3D Heart Model Research Articles

His bundle pacing in a patient with complete atrioventricular block and congenitally corrected transposition of the great arteries: potential of the use of extended reality and cardiac electrical activity projected into 3D heart model.

His bundle pacing in a patient with complete atrioventricular block and congenitally corrected transposition of the great arteries: potential of the use of extended reality and cardiac electrical activity projected into 3D heart model.

Three-Dimensional Heart Modeling of Hypertrophic Obstructive Cardiomyopathy for In Situ Patient-Specific Simulation to Optimize Septal Myectomy.

Hypertrophic obstructive cardiomyopathy (HOCM) develops in at least 1 out of 715 young adults. Patients who are refractory to medical therapy qualify for septal myectomy. Due to anatomy, serious complications such as ventricular septal defect and heart block may occur. Establishing cardiovascular magnetic resonance (CMR)-based 3-dimensional (3D) models as part of preoperative planning and training has the potential to decrease procedure-related complications and improve results. CMR images were used to segment cardiac structures. Left ventricular wall thickness was calculated and projected on top of the in silico model. A 3D model was printed with a red layer indicating a wall thickness exceeding 15 mm and used for preoperative resection planning and patient counseling. To provide preoperative patient-specific in situ simulation, the planned resection volume was replaced with silicone in a second model. For perioperative quality control, resected silicone was compared with resected myocardial tissue. The impact of the models was evaluated descriptively through consultation of both the cardiothoracic surgeon and patients and through patient outcomes. Three-dimensional in silico and 3D-printed heart models of 5 patients were established preoperatively. Since the introduction of the models in October 2020, the surgeon feels better prepared, more confident, and less difficulty with making decisions. In addition, patients feel better informed preoperatively. Using 3D heart models optimized preoperative planning and training, intraoperative quality control, and patient consultation. Reduction of procedure-related complications and clinical outcome should be studied in larger cohorts.

Concordance of left ventricular volumes and function measurements between two human readers, a fully automated AI algorithm, and the 3D heart model.

Echocardiography is essential in cardiovascular medicine for screening, diagnosis, and monitoring. Artificial intelligence (AI) has the potential to improve echocardiography by reducing variability and analysis time. While 3D echocardiography is becoming more accurate, 2D imaging still dominates clinical care. We aimed to evaluate agreement in measures of left ventricular (LV) volumes and function between human readers, a fully automated AI 2D algorithm, and the 3D Heart Model. A retrospective analysis was conducted on 109 patients who underwent 2D and 3D transthoracic echocardiography. LV end-diastolic and end-systolic volumes (LVEDV, LVESV) and ejection fraction (LVEF) were measured by two operators, a commercially available AI algorithm (US2ai), and the 3D Heart Model. Global longitudinal strain (GLS) was measured by the integrated semi-automated software and the AI algorithm. Outcomes included measures of agreement [bias, limit of agreement and Pearson's correlation (R)]. For LV volume measurements, the AI algorithm was strongly correlated with the average of the human operators (r = 0.89 for LVEDV and r = 0.92 for LVESV), which was higher than between the operators (r = 0.74 and r = 0.84, respectively, p < 0.01). The same trend was seen for measures of reliability with respect to LVEDV, but not LVESV. AI demonstrated comparable performance to human operators in measuring LVEF, while the 3D Heart Model had a weaker correlation and reliability compared with human operators and AI measurements. The correlation between human operators and AI for GLS was only moderate. This study demonstrates AI-based echocardiography as a promising tool for accurately assessing LV volumes and LVEF in clinical practice. AI-based measures demonstrated a significantly lower inter-operator variability, thereby improving the consistency and reliability of these assessments. Moreover, AI may prove particularly effective for conducting retrospective bulk analyses, offering a valuable tool for comprehensive evaluations of past data.

Advancements in Finite Element Modeling for Cardiac Device Leads and 3D Heart Models.

The human heart's remarkable vitality necessitates a deep understanding of its mechanics, particularly concerning cardiac device leads. This paper presents advancements in finite element modeling for cardiac leads and 3D heart models, leveraging computational simulations to assess lead behavior over time. Through detailed modeling and meshing techniques, we accurately captured the complex interactions between leads and heart tissue. Material properties were assigned based on ASTM (American Society for Testing and Materials) standards and in vivo exposure data, ensuring realistic simulations. Our results demonstrate close agreement between experimental and simulated data for silicone insulation in pacemaker leads, with a mean force tolerance of 19.6 N ± 3.6 N, an ultimate tensile strength (UTS) of 6.3 MPa ± 1.15 MPa, and a percentage elongation of 125% ± 18.8%, highlighting the effectiveness of simulation in predicting lead performance. Similarly, for polyurethane insulation in ICD leads, we found a mean force of 65.87 N ± 7.1 N, a UTS of 10.7 MPa ± 1.15 MPa, and a percentage elongation of 259.3% ± 21.4%. Additionally, for polyurethane insulation in CRT leads, we observed a mean force of 53.3 N ± 2.06 N, a UTS of 22.11 MPa ± 0.85 MPa, and a percentage elongation of 251.6% ± 13.2%. Correlation analysis revealed strong relationships between mechanical properties, further validating the simulation models. Classification models constructed using both experimental and simulated data exhibited high discriminative ability, underscoring the reliability of simulation in analyzing lead behavior. These findings contribute to the ongoing efforts to improve cardiac device lead design and optimize patient outcomes.

A patient-based realistic simulation platform to train future electrophysiologists to complex ablation procedures

Abstract Title An immersive catheter ablation platform based on patients’ 3D heart model for the simulation and training of future electrophysiologists. Background Arrhythmias are on the rise worldwide due to the ageing of the population. Projections urge to train the next generation of electrophysiologists (EPs) to perform catheter (CATH) ablation (CA) of arrhythmias. Training of future EPs relies mostly on a companionship, where teaching of CATH steerability is made on patients (pts) referred for procedures. While several other domains have established the utility of simulators to speed up learning process, increase safety and establish procedure road maps, dedicated simulators for EPs based on pts’ real anatomy do not exist yet. Purpose To speed up the handling of steerable CATH on MRI-based 3D heart models to optimize ablation road maps in pts referred for complex arrhythmias. Methods ARTS is an Artificial Intelligence and Augmented Reality-based platform comprising two key components: HeARTS and ARTSim. HeARTS is designed to automatically generate 3D heart models from pts’ MRI scans. ARTSim is a CA simulator that utilizes the 3D heart models of the pts for the planning and simulation of CA procedures. This simulator incorporates innovative techniques for digitizing and tracking the movements of a physical catheter in real time, and enabling its navigation within a completely virtual heart. With this technology, the CATH can be precisely steered to various heart locations, including the right and left (LA) atrium, the coronary sinus, and the right and left (LV) ventricles. Results Panel A of the figure shows the mannequin used for the simulator, where a real ablation CATH is introduced within the pt’s heart through a venous introducer. Panel B shows right anterior oblique (RAO) and modified RAO views of a pt suffering from a typical right atrial flutter. Note the presence of yellow tags positioned along the cavotricuspid isthmus (CTI) that the trainee must reach for a programmable duration using the shaft and the handle of the CATH shown in panel A. Panel C shows the virtual ablation CATH in green positioned on the target dots of the CTI. The pink color indicates that the trainee reached the desired target, which became red when the CATH remained stable at the same location for a duration of 5 sec (i.e. stability) with a force &amp;gt;5g (i.e. efficacy) and &amp;lt;20g (i.e. safety). Conclusions Herein, we present ARTS, a realistic CA simulation platform for the training of future EPs, that offers all the typical characteristics of 3D navigation including steerability, stability measurements and the force applied. Importantly, ARTS is based on the true anatomy of the pts, hence might be used to establish and discuss roadmaps to optimize procedures efficacy and safety. Version 2.0, foreseen early 2024, will include 3D late gadolinium enhancement and transseptal puncture for virtual LA and LV procedures, and later on activation times and myocardial voltage.Figure

The effect of 3D modeling on family quality of life, surgical success, and patient outcomes in congenital heart diseases: objectives and design of a randomized controlled trial.

Understanding the severity of the disease from the parents' perspective can lead to better patient outcomes, improving both the child's health-related quality of life and the family's quality of life. The implementation of 3-dimensional (3D) modeling technology in care is critical from a translational science perspective. The purpose of this study is to determine the effect of 3D modeling on family quality of life, surgical success, and patient outcomes in congenital heart diseases. Additionally, we aim to identify challenges and potential solutions related to this innovative technology. The study is a two-group pretest-posttest randomized controlled trial protocol. The sample size is 15 in the experimental group and 15 in the control group. The experimental group's heart models will be made from their own computed tomography (CT) images and printed using a 3D printer. The experimental group will receive surgical simulation and preoperative parent education with their 3D heart model. The control group will receive the same parent education using the standard anatomical model. Both groups will complete the Sociodemographic Information Form, the Surgical Simulation Evaluation Form - Part I-II, and the Pediatric Quality of Life Inventory (PedsQL) Family Impacts Module. The primary outcome of the research is the average PedsQL Family Impacts Module score. Secondary outcome measurement includes surgical success and patient outcomes. Separate analyses will be conducted for each outcome and compared between the intervention and control groups. Anomalies that can be clearly understood by parents according to the actual size and dimensions of the child's heart will affect the preoperative preparation of the surgical procedure and the recovery rate in the postoperative period.

Modeling acute myocardial infarction and cardiac fibrosis using human induced pluripotent stem cell-derived multi-cellular heart organoids.

Heart disease involves irreversible myocardial injury that leads to high morbidity and mortality rates. Numerous cell-based cardiac in vitro models have been proposed as complementary approaches to non-clinical animal research. However, most of these approaches struggle to accurately replicate adult human heart conditions, such as myocardial infarction and ventricular remodeling pathology. The intricate interplay between various cell types within the adult heart, including cardiomyocytes, fibroblasts, and endothelial cells, contributes to the complexity of most heart diseases. Consequently, the mechanisms behind heart disease induction cannot be attributed to a single-cell type. Thus, the use of multi-cellular models becomes essential for creating clinically relevant in vitro cell models. This study focuses on generating self-organizing heart organoids (HOs) using human-induced pluripotent stem cells (hiPSCs). These organoids consist of cardiomyocytes, fibroblasts, and endothelial cells, mimicking the cellular composition of the human heart. The multi-cellular composition of HOs was confirmed through various techniques, including immunohistochemistry, flow cytometry, q-PCR, and single-cell RNA sequencing. Subsequently, HOs were subjected to hypoxia-induced ischemia and ischemia-reperfusion (IR) injuries within controlled culture conditions. The resulting phenotypes resembled those of acute myocardial infarction (AMI), characterized by cardiac cell death, biomarker secretion, functional deficits, alterations in calcium ion handling, and changes in beating properties. Additionally, the HOs subjected to IR efficiently exhibited cardiac fibrosis, displaying collagen deposition, disrupted calcium ion handling, and electrophysiological anomalies that emulate heart disease. These findings hold significant implications for the advancement of in vivo-like 3D heart and disease modeling. These disease models present a promising alternative to animal experimentation for studying cardiac diseases, and they also serve as a platform for drug screening to identify potential therapeutic targets.

A Novel Approach to Cardiac Magnetic Resonance Scar Characterization in Patients Affected by Cardiac Amyloidosis: A Pilot Study.

Background and Objectives: Cardiac magnetic resonance (CMR) imaging has become an essential instrument in the study of cardiomyopathies; it has recently been integrated into the diagnostic workflow for cardiac amyloidosis (CA) with remarkable results. An additional emerging role is the stratification of the arrhythmogenic risk by scar analysis and the possibility of merging these data with electro-anatomical maps. This is made possible by using a software (ADAS 3D, Galgo Medical, Barcelona, Spain) able to provide 3D heart models by detecting fibrosis along the whole thickness of the myocardial walls. Little is known regarding the applications of this software in the wide spectrum of cardiomyopathies and the potential benefits have yet to be discovered. In this study, we tried to apply the ADAS 3D in the context of CA. Materials and Methods: This study was a retrospectively analysis of consecutive CMR imaging of patients affected by CA that were treated in our center (Marche University Hospital). Wherever possible, the data were processed with the ADAS 3D software and analyzed for a correlation between the morphometric parameters and follow-up events. The outcome was a composite of all-cause mortality, unplanned cardiovascular hospitalizations, sustained ventricular arrhythmias (VAs), permanent reduction in left ventricular ejection fraction, and pacemaker implantation. The secondary outcomes were the need for a pacemaker implantation and sustained VAs. Results: A total of 14 patients were deemed eligible for the software analysis: 8 patients with wild type transthyretin CA, 5 with light chain CA, and 1 with transthyretin hereditary CA. The vast majority of imaging features was not related to the composite outcome, but atrial wall thickening displayed a significant association with both the primary (p = 0.003) and the secondary outcome of pacemaker implantation (p = 0.003). The software was able to differentiate between core zones and border zones of scars, with the latter being the most extensively represented in all patients. Interestingly, in a huge percentage of CMR images, the software identified the highest degree of core zone fibrosis among the epicardial layers and, in those patients, we found a higher incidence of the primary outcome, without reaching statistical significance (p = 0.18). Channels were found in the scar zones in a substantial percentage of patients without a clear correlation with follow-up events. Conclusions: CMR imaging plays a pivotal role in cardiovascular diagnostics. Our analysis shows the feasibility and applicability of such instrument for all types of CA. We could not only differentiate between different layers of scars, but we were also able to identify the presence of fibrosis channels among the different scar zones. None of the data derived from the ADAS 3D software seemed to be related to cardiac events in the follow-up, but this might be imputable to the restricted number of patients enrolled in the study.

The new era of cardiovascular research: revolutionizing cardiovascular research with 3D models in a dish.

Cardiovascular research has heavily relied on studies using patient samples and animal models. However, patient studies often miss the data from the crucial early stage of cardiovascular diseases, as obtaining primary tissues at this stage is impracticable. Transgenic animal models can offer some insights into disease mechanisms, although they usually do not fully recapitulate the phenotype of cardiovascular diseases and their progression. In recent years, a promising breakthrough has emerged in the form of invitro three-dimensional (3D) cardiovascular models utilizing human pluripotent stem cells. These innovative models recreate the intricate 3D structure of the human heart and vessels within a controlled environment. This advancement is pivotal as it addresses the existing gaps in cardiovascular research, allowing scientists to study different stages of cardiovascular diseases and specific drug responses using human-origin models. In this review, we first outline various approaches employed to generate these models. We then comprehensively discuss their applications in studying cardiovascular diseases by providing insights into molecular and cellular changes associated with cardiovascular conditions. Moreover, we highlight the potential of these 3D models serving as a platform for drug testing to assess drug efficacy and safety. Despite their immense potential, challenges persist, particularly in maintaining the complex structure of 3D heart and vessel models and ensuring their function is comparable to real organs. However, overcoming these challenges could revolutionize cardiovascular research. It has the potential to offer comprehensive mechanistic insights into human-specific disease processes, ultimately expediting the development of personalized therapies.

Preoperative surgical planning for biventricular repair of double outlet right ventricle by using a 3D heart model.

Preoperative surgical planning for biventricular repair of double outlet right ventricle by using a 3D heart model.

Development of a three-dimensional computer model of the equine heart using a polyurethane casting technique and in vivo contrast-enhanced computed tomography

Introduction/objectivesInsight into the three-dimensional (3D) anatomy of the equine heart is essential in veterinary education and to develop minimally invasive intracardiac procedures. The aim was to create a 3D computer model simulating the in vivo anatomy of the adult equine heart. AnimalsTen horses and five ponies. Materials and methodsTen horses, euthanized for non-cardiovascular reasons, were used for in situ cardiac casting with polyurethane foam and subsequent computed tomography (CT) of the excised heart. In five anaesthetized ponies, a contrast-enhanced electrocardiogram-gated CT protocol was optimized to image the entire heart. Dedicated image processing software was used to create 3D models of all CT scans derived from both methods. Resulting models were compared regarding relative proportions, detail and ease of segmentation. ResultsThe casting protocol produced high detail, but compliant structures such as the pulmonary trunk were disproportionally expanded by the foam. Optimization of the contrast-enhanced CT protocol, especially adding a delayed phase for visualization of the cardiac veins, resulted in sufficiently detailed CT images to create an anatomically correct 3D model of the pony heart. Rescaling was needed to obtain a horse-sized model. ConclusionsThree-dimensional computer models based on contrast-enhanced CT images appeared superior to those based on casted hearts to represent the in vivo situation and are preferred to obtain an anatomically correct heart model useful for education, client communication and research purposes. Scaling was, however, necessary to obtain an approximation of an adult horse heart as cardiac CT imaging is restricted by thoracic size.

CineECG for visualization of changes in ventricular electrical activity during ischemia

Abstract Background CineECG is a newly developed method which provides an anatomical visualization of ventricular de- and repolarization in a non-invasive manner. It combines the electrical information from the 12-lead electrocardiogram (ECG) with a 3D heart model. The location and direction of the average ventricular de- and repolarization over time is projected on the model. Until now, it has not been used for visualization of ventricular electrical activity during myocardial ischemia. Purpose We aimed to visualize changes in ventricular de- and repolarization during acute ischemia with CineECG and relate these to changes in the ECG. Methods CineECG was used to provide the location and direction of the average ventricular de- and repolarization over time, using a standardized 3D heart/torso model. Continuous ECG’s during percutaneous transluminal coronary angioplasty with prolonged balloon inflation from the STAFF III database were used as study sample. ECG’s at baseline and at every 10 seconds during the first 150 seconds of balloon inflation were analyzed with CineECG. For the terminal QRS-complex, ST-segment and terminal T-wave, the direction of the CineECG was determined. The changes in CineECG direction relative to the direction at baseline were quantified by calculating the Δangle between the CineECG direction at baseline and the direction after every 10 seconds of inflation. Additionally, the root mean square amplitude (rmsA) of the ST-segment of all ECG leads was computed for every ECG. Results 94 patients from the STAFF III database were included, 10 patients were excluded due to too much signal noise of the ECG. Within 10 seconds after start inflation, the median Δangle for the terminal QRS-complex, ST-segment and terminal T-wave were 21.8° [11.4 – 34.2] , 20.6° [8.0 – 43.9] and 23.5° [11.8 – 48.0], respectively. The median Δangle for the terminal QRS-complex reached its maximum after 130 seconds (41.0° [23.0 – 70.8]). The median Δangle of the ST-segment gradually increased to 26.1° [13.1 – 56.0] after 140 seconds of inflation. The Δangle of the terminal T-wave was greatest 30 seconds after start inflation (26.3° [12.6 – 49.2]), and changed only slightly during inflation. The rmsA of the ST-segment was 0.04 mV [0.03 – 0.08] during the first 10 seconds of inflation, and gradually increased until 0.08 mV [0.05 – 0.15] mV at 150 seconds. Conclusions CineECG proves to be very sensitive in detection of early changes in the ECG during prolonged balloon inflation, even before great changes occur in ST-amplitude. Therefore, CineECG might support the early detection of acute ischemia, even before clear ECG changes are visible.

Three-dimensional-printed heart model can determine univentricular repair strategy in borderline double-outlet right ventricle

BackgroundAs double-outlet right ventricle has a wide pathophysiology spectrum, its comprehensive treatment strategy is determined based on relevant factors, such as the location and size of the ventricular septal defect, ventricular volume, and relationship of the great arteries. However, for borderline double-outlet right ventricle cases, it is occasionally difficult to decide the treatment strategy preoperatively. Recently, advances in 3D printing technology based on computed tomography have enabled the creation of 3D heart models of congenital heart disease that can precisely reproduce the anatomical structure of each patient even for complex anomalies. Herein, we describe a young patient in whom univentricular repair could be decided after confirming the 3D heart model and intracardiac structure under direct vision.Case presentationWe describe a 3-year-old girl who was diagnosed with double-outlet right ventricle and severe pulmonary valve stenosis at birth and who underwent a left modified Blalock–Taussig shunt at 2 years of age. Preoperative examination revealed a borderline condition for biventricular repair characterized by a small left ventricle volume and side-by-side relationship of the great artery. After a preoperative discussion using a 3D heart model, we concurred that an intraoperative assessment would be made as to whether biventricular repair was possible or not. After confirming the intracardiac structure under direct vision, we assessed that intraventricular rerouting was not possible owing to the high risk of subvalvular aortic stenosis as there was no tissue that could be incised between the right ventricular free wall and the primary interventricular foramen, as indicated in the 3D heart model. Thus, atrial septostomy and Glenn anastomosis were performed.ConclusionsWe report a 3-year-old girl with a borderline double-outlet right ventricle in whom a univentricular repair strategy could be decided after confirming the 3D heart model and intracardiac structure under direct vision. A 3D-printed heart model can be useful in patients whose repair strategy is difficult to judge for the borderline double-outlet right ventricle.

"From Vision to Reality: Virtual Reality's Impact on Baffle Planning in Congenital Heart Disease".

This study aims to evaluate the feasibility and utility of virtual reality (VR) for baffle planning in congenital heart disease (CHD), specifically by creating patient-specific 3D heart models and assessing a user-friendly VR interface. Patient-specific 3D heart models were created using high-resolution imaging data and a VR interface was developed for baffle planning. The process of model creation and the VR interface were assessed for their feasibility, usability, and clinical relevance. Collaborative and interactive planning within the VR space were also explored. The study findings demonstrate the feasibility and usefulness of VR in baffle planning for CHD. Patient-specific 3D heart models generated from imaging data provided valuable insights into complex spatial relationships. The developed VR interface allowed clinicians to interact with the models, simulate different baffle configurations, and assess their impact on blood flow. The VR space's collaborative and interactive planning enhanced the baffle planning process. This study highlights the potential of VR as a valuable tool in baffle planning for CHD. The findings demonstrate the feasibility of using patient-specific 3D heart models and a user-friendly VR interface to enhance surgical planning and patient outcomes. Further research and development in this field are warranted to harness the full benefits of VR technology in CHD surgical management.

Examination of a Human Heart Fabricating Its 3D-Printed Cardiovascular Model and Employing Computational Technologies

In this paper, an innovative approach concerning the investigation of the human heart is introduced, employing state-of-the-art technologies. In particular, sophisticated algorithms were developed to automatically reconstruct a 3D model of a human heart based on DICOM data and to segment the main parts that constitute it. Regarding the reconstructed 3D model, a diagnosis of the examined patient can be derived, whereas in the present study, a clinical case involving the coarctation of the aorta was inspected. Moreover, numerical approaches that are able to simulate flows on complex shapes were considered. Thereupon, the outcomes of the computation analysis coupled with the segmented patient-specific 3D model were inserted in a virtual reality environment, where the clinicians can visualize the blood flow at the vessel walls and train on real-life medical scenarios, enhancing their procedural understanding prior to the actual operation. The physical model was 3D-printed via the MultiJet 3D printing process utilizing materials possessing an adequate mechanical response replicating the mechanical properties and the geometrical characteristics of the human heart. The presented tools aim at the creation of an innovative digital environment, where gaining surgical experience and developing pre-operative strategies could be achieved without the risk and anxiety of actual surgery.

Electrocardiographic temporo-spatial assessment of depolarization and repolarization changes after epicardial arrhythmogenic substrate ablation in Brugada syndrome.

In Brugada syndrome (BrS), with spontaneous or ajmaline-induced coved ST elevation, epicardial electro-anatomic potential duration maps (epi-PDMs) were detected on a right ventricle (RV) outflow tract (RVOT), an arrhythmogenic substrate area (AS area), abolished by epicardial-radiofrequency ablation (EPI-AS-RFA). Novel CineECG, projecting 12-lead electrocardiogram (ECG) waveforms on a 3D heart model, previously localized depolarization forces in RV/RVOT in BrS patients. We evaluate 12-lead ECG and CineECG depolarization/repolarization changes in spontaneous type-1 BrS patients before/after EPI-AS-RFA, compared with normal controls. In 30 high-risk BrS patients (93% males, age 37 + 9 years), 12-lead ECGs and epi-PDMs were obtained at baseline, early after EPI-AS-RFA, and late follow-up (FU) (2.7-16.1 months). CineECG estimates temporo-spatial localization during depolarization (Early-QRS and Terminal-QRS) and repolarization (ST-Tpeak, Tpeak-Tend). Differences within BrS patients (baseline vs. early after EPI-AS-RFA vs. late FU) were analysed by Wilcoxon signed-rank test, while differences between BrS patients and 60 age-sex-matched normal controls were analysed by the Mann-Whitney test. In BrS patients, baseline QRS and QTc durations were longer and normalized after EPI-AS-ATC (151 ± 15 vs. 102 ± 13 ms, P < 0.001; 454 ± 40 vs. 421 ± 27 ms, P < 0.000). Baseline QRS amplitude was lower and increased at late FU (0.63 ± 0.26 vs. 0.84 ± 13 ms, P < 0.000), while Terminal-QRS amplitude decreased (0.24 ± 0.07 vs. 0.08 ± 0.03 ms, P < 0.000). At baseline, CineECG depolarization/repolarization wavefront prevalently localized in RV/RVOT (Terminal-QRS, 57%; ST-Tpeak, 100%; and Tpeak-Tend, 61%), congruent with the AS area on epi-PDM. Early after EPI-AS-RFA, RV/RVOT localization during depolarization disappeared, as Terminal-QRS prevalently localized in the left ventricle (LV, 76%), while repolarization still localized on RV/RVOT [ST-Tpeak (44%) and Tpeak-Tend (98%)]. At late FU, depolarization/repolarization forces prevalently localized in the LV (Terminal-QRS, 94%; ST-Tpeak, 63%; Tpeak-Tend, 86%), like normal controls. CineECG and 12-lead ECG showed a complex temporo-spatial perturbation of both depolarization and repolarization in BrS patients, prevalently localized in RV/RVOT, progressively normalizing after epicardial ablation.

Fast-Track Virtual Reality to Facilitate 3D Reconstruction in Congenital Heart Disease.

A limitation of the clinical use of 3D reconstruction and virtual reality (VR) systems is the relatively high cost and experience required to use hardware and software to effectively explore medical images. We have tried to simplify the process and validate a new tool developed for this purpose with a novel software. Five patients with right partial anomalous pulmonary venous return with adequate preoperative imaging acquired by magnetic resonance were enrolled. Five volunteers with no previous experience in the field of 3D reconstruction were instructed to use the software after a short video tutorial. Users were then asked to create a 3D model of each patient's heart with DIVA and their results were compared quantitatively and qualitatively with a benchmark reconstruction performed by an experienced user. All our participants recreated 3D models in a relatively short time, maintaining a good overall quality (average quality score ≥ 3 on a scale of 1-5). The overall trend of all the parameters analysed showed a statistical improvement between Case 1 and Case 5, as users become more and more experienced. DIVA is a very simple software that allows accurate 3D reconstruction in a relatively short time ("fast-track" VR). In this study, we demonstrated the potential use of DIVA by inexperienced users, with a significant improvement in quality and time after a few cases were performed. Further studies are needed to confirm the potential application of this technology on a larger scale.

The last shall be the first: the role of combined QLV- and CMR-determined electromechanical concordance in predicting optimal left ventricular stimulation site in cardiac resynchronisation therapy

Abstract Funding Acknowledgements Type of funding sources: None. Background/introduction Optimisation of cardiac resynchronisation therapy (CRT) response still represents a significant challenge to cardiac electrophysiology. In this regard, perhaps the area of greatest uncertainty revolves around optimal left ventricular lead (LVL) position and in particular whether this should be directed at areas of latest electrical or mechanical activation given the equivocal evidence on their precise relationship in heart failure (HF) patients. Furthermore, while echocardiography has demonstrated that LVL aimed at regions of greatest mechanical delay maximises CRT response, cardiac magnetic resonance (CMR) with its greater spatial resolution and tissue definition is yet to demonstrate a role in doing so. Purpose To retrospectively evaluate concordance between latest electrical and CMR-determined mechanical activation in a CRT population and its relationship with reverse remodeling. Methods This is a retrospective single center analysis of 104 CRT patients. All patients had CMR and echocardiography performed before implantation. During implantation, coronary sinus angiogram was performed and electrical delay (QLV time with RV-LV time greater than 80 ms) was mapped on all veins suitable for lead implantation and LVL was positioned in the region of latest electrical activation programming LVL cathode accordingly. LVL cathode position was thus assumed to represent the region of latest electrical delay. A post-hoc analysis was then conducted by means of CART-Tech® software providing radial strain and scar maps on a 36-segment anatomical model. Patients were then stratified based on concordance between LVL cathode position (using 3D heart models superimposed on 2D angiography images) and most mechanically delayed segments (either the three most delayed segments or adjacent ones) or non concordance (one or more segments between LVL cathode and three most mechanically delayed segments). Data from patient follow-up was collected with echocardiography at least 3 months after implant date. CRT response was expressed as reduction in end-systolic volume (ESV) greater than 15%. Results A preliminary analysis of the first 30 patients of our cohort was conducted. Electromechanical concordance and non-concordance were present in 24 and 6 patients, respectively. Baseline patient characteristics including demographics, comorbidities, HF aetiology, ECG and echocardiography features were comparable between groups except for scar burden, which was higher in the non-concordance group. Response to CRT was 80% in the concordant vs. 20% in the non-concordant group. Conclusions While a confounding effect of scar burden cannot be excluded, these preliminary data suggest that electromechanical concordance in LVL cathode placement may represent a predictor of optimal CRT response. The full scope of this study will be fully appreciated in the coming month on completion of analysis of the entire patient cohort.

LivHeart: A Multi Organ‐on‐Chip Platform to Study Off‐Target Cardiotoxicity of Drugs Upon Liver Metabolism

AbstractThe drug discovery and development process is still long, costly, and highly risky. The principal attrition factor is undetected toxicity, with hepatic and cardiac toxicities playing a critical role and being the main responsible of safety‐related drug withdrawals from the market. Multi Organs‐on‐Chip (MOoC) represent a disruptive solution to study drug‐related effects on several organs simultaneously and to efficiently predict drug toxicity in preclinical trials. Specifically focusing on drug safety, different technological features are applied here to develop versatile MOoC platforms encompassing two culture chambers for generating and controlling the type of communication between a metabolically competent liver model and a functional 3D heart model. The administration of the drug Terfenadine, a cardiotoxic compound liver‐metabolized into the noncardiotoxic Fexofenadine, proves that liver metabolism and a fine control over drug diffusion are fundamental to elicit a physio‐pathological cardiac response. From these results, an optimized LivHeart platform is developed to house a liver model and a cardiac construct that can be mechanically trained to achieve a beating microtissue, whose electrophysiology can be directly recorded in vitro. The platform is proved able to predict off‐target cardiotoxicity of Terfenadine after liver metabolism both in terms of cell viability and functionality.

Utility of three-dimensional virtual and printed models for veterinary student education in congenital heart disease

Introduction: Congenital heart disease (CHD) is a common heart defect that can be present in small and large animals at birth. Student understanding of normal and abnormal cardiac anatomy is imperative for proper diagnosis and management of CHD. Objectives were to create and use three-dimensional (3D) heart models during a workshop to understand veterinary student perception of 3D models for CHD education. We hypothesized that 3D models would enhance student understanding of CHD, and students would prefer 3D models during cardiac education. Materials and Methods: Computed tomography angiography datasets from canine patent ductus arteriosus were used to create 3D models. Segmentation and computer-aided design were performed. Virtual overlays of 3D models were displayed onto two-dimensional (2D) thoracic radiographs. Stereolithography files were fabricated by a 3D printer. Students participated in a CHD workshop consisting of 2D and 3D teaching stations. Self-assessment surveys before and after the workshop were completed. Results: Twenty-two veterinary students attended the workshop. The 3D-printed models were found to be the most helpful teaching modality based on students’ perception. The 3D-printed model (P < 0.0001) and the 3D digital model (P < 0.0001) were perceived to be significantly more helpful than the 2D radiograph station. All students strongly agreed (15/22) or agreed (7/22) that virtual models overlayed onto 2D radiographs enhanced their spatial recognition of anatomic structures. All students strongly agreed (17/22) and agreed (5/22) that the CHD workshop was a valuable learning opportunity. Conclusion: Creation of virtual and fabricated 3D heart models is feasible. Three-dimensional models may be helpful when understanding spatial recognition of cardiovascular anatomy on thoracic radiographs. We advocate using 3D heart models during CHD education.