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Transcatheter therapies are a common way to treat cardiovascular diseases. These therapies are complicated by significant anatomical patient-to-patient variations that exist in terms of transcatheter vascular pathways. Adding to the complexity of transcatheter procedures, the training tools used for physician education often overlook vast patient-to-patient variations and utilize idealized models of patient anatomy that may be unrealistic. In this study, anatomically accurate models were created from high-resolution images of real patient vasculatures. Using fourteen human cadavers donated for research, we collected high-resolution images to generate 3D computational renderings of various patient anatomies. These models make up the “Transcatheter Pathways Vasculature Database” that can be used for physician education and training, as well as improving transcatheter delivery system design. We performed multiple studies that emphasize the anatomical differences that exist in patient vasculatures. Using 3D printing and virtual reality, we developed educational materials and benchtop models to train physicians using true patient anatomies. These tools can also provide device designers with data to improve their products based on real patient vessels. The “Transcatheter Pathways Vasculature Database” highlights differences between patient vasculatures. By educating and training physicians with patient anatomies that accurately represent significant patient-to-patient variations, learning is more translatable to what is seen in the clinic.

A pioneering surgeon at the University of Minnesota, Dr C. Walton Lillehei, is still considered the "father of open-heart surgery". Dr Lillehei and his surgical team performed the first open-heart operations utilizing cross-circulation, including the first successful ventricular septal defect closure on a 3-year-old boy. Before his death at age 67, this patient arranged to donate his body to the University of Minnesota's Anatomy Bequest program. We describe this patient's medical history, and present unique images of internal/external cardiac anatomies and implanted devices obtained via direct visualizations, computed tomography, and fluoroscopy post-mortem. Additionally, we present computational models and 3-dimensional printed models.

Background The number of lead extractions is growing because of the greater population and increasing age of individuals with a cardiac implantable electronic device. Lead extraction procedures can be complex undertakings with risk of significant mortality, and vascular tears in the superior vena cava are of greatest concern. Objective The purpose of this study was to study whether a novel algorithm that analyzes pre-extraction computed tomographic (CT) images can determine the likelihood and location of lead–lead interactions and lead–vessel attachment within patients' venous vasculatures. This information can be used to identify potential case challenges in the planning stages. Methods We developed an algorithm to estimate the presence and position of lead–lead interactions and lead–vessel adherences by tracking distance between the leads and distance between the lead and superior vena cava in a sample of 12 patients referred to the United Heart and Vascular Clinic for lead extractions due to infection (n = 5), lead failure (n = 5), and tricuspid regurgitation (n = 2). Results Preliminary results indicate that the developed algorithm successfully identified lead–lead and lead–vascular attachments compared to review of CT images by medical experts. Conclusion With future validation and clinical implementation, this algorithm could aid physician preparedness by minimizing intraprocedural emergencies and may improve patient outcomes.

Transcatheter therapies are a common way to treat cardiovascular diseases. These therapies are complicated by significant anatomical patient-to-patient variations that exist in terms of transcatheter vascular pathways. Adding to the complexity of transcatheter procedures, the training tools used for physician education often overlook vast patient-to-patient variations and utilize idealized models of patient anatomy that may be unrealistic. In this study, anatomically accurate models were created from high-resolution images of real patient vasculatures. Using fourteen human cadavers donated for research, we collected high-resolution images to generate 3D computational renderings of various patient anatomies. These models make up the "Transcatheter Pathways Vasculature Database" that can be used for physician education and training, as well as improving transcatheter delivery system design. We performed multiple studies that emphasize the anatomical differences that exist in patient vasculatures. Using 3D printing and virtual reality, we developed educational materials and benchtop models to train physicians using true patient anatomies. These tools can also provide device designers with data to improve their products based on real patient vessels. The "Transcatheter Pathways Vasculature Database" highlights differences between patient vasculatures. By educating and training physicians with patient anatomies that accurately represent significant patient-to-patient variations, learning is more translatable to what is seen in the clinic.

Graphical Abstract Venous-arterial extracorporeal membrane oxygenation (VA-ECMO) treatment for acute cardiogenic shock in patients who also have acute lung injury predisposes development of a serious complication called “north-south syndrome” (NSS) which causes cerebral hypoxia. NSS is poorly characterized and hemodynamic studies have focused on cerebral perfusion ignoring the heart. We hypothesized in NSS the heart would be more likely to receive hypoxemic blood than the brain due to the proximity of the coronary arteries to the aortic annulus. To test this, we conducted a computational fluid dynamics simulation of blood flow in a human supported by VA-ECMO. Simulations quantified the fraction of blood at each aortic branching vessel originating from residual native cardiac output versus VA-ECMO. As residual cardiac function was increased, simulations demonstrated myocardial hypoxia would develop prior to cerebral hypoxia. These results illustrate the conditions where NSS will develop and the relative cardiac function that will lead to organ-specific hypoxia. Illustration of the impact of north-south syndrome on organ-specific oxygen delivery. Patients on VA-ECMO have two sources of blood flow, one from the VA-ECMO circuit and one from the residual cardiac function. When there is no residual cardiac function, all organs are perfused with oxygenated blood. As myocardial recovery progresses, blood supply from the two sources will begin to mix resulting in non-homogeneous mixing and differential oxygenation based upon the anatomical site of branching vessels. Supplementary Information The online version contains supplementary material available at 10.1007/s12265-021-10110-2.

The emerging field of virtual reality has many promising new applications for the medical sciences. For example, by converting magnetic resonance and tomography-based images into 3D models, users can visually inspect individualized anatomic reconstructions at clinically useful high resolutions. Yet, adequate development of these tools will require a wide breadth of associated expertise to take advantage of current video game technologies while maintaining relevance for clinical use. Our laboratory has begun to implement such system approaches for the exploration of hearts, cadaveric specimens, and medical device-tissue interactions. We have created hundreds of anatomical scenes that were developed using physician feedback from conferences worldwide. We demonstrate several aspects of the potential applicability of virtual reality to serve both clinical science and education, and additionally discuss future prospects.

Implanting Left ventricular assist devices (LVADs) can be life saving therapies that improve life expectancy for the patients that receive it. The target patient population suffer from end-stage heart failure and are therefore susceptible to morbidities arising from a less than ideal surgical implantation. Importantly, the graft that carries the blood from the LVAD pump to the aorta needs to be sized accordingly so as to not cause any compounding complications. The current typical surgical method, is to perform a visual estimation at the time of implantation. This present study proposes a computational tool that utilizes pre-procedural imaging to better calculate the personalized, ideal, LVAD graft length.

There are few medical devices currently utilized that have not had, at the very least, a second iteration. Medical device companies continually strive to improve their product to make it the best on the market. Medical devices are often optimized by defining the size of the device, making it more efficient and/or improving the device to tissue interface. Using the capabilities of the Visible Heart® Laboratories various cardiac devices can be implanted in reanimated swine and human hearts for the assessment of the various aforementioned parameters. After the implantation of these devices and assessment in functional anatomies, specimens were perfusion-fixed and then a micro-CT scanner was utilized to take high-resolution scans of the resultant device and tissue interfaces. These scans are used to generate high-resolution (∼20 microns) 3D models of the numerous implanted devices, measurement analyses, device simulations, and the creation of virtual reality scenes. All can then be used for detailed visual analyses. These abilities to render high-resolution models will allow medical device designers to closely evaluate their designs, in order to optimize their next iterations.

Atrial fibrillation, a common cardiac arrhythmia, can lead to blood clots in the left atrial appendage (LAA) of the heart, increasing the risk of stroke. Understanding the LAA morphology can indicate the likelihood of a blood clot. Therefore, a classification convolutional neural network was implemented to predict the LAA morphology. Using 2D images of 3D models created from MRI scans of fixed human hearts and a pre-trained network, an 8.7% error rate was achieved. The network can be improved with more data or expanded to classify the LAA from the automatically segmented DICOM datasets and measure the LAA ostia.

Medical device designers must develop catheters that avoid harming the vascular pathway during therapy delivery. To better characterize the necessary design features to minimize damage to central and peripheral vessels, the vascular pathway used for femoral delivery of a cardiac device is studied through high resolution, computed tomography images of fresh, human cadavers. Comparisons of the amount and location of vessel calcification are made between specified anatomical sections. Though the potential complications may be less fatal, the descending aorta and iliac regions were found to be most susceptible to embolism in our analysis.

The purpose of this chapter is to highlight the continued importance of studying cadavers for educational and research purposes and to describe how imaging of both fixed and fresh cadavers can enhance these experiences. Specifically, this chapter describes the (1) history of cadaver dissection and preservation, (2) importance of cadaver labs when training medical students about anatomy or physicians on novel medical devices, (3) need for cadaver studies when designing and developing medical devices, and (4) emerging field of high-resolution full-body imaging of cadavers as a means to enhance understanding of device–tissue interactions.

Medical device developers can often be limited in pre-clinical experimental testing of new products because of procedural complexities and safety concerns to the animal or patient. Though animal or human cadavers can be used for these types of studies thereby eliminating the need for safety precautions, the functional capabilities of the tissue can be lost. As a novel way to provide such functional device/tissue assessment, the Visible Heart® (VH®) Laboratory has developed reanimation methodologies1 that allow the four chambers of the heart to contract naturally ex vivo. Swine hearts are routinely reanimated using this methodology with a clear perfusate which allows for direct endoscopic visualization of functional cardiac anatomy and importantly the device/tissue interface. For the past two decades, these capabilities have been useful for testing early device prototypes and developing educational and procedural videos. More specifically, this approach provides the added convenience of manipulating catheters into the ex vivo prep and visually studying their behavior for validation experiments of new medical devices. Further, multimodal imaging comparative assessments using both 4D echocardiography and fluoroscopy have been routinely performed. Yet, as imaging modalities continue to develop and are utilized for device placements or post-procedure evaluations, we hope to expand VH® capabilities.

Newly developed interactive tutorials and applications which teach human anatomy are often set up as pay-to-play websites. Examples of these include the Visible Body app1 and the 3D Organon Anatomy2. Though these applications can be very educational, they may be costly, thus many students and members of the education community will not access these programs because of the upfront charges. These teaching programs are also frequently anatomically limited because they utilize idealized models, like KineMan3, instead of renderings or imaging data sets obtained from humans (clinical or from cadavers). This characteristic may make them useful study tools, but will not best prepare future doctors, nurses, and other health professionals for true, variable patient anatomies they will encounter in their various practices. Further, such students would likely gain more by studying 3D objects of real human anatomies instead of 2D images. We have designed a strategy to bring 3D human anatomies from real cadavers to the scientific and education communities completely open source (free of charge). Our interactive application is geared toward students of all ages (grade school to medical school) or by anyone interested in learning more about human bone anatomy.