Undergraduates Partner with UMass Chan Medical School on Capstone Projects
By Karen Angelo
When someone is waiting for a heart transplant, doctors may implant a small device that supports the beating of the heart while the patient awaits an organ donor. While the device can help save the patient’s life, the electrical signals that it emits can interfere with electrocardiogram (ECG) readings. Doctors cannot distinguish between the signals, making it difficult for them to conduct a cardiac evaluation.
A team of engineering students set out to solve this challenge—as one of five real-world senior capstone projects developed with UMass Chan Medical School doctors and researchers.
The collaboration with the medical school is spearheaded by Prof. Bryan Buchholz, chair of the Department of Biomedical Engineering, and supported by the UMass Center for Clinical and Translational Science.
According to Matthew Palmer ’22, a biomedical engineering major and member of the student team, doctors observed high intensities of these unwanted signals when ventricular assist devices were placed in the chest, rather than in the midsection.
“The ventricular assist device vibrates, which generates muscle movement close to the heart and transmits electrical signals that are observed as noise,” says Palmer.
Under the guidance of Assoc. Prof. Mufeed Mah'd of the Department of Electrical and Computer Engineering, the students tested techniques to remove unwanted noise from the ECG signals while keeping diagnostic data intact so doctors can make treatment plans with accurate data.
“The problem is very challenging, but the students did a great job collaborating and developing a more accurate algorithm to separate noise from original ECG data,” says Mah'd.
The students learned from previously conducted research in the field that the interference is generated by “muscle artifacts,” which are signals from contractions caused by the ventricular assist devices.
Computer engineering major Michael Adams ’22 applied his expertise in programming and signal processing to help the team develop two techniques that could potentially eliminate the unwanted signals.
“Working with students from different disciplines helped us come up with the best solutions.” -Michael Adams ’22“Working with students from different disciplines helped us come up with the best solutions,” says Adams, who recently landed a job working as a product engineer in the field of radio frequency. He plans to work part time toward a master’s degree in computer engineering at UML.
One technique, called discrete wavelet transform, breaks down a noisy signal into a number of sets. Then the software finds the average to output a singular signal that most closely resembles what the heart signal may have looked like.
The second technique uses a generative adversarial network, a type of machine learning that can identify the signals coming from the device and rebuild the signal to represent only the signals produced by the heart.
The team accessed ECG databases from medical centers and open sources to test the algorithm. In the Biomedical Engineering ECG Lab at UML, the students collected their own dataset to validate the efficacy of the algorithm they developed.
The multidisciplinary team of students also included mechanical engineering major Benjamin Rhodes, electrical engineering major Shaniya Seney and computer engineering major HariGovind SundaraRaman.
“This project has been eye-opening to the process that goes into working in teams from multiple disciplines within the Francis College of Engineering,” says Palmer. “Each of us brings different skills to the project, from software development and technical writing to presenting our findings to our professors and the doctors at UMass Chan Medical School.”
Novel Approach to Preserving Livers for Transplants
Another capstone project team worked with researcher Julianna Buchwald, a UMass Chan Medical School M.D. and Ph.D. candidate, to develop a monitoring system to improve the preservation of livers for transplants. Buchwald works in the labs of Dr. Paulo Martins, a liver transplant surgeon, and Dr. Anastasia Khvorova, an expert in RNA drug delivery. Since September, she has met weekly with the student team.
Livers intended for transplantation are typically kept on ice, lasting up to 12 hours. However, cells suffer without fresh oxygen and blood. Due to injury sustained during the preservation period, about 10% of livers intended for transplants are discarded before making it to patients. Another way to keep livers functioning while outside the body is through a process called machine perfusion, a method of circulating fluids throughout a closed loop system.
The medical school is taking machine perfusion a step further by flowing RNA-based drugs through the system to prevent tissue damage to the organ.
“We needed the help of UMass Lowell engineering students to figure out an automated way to measure and adjust levels of liver parameters in real time,” says Buchwald.
Biomedical engineering major Elijah LaVancher ’22 and his team, working under the guidance of Biomedical Engineering Asst. Prof. Zhenglun (Alan) Wei, developed a feedback system that measures the acidity of the circulating fluid. The other team members included biomedical engineering majors Matthew Cavaco, Chresina Nhim and Shivam Patel.
The computer software calculates how much solution is needed and automatically administers it through a syringe, maintaining the pH level as close to the physiological environment as possible while the liver is connected to the device.
At the end of the academic year, the students visited the medical school to incorporate their components into the machine perfusion system and establish proof of concept.
“One of the most gratifying things was seeing a project go from early brainstorming to a full-fledged device that we could actually witness being used to advance the field of novel therapeutics,” says LaVancher. “Companies that I’ve interviewed with are impressed with my level of experience. With one offer in hand to work as an R&D engineer, I feel confident about my career choice due to the experience I gained at UMass Lowell.”