HeRO News

Pilot Funding Report: Cardiac Fiber Imaging Using Ultrasound and DTI

Cardiac Fiber Imaging Using Ultrasound and DTI
PI: Baowei Fei, Ph.D.
2014 HeRO Pilot Award  

Cardiac fibers directly affect the mechanical, physiological and pathological properties of the heart. Heart failure (HF) is a leading cause of hospitalization, death, and disability in most developed countries, creating a significant social and economic burden for patients, families, and health care systems. Abnormal cardiac fiber orientations such as those in heart failure patients directly affect cardiac function such as ejection fraction, and also contribute to arrhythmias that can lead to sudden death. Cardiac fiber mapping allows us to study the development and progression of cardiac diseases in individuals as well as provides insight into the mechanism of cardiac failure. Innovative imaging technology for early detection of heart failure can have a significant impact on the management of this disease that affects more than 5 million Americans.

Imaging and quantification of cardiac fiber orientations is a challenging task. As compared to the brain where magnetic resonance diffusion tensor imaging (MR-DTI) technology has been successfully developed to visualize brain fiber orientations, it is more difficult to directly measure the cardiac fiber orientations of a beating heart because of motion artifacts. On the other hand, cardiac ultrasound or echocardiography has become one of the most widely utilized modalities in cardiac imaging. Each year approximately 20% of enrollees in the fee-for-service system receive at least one echocardiogram. The number of echocardiography procedures by Medicare beneficiaries is 7 million each year. Unfortunately, echocardiography does not currently have the capability of estimating cardiac fiber orientations. This research developed novel and cost-effective imaging tools for early detection of heart failure, which can have a significant impact on the clinical management of millions of patients with heart diseases.

This pilot research developed imaging tools to measure cardiac fiber orientations based three-dimensional (3D) ultrasound. We hypothesized that cardiac fiber orientation can be indirectly estimated through the 3D ultrasound geometry of a patient's heart based on a cardiac fiber atlas from MR-DTI. In this study, we tested the hypothesis in in vivo beating hearts. This research is the first study that combines MR-DTI fiber atlas information with real-time 3D ultrasound to study heart failure. Some of our results are published in Medical Physics, Physics in Imaging and Biology, and SPIE Medical Imaging.