Novel Intracardiac Ultrasound Images Developed on a Cardiac Ultrasound Simulator and Validated in Live Horses

Abstract

Introduction: Ultrasonographic guidance of catheter-based interventions in horses is based primarily on transthoracic echocardiography (TTE). Intracardiac echocardiography (ICE) has the potential to provide detailed imaging of specific cardiac regions. Insight and training in echocardiographic guidance can be acquired using an echocardiography simulator. Hypothesis/Objectives: Use an echocardiography simulator for horses to determine specific ICE views for catheter-based interventions and validate these in live horses. Animals: Six adult healthy experimental horses. Methods: Observational study. An echocardiographic phantom based on a three-dimensional computer model of the equine heart was used. This phantom was positioned in a water tank, allowing simultaneous TTE and ICE catheter introduction. Novel ICE images from within the thoracic inlet and right atrium were determined on the ultrasound simulator, with TTE as back-up modality to determine ICE catheter position in the simulator if necessary. Images were validated in six horses, with adaptations to catheter manipulations where needed. Results: Novel ICE images developed on the ultrasound simulator could be replicated in live horses, with no changes in catheter manipulations. These views allowed visualization of the tributaries of the cranial vena cava, both atria, pulmonary veins, aorta, and pulmonary artery. Conclusions and Clinical Importance: The ultrasound simulator was useful in developing additional ICE images in order to understand echocardiographic anatomy. This simulator creates possibilities for ICE diagnosis of specific cardiac conditions and further development of ICE-guided catheter-based interventions in horses. The ultrasound simulator can be helpful for providing echocardiographic training and reduction of experimental animal use.