Biomedical Engineering

Positions Available
Dr. Hoda Hatoum is looking for highly motivated PhD students starting January 2021.

Biofluids Laboratory

The biofluids lab utilizes fluid and solid mechanics principles, clinical expertise and design and manufacturing to find solutions for cardiovascular flow problems. The lab scope involves both basic and translational studies. The lab utilizes a custom-designed and built pulse duplicator system that emulates that of the cardiovascular system. In this flow simulator setup, hemodynamic assessment of adult and congenital heart defects can take place.

Special equipment used in the lab involves a particle image velocimetry system that allows the characterization of the flow field in vessels and organs.

Location: Minerals and Materials 312

Hoda Hatoum

  • Assistant Professor, Biomedical Engineering
  • Affiliated Assistant Professor, Mechanical Engineering-Engineering Mechanics
M&M 402

Heart Valve Design

In the biofluids lab, we design heart valve devices. With the rise of minimally invasive surgeries, the clinical field is moving towards transcatheter approaches. Currently, transcatheter heart valves are made of biological materials that are prone to degeneration leading to compromised valve performance and necessitating another valve replacement ultimately. In the biofluids lab, we collaborate with material science experts to utilize novel biomaterials that are biocompatible, durable and suitable for cardiovascular applications. We also design and optimize stents and leaflet geometries.

Array of various valves.
Image showing the multitude of bioprosthetic transcatheter mitral valve (TMV) devices. There exist more than 20 different designs of TMVs currently. All these valves are made of biological leaflets prone to durability challenges (structural degeneration).

Heart Valve Performance Assessment

In the biofluids lab, we assess the performance and the flow characteristics of different heart valves in idealized chambers or in patient-specific ones. Using our heart simulator and our particle image velocimetry system, multiple commercially available or in-house made heart valves are tested. Valves are tested for (1) Overall performance and energetics (2) turbulence generated (3) sinus hemodynamics (aortic and pulmonic) and (4) ventricular, atrial, pulmonic and aortic flows.

Sequence of CT and 3D model images of the aortic valve.
This image shows the process of segmentation of the Computed Tomography (CT) scan of the patient and the generation of the 3D model of the aortic valve as an example. The models are assessed computationally and experimentally. For the experimental part, the 3D models are 3D printed using compliant material and deployed in the left heart simulator available in the lab. Patient-specific studies help us better translate our benchwork findings by accounting for every patient’s geometry.
Play Biomedical Engineering Biofluids Lab Aortic Valve Models video
Preview image for Biomedical Engineering Biofluids Lab Aortic Valve Models video

In this video, high-speed imaging was taken of 2 commercial transcatheter aortic valves deployed in an idealized model and in a patient-specific model.

Play Biomedical Engineering Biofluids Lab Particle Image Velocimetry video
Preview image for Biomedical Engineering Biofluids Lab Particle Image Velocimetry video

This video shows a particle image velocimetry (PIV) experiment. Using PIV, we shine a laser beam on the region that we are interested in assessing. In our experiments, we utilize a blood analog that is transparent. The fluid is seeded with fluorescent particles that shine upon exposure to the laser beam. Using a specific software, we can calculate the resulting displacement, velocity and any other parameters that we are interested in.

Congenital Heart Defects

In the biofluids lab, we analyze several congenital heart defects and we devise various approaches to help find alternatives for highly-invasive surgeries (Tetralogy of Fallot, pulmonary atresia, double outlet right ventricle, Kawasaki disease, etc.). We collaborate with Nationwide Children’s Hospital to acquire patient data. Using experimental and computational fluid dynamics, we assess different scenarios of design approaches and we develop predictive models to help clinicians with anticipating adverse outcomes.

Array of heart illustrations with different defects.
This image shows a few examples of congenital anomalies.
Apparatus with silicone section.
This image shows the experimental setup with a case of anomalous coronary deployed. The model was 3D printed using silicone and connected to the pulse duplicator for flow assessment.
Apparatus with silicone and plastic sections.
A patient-specific 3D printed model of a Blalock-Taussig shunt patient.