Native Myocardial T1 Mapping, Are We There Yet?

Area of Science:

• Cardiovascular Imaging
• Biomedical Engineering
• Radiology

Background:

• T1 relaxation time is a fundamental MRI parameter for tissue characterization.
• Myocardial T1 mapping has matured as a cardiac magnetic resonance (CMR) technique.
• Pixel-based mapping and shorter acquisition times have improved T1 quantification.

Purpose of the Study:

• To review the advancements and clinical applications of T1 mapping in the myocardium.
• To discuss the methods and challenges associated with T1 quantification.
• To highlight the potential of T1 mapping as a biomarker for diffuse myocardial diseases.

Main Methods:

• Utilizes inversion recovery (e.g., MOL-LI, ShMOLLI) and saturation recovery (e.g., SASHA) sequences for T1 quantification.
• Evolved from region of interest analysis to pixel-based parametric mapping.
• Employs short breath-hold sequences for improved patient tolerance and data acquisition.

Main Results:

• Native T1 values change predictably with myocardial conditions like edema, fibrosis, fat, and iron.
• T1 mapping demonstrates high sensitivity and specificity for diffuse myocardial diseases.
• It serves as a potential disease biomarker and prognostic predictor.

Conclusions:

• T1 mapping is a valuable tool for characterizing myocardial tissue, especially in diffuse diseases.
• Further standardization of normal values and acquisition techniques is required for broader clinical adoption.
• Continued development of analysis tools will enhance the utility of T1 mapping in cardiology.