The potential role of feature tracking in adult congenital heart disease: advantages and disadvantages in measuring myocardial deformation by cardiovascular magnetic resonance

Cardiac magnetic resonance (CMR) imaging has several advantages over other imaging modalities in adult patients with congenital heart disease. Limitations remain however, in the assessment of myocardial function based on volumetric methods. There is increasing evidence in a range of diseases that myocardial strain is a more sensitive measure of regional and global ventricular contractile function. Feature tracking (FT), is a CMR-based method that measures strain without the need for additional sequence acquisition which can be analyzed rapidly, opening the possibility of use in adult congenital heart disease (ACHD). The aim of this review is to outline the technique of FT-CMR, its advantages and disadvantages compared to other techniques, review the values obtained, and to outline the preliminary data in support of its use in ACHD. In short, FT is a semi-automated post-processing technique that can be performed on routinely acquired images and thereby does not prolong scan time, is reproducible and not overly time-consuming. Although FT-CMR promises much, inevitably there remain limitations. While FT has excellent spatial resolution, temporal resolution is sub-optimal relative to speckle tracking echocardiography. FT-CMR is an emerging technique of measuring the myocardial strain that is comparable to speckle tracking echocardiography and the gold standard myocardial tagging CMR. FT-CMR derived strain parameters have potential diagnostic, risk stratification and prognostic value in the growing ACHD population.