Diffusion MRI in the heart.

Area of Science:

• Cardiovascular Imaging
• Magnetic Resonance Imaging
• Biomedical Engineering

Background:

• Diffusion MRI provides crucial insights into myocardial tissue properties without exogenous contrast agents.
• Cardiac diffusion MRI faces challenges including cardiac and respiratory motion, signal inhomogeneity, and short T2 relaxation times.
• Recent advancements in accelerated diffusion-weighted MR sequences and post-processing have enhanced myocardial diffusion MRI accuracy and efficiency.

Purpose of the Study:

• To review solutions and approaches enabling in vivo cardiac diffusion MRI.
• To discuss the application of these techniques in evaluating myocardial structure and ischemic heart disease.
• To highlight the potential clinical translation of cardiac diffusion MRI.

Main Methods:

• Dual-gated stimulated echo approach.
• Velocity- (M1) or acceleration- (M2) compensated pulsed gradient spin echo approaches.
• Principal component analysis filtering for signal enhancement.

Main Results:

• Developed and reviewed techniques to overcome motion and signal challenges in cardiac diffusion MRI.
• Demonstrated improved accuracy and efficiency of diffusion MRI in the myocardium.
• Reviewed myocardial structure and applications in ischemic heart disease.

Conclusions:

• Cardiac diffusion MRI techniques have been developed to address technical challenges.
• Accelerated sequences and advanced post-processing improve accuracy and efficiency.
• Stronger clinical MR gradients will facilitate translation, adding a complementary tool for heart disease diagnosis.