This hands-on laboratory, using a swine animal model, will provide participants with the necessary understanding of the safe and effective performance of minimally invasive techniques that can be used for the treatment of various vascular disorders. Participants will gain valuable experience with vascular filter placement and retrieval, along with vascular stenting.
- Animal endovascular interventions operating room
- Ekos system venogram in a pig
- Femoral vein suture in pig model
- Ultrasound imaging of left iliac artery in pig model
Atrial fibrillation (AF) is the most common cardiac arrhythmia seen in clinical practice and a major cause of embolic stroke. Yet, despite more than 100 years of research and speculation, the mechanism of AF is not well understood and therapy is often ineffective. The use of voltage-sensitive probes and high-resolution video imaging in isolated animal hearts has provided support for the hypothesis that AF may be driven by one, or a small number of high-frequency electrical sources called “rotors”. In this laboratory, the following questions will be addressed: (1) What are the mechanisms underlying AF maintenance? (2) What is a rotor and how is it formed? (3) What technologies are available in the basic lab to map the atria and find rotors during AF? (4) What electrical and structural conditions are needed for a rotor to maintain AF indefinitely? And (5) what maneuvers can be used to find rotors when they are hiding from view?
Cardiac mapping setup in a sheep model
Following the FDA’s Critical Path Initiative, Computational Modeling has emerged as a powerful tool to aid in the design and optimization of medical devices. New regulatory infrastructures expect modeling techniques to be used in combination with traditional bench-top methods to accelerate, decrease costs, and increase safety in the production cycle of new medical devices.
In this lab, we will cover the following topics: (1) An overview of physics-based computer simulation; (2) Definition of CAD models and medical image data -based models; (3) Definition of appropriate boundary conditions; (4) Parallel computing principles; and (5) Post-processing and visualization.
Additionally, we will review specific applications in the areas of device performance evaluation in the context of thrombosis potential, and non-invasive diagnostics.
Visualization of blood velocity in a Fontan repair
Small Animal MRI
MRI safety will briefly be discussed (participants will not be allowed or expected to go past the 5 Gauss line). Then, we will focus on imaging and physiological equipment needs, along with image visualization and analysis software. Workflow for efficient and effective preclinical MRI data acquisition will be considered. Basic relaxation mechanisms such as T1, T2, and T2* will be empirically demonstrated in vivo. We will go on to acquire 2D and 3D time-of-flight data (angiography and venography) along with CINE images (vessel wall cyclic strain, cardiac output, blood flow velocity), highlighting the ability of preclinical MRI to noninvasively provide structural and functional information. We will also impart an intuition for the interdependency of MRI sequence parameters with respect to resolution, signal-to-noise, and imaging time. And, lastly, briefly discuss considerations for image interpretation and analysis.
Video of MRI methods for small animal imaging
Histotripsy for Non-invasive Cardiovascular Surgery
Histotripsy is a new non-invasive, image-guided, robotically assisted ultrasound therapy. Using high pressure, microsecond-length ultrasound pulses applied from outside the body and focused to the diseased tissue, histotripsy produces cavitation to fractionation the cells in the target tissue without damaging surrounding tissue. In this lab, the participants will see histotripsy in action for treatment of cardiovascular applications and get hands-on experience of operating an ultrasound image-guided histotripsy system to treat blood clots in an ex vivo vascular phantom.
- Histotripsy transducer laying on a 3D-printed neonatal torso
- Histotripsy transducer on a pig chest delivering pulses to the heart
- Histotripsy experiment aiming to create a lesion in the piglet heart