Diffusion Tensor Cardiovascular Magnetic Resonance Imaging

Abstract

Imaging the heart is central to cardiac phenotyping but in clinical practice this has been restricted to macroscopic interrogation. Diffusion tensor cardiovascular magnetic resonance (DT-CMR) is a novel, non-invasive technique which is beginning to unlock details of this microstructure in humans in-vivo. DT-CMR demonstrates the helical cardiomyocyte arrangement that drives rotation and torsion. Sheetlets (functional units of cardiomyocytes, separated by shear layers) have been shown to reorientate between diastole and systole, revealing how microstructural function facilitates cardiac thickening. Measures of tissue diffusion can also be made; fractional anisotropy (a measure of myocyte organisation) and mean diffusivity (a measure of myocyte packing). Abnormal myocyte orientation and sheetlet function has been demonstrated in congenital heart disease, cardiomyopathy and after myocardial infarction. It is too early to predict the clinical importance of DT-CMR, but such unique in-vivo information will likely prove valuable in early diagnosis and risk prediction of cardiac dysfunction and arrhythmias.

Cardiac magnetic resonance imaging: insights into developmental programming and its consequences for aging

“…A more advanced approach, diffusion tensor CMR (DT-CMR), can be used to evaluate myocyte orientation and sheetlet function, however this a technically challenging method. 52 New approaches that combine improved spatial and angular resolution with greater scanning speed and increased coverage may allow DT-CMR to become a routine research tool in the near future. The power of sampling myocardial tissue at necropsy in animal models of developmental programming can be used to correlate features such as fibrosis with in vivo images of the tissue structure.…”

Cardiovascular Magnetic Resonance for the Differentiation of Left Ventricular Hypertrophy

“…Diffusion tensor imaging (DTI) is an emerging CMR technique that may provide important insights into hypertrophic disease processes by characterising myocardial microstructural changes [33]. It can assess cardiomyocyte fibre orientation and packing (and hence myofibrillar disarray), by mapping the three-dimensional diffusion of water molecules [33, 34, 35•].…”

“…Diffusion tensor imaging (DTI) is an emerging CMR technique that may provide important insights into hypertrophic disease processes by characterising myocardial microstructural changes [ 33 ]. It can assess cardiomyocyte fibre orientation and packing (and hence myofibrillar disarray), by mapping the three-dimensional diffusion of water molecules [ 33 , 34 , 35 •]. The ability to detect microstructural changes in hypertrophic diseases may help differentiate pathological from physiological hypertrophy (expected to have normal myocardial architecture).…”

Editorial for “Insight Into Myocardial Microstructure of Athletes and Hypertrophic Cardiomyopathy Patients Using Diffusion Tensor Imaging”

“…C ardiac diffusion tensor imaging (DTI) has seen great advances in the past decade. 1 Due to the technical challenge of performing motion-sensitive DTI on a beating heart, only a handful of articles were published from 1994 2 to 2012. With recent advances in magnetic resonance imaging (MRI) hardware and sequences, more than two dozen cardiac DTI studies have been reported since 2012.…”

“…Cardiac diffusion tensor imaging (DTI) has seen great advances in the past decade 1 . Due to the technical challenge of performing motion‐sensitive DTI on a beating heart, only a handful of articles were published from 1994 2 to 2012.…”