Between the Beats: Assessing New Technology to Measure Blood Flow
A new technology, bioelectric impedance cardiography (ZCG), which can assess blood flow in the chest to make inferences about heart function, may lead to an easier and less invasive way to identify heart problems. Now, with the help of the Health Sciences Emerging Scholars grant, George Washington University’s Josh Woolstenhulme, Ph.D., DPT, looks to prove the effectiveness of that technology.
Woolstenhulme, an assistant professor in the Department of Physical Therapy and Health Care Sciences at the School of Medicine and Health Sciences, explained that ZCG is different than traditional clinical tools used to assess heart function, such as the electrocardiogram (EKG), because it uses the electrical impedance of blood in the chest to determine how much blood is pumped out of the heart during each heart beat to make further inferences about heart function.
The primary focus of Woolstenhulme’s project is to validate the use of ZCG to assess diastolic function — the part of the heart cycle when the heart is between beats and filling with blood — while the patient is at rest, and also while he or she is exercising, Woolstenhulme said. Validating the ZCG technology for this specific purpose might enable clinicians to more easily identify the presence of diastolic dysfunction, which often precedes more advanced forms of cardiac dysfunction and in some disease populations can be a predictor of mortality.
“A lot of problems in the cardiorespiratory system may not manifest themselves while someone is sitting in a chair,” he said. “You have to actually get [people] exercising and pushing themselves to a higher activity level before you start seeing some of these problems arise. Measuring diastolic function during exercise is difficult with current technologies, so we’re hoping that this research project can help us understand if these newer ZCG devices can fill this critical gap by providing an easy-to-use, cost-effective alternative.”
Woolstenhulme added that he is excited to have the Emerging Scholars grant come through, especially if he is able to validate the use of ZCG to measure diastolic function and subsequently have it be used in future research projects and as a new tool for doctors.
“Its limitations notwithstanding, the ZCG technology is much cheaper and easier to use than echocardiography, which uses sound waves to visualize heart structures and blood flow, and if it’s actually a valid way to measure components of diastolic function, there may be a place to more fully adopt its use in research and in physician practices and clinics,” he said.