Researchers at the Davis Heart and Lung Research Institute at Ohio State have discovered a new method for treating persistent atrial fibrillation, a condition that causes irregular heart beating. Credit: Asia Atuah | Lantern Reporter
A new technique discovered by Ohio State researchers may help better treat patients suffering from persistent atrial fibrillation, a condition causing an irregular heart beat.
Researchers at Ohio State’s Davis Heart and Lung Research Institute discovered that adenosine, a chemical present in human cells and commonly used in clinical practice, slowed electrical activity in the heart. Dr. John Hummel, director of clinical electrophysiology research at the Wexner Medical Center at Ohio State and leader of the clinical research, said the chemical allows doctors to pinpoint the exact location of causes of atrial fibrillation.
This concept was applied to a pilot clinical trial of 10 patients, according to an Oct. 8 press release.
Atrial fibrillation is the most common abnormal heart rhythm disorder and can cause strokes, heart failure, decline in cognition, significant decline in quality of life and increased likelihood of death, Hummel said. At least 2.7 million Americans have atrial fibrillation, according to the release.
Atrial fibrillation causes abnormal activity in the upper chambers of the heart. Normally, the chambers, called atria, have a steady electrical signal to allow for proper blood flow, but the condition prevents blood pumping and causes an irregular heart rhythm, Vadim Fedorov, professor of cell biology and physiology in the College of Medicine and lead author of the study, said.
Fedorov said many things can lead to these irregularities, including diabetes, obesity, heart failure and high blood pressure. Hummel said atrial fibrillation can be a temporary, occasional condition or can permanently afflict patients. Persistent atrial fibrillation requires intervention to normalize a patient’s heart rhythm.
Fedorov said when medicine cannot sufficiently treat persistent cases of atrial fibrillation, doctors will remove the heart tissue causing abnormal activity using a process called ablation. But even with current ablation tools, the complex layout of the heart makes targeting all faulty tissue difficult.
Working on human hearts donated for research by patients of Lifeline of Ohio and the Division of Cardiac Surgery at the Wexner Medical Center, researchers were also able to see a more holistic view of the heart. They injected a new, non-toxic fluorescent dye with electrical sensors into the atria and, using infrared cameras, were able to pinpoint more exact sources of abnormalities in the heart tissue than previously possible, Fedorov said.
“We have (the) ability to visualize electrical activity and not only panoramic, across both the right and left atria, but also transmural, which would lead to understanding of whole three-dimensional, electrical activity,” Fedorov said.
Fedorov said because continuous repetition of the ablation process eliminates error in determining sources of abnormal tissue, the treatment also creates the most accurate computer models of human atria to date.
“We can do this ablation procedure, but we can do it once by destroying tissue,” Fedorov said. “In (a) computer model, you can do ablation, then you can run again and do ablation in (a) different place and see whatever ablation would work best for this specific heart. So, you can simulate multiple, thousand different scenarios and define what would be the best treatment for this particular case.”
Fedorov said this new treatment option also takes into account the microstructure of each individual heart, which, akin to fingerprints, is unique.
“During disease, it will change differently. The scar will develop in different places in different [people] because not only of different disease, but because of different, natural microanatomy,” Fedorov said.
Fedorov said researchers’ next steps will be to apply the research clinically so that down the line, this treatment option may be directly applied to humans. He said researchers will also investigate how these abnormalities develop biologically so that they may prevent atrial fibrillation at its source.
The research was funded by the National Institutes of Health and the Bob and Corrine Frick Center for Heart Failure and Arrhythmia, Fedorov said.
