Conditions such as heart attacks, low blood pressure or oxygen, and extreme heart rates can demand more resources than the heart’s usual metabolic rate can handle, causing severe heart injury. While medicine can improve protection of the cardiovascular system against these injuries, exercise serves as an additional cardioprotection method for people with severe heart failure who are unresponsive to medication.

Unfortunately, for people with health conditions, exercise, which requires the use of several different organ systems, is not always a tolerated or a safe option.

Denice Hodgson-Zingman, MD, associate professor in cardiovascular medicine and of biomedical engineering, received a two-year, $433,146 R21 NIH grant. Hodgson-Zingman’s proposed research focuses on heart rate acceleration patterns and cardioprotection during exercise.

During previous research, Hodgson-Zingman and Co-PI Leonid Zingman, MD, associate professor in cardiovascular medicine, were able to reproduce an exercise heart rate pattern by pacing the top heart chambers of mice once daily for several weeks at a time. The treatment was successful and the hearts of the mice who had been treated showed molecular changes reminiscent of those known to occur with exercise and the hearts responded better to periods of decreased oxygen than the hearts of mice who were not treated.

“As a clinical cardiac electrophysiologist, I realized that we had a rare opportunity to test these ideas simultaneously and safely in human subjects and thereby directly assess the potential for therapeutic translation,” Hodgson-Zingman said.

Using a randomized group of subjects, Hodgson-Zingman used the already implanted defibrillators in people with heart disease to pace their heart rate in an exercise-like pattern over a period of a month. Compared to a control group, Hodgson-Zingman’s data suggested that this intervention improved the heart’s function and their quality of life.

With this funding, Hodgson-Zingman and Zingman will be able to expand on both the mouse and human heart rate research to see if this therapy should be officially adopted to improve the quality of life for people with heart disease.

“Leonid Zingman and I were delighted to receive this award,” Hodgson-Zingman said. “We hope that the new data obtained under this award will allow us to further refine our hypotheses about cardioprotection and lead to new targets for therapeutic intervention.”

In addition to the help from Leonid Zingman, Hodgson-Zingman also received assistance from Chad Greuter, PhD, assistant professor in cardiovascular medicine, and Donna McClish, PhD, professor of biostatistics at Virgina Commonwealth University.