Grant to Help Sharif Develop Novel MRI Method

Behzad Sharif, PhD, is trying to make magnetic resonance imaging more useful for detecting ischemic heart disease.

Behzad Sharif, PhD, a research scientist in the Cedars-Sinai Department of Biomedical Sciences and Biomedical Imaging Research Institute (BIRI), has been awarded a $300,000 Scientist Development Grant by the American Heart Association. The four-year grant will support Sharif’s research on improving the effectiveness of magnetic resonance imaging (MRI) in detecting ischemic heart disease — the leading cause of death across the globe, according to the World Health Organization.

Cardiac MRI provides high-resolution, radiation-free imaging of myocardial perfusion, or blood flow in the heart muscle, at rest and during stress, as well as comprehensive assessment of cardiac structure and function. It has the potential for wide use for assessment of coronary artery disease. However, it currently plays a very small role in clinical practice due to technical challenges and limitations. Instead, nuclear imaging modalities, such as single photon emission computed tomography (SPECT), which require administration of a radioactive tracer material, are used.

According to Sharif, current myocardial perfusion MRI methods are lacking in reliability and image quality. Specifically, they may produce "image artifacts" that mimic heart disease, making it difficult to accurately determine whether disease is present in the patient. They also require data synchronization with an electrocardiogram, which reduces their reliability in case of changing heart rates during the exam.

Over the last two years, Sharif and collaborators at Cedars-Sinai have developed a "real-time" MRI data acquisition methodology that minimizes image artifacts and improves its reliability. Their method incorporates multiple disciplines, including: magnetic resonance physics, mathematical modeling, fast computational algorithms and cardiology.

Sharif's co-investigators include Debiao Li, PhD, director of BIRI; Rohan Dharmakumar, PhD, the institute's associate director; Daniel S. Berman, MD, director of cardiac imaging and medical director of BIRI and the Artificial Intelligence in Medicine program; and C. Noel Bairey Merz, MD, director of the Barbra Streisand Women's Heart Center and director of the Preventive and Rehabilitative Cardiac Center.

The American Heart Association grant will help the team test the hypothesis that ischemic heart disease can be accurately detected using the improved MRI method. "We believe that by eliminating the image artifacts and the need to synchronize the MRI data acquisition with an electrocardiogram signal, we can significantly improve the quality and robustness of cardiac MRI in detecting ischemic heart disease," said Sharif.

Sharif and his colleagues first tested the new MRI method on animal models of ischemic heart disease and also on healthy human volunteers. Once the method was validated, the researchers recruited volunteer patients with suspected heart disease, as indicated by a prior nuclear stress test. These patient studies are part of a pilot clinical trial that Sharif and Berman, his co-investigator, are conducting at BIRI.

"This grant will enable us to further develop our real-time MRI methodology and rigorously validate the imaging technique in animal models. The findings may potentially provide a solid foundation for translating the work into a diagnostic tool for patients with suspected ischemic heart disease," Sharif said.

According to its website, the American Heart Association's Scientist Development Grant program is designed to "support highly promising beginning scientists in their progress toward independence by encouraging and adequately funding research projects that can bridge the gap between completion of research training and readiness for successful competition as an independent investigator."
 

Panel shows cardiac perfusion images, which represent blood flow in the heart muscle for a patient with suspected ischemic heart disease, as generated by three different methods (l. to r.): newly developed "real-time" cardiac MRI method; conventional MRI technique used in current clinical practice; and a nuclear PET perfusion study. Arrows point to the blood flow deficit observed in the heart muscle.