EDV), end-systolic volume (ESV). These were used to calculate stroke volume (SV), and left ventricular ejection fraction (LVEF). Delayed eXIA160 contrast uptake during its myocardial phase, subsequently allowed analysis of the infarct size and infarct healing. In addition, in vivo molecular MMPsense localization was combined with micro-CT imaging for accurate 3D co-registration. Results: Changes in ventricular anatomy and myocardial viability were assessed 3 hours and 2 months post LAD occlusion in the same animal, demonstrating the feasibility of monitoring myocard viability over time. The decreased uptake of eXIA160 in the myocardium was subsequently quantitated. A concomitant increase in MMP activity, as determined by fluorescence mediated tomography using MMPsense680, could be localized to the infarcted site. Conclusions: Non-invasive imaging, using NIRF probes, enables longitudinal imaging of processes concerned with myocard infarction. Consequently, disease progression can be monitored over time and the effect of (new) pharmacotherapy can be studied.