Title:Real-time Strain-encoding Cardiovascular MRI for Assessment of Regional
Heart Function in Tetralogy of Fallot Patients
Volume: 20
Author(s): El-Sayed H. Ibrahim*, Prachi P. Agarwal, Maryam Ghadimi-Mahani, Jadranka Stojanovska, Antonio Sosa, Adam L. Dorfman and Jimmy C. Lu
Affiliation:
- Department of Radiology, Medical College of Wisconsin, Milwaukee, Wisconsin, WI, 53226, USA
Keywords:
Tetralogy of fallot, FastSENC, MRI, Right ventricle, Heart, Strain.
Abstract:
Background:
Tetralogy of Fallot (ToF) is the most common form of cyanotic congenital heart disease, where right ventricular (RV) function is an important
determinant of subsequent intervention.
Objective:
In this study, we evaluate the feasibility of fast strain-encoding (fastSENC; a one-heartbeat sequence) magnetic resonance imaging (MRI) for
assessing regional cardiac function in ToF.
Methods:
FastSENC was implemented to characterize regional circumferential (Ecc) and longitudinal (Ell) strains in the left ventricle (LV) and RV in postrepair
ToF. Data analysis was conducted to compare strain measurements in the RV to those in the LV, as well as to those generated by the MRI
Tissue-Tracking (MRI-TT) technique, and to assess the relationship between strain and ejection fraction (EF).
Results:
Despite normal LVEF (55±8.5%), RVEF was borderline (46±6.4%), but significantly lower than LVEF. RV strains (RV-Ell=-20.2±2.9%, RVEcc=-
15.7±6.4%) were less than LV strains (LV-Ell=-21.7±3.7%, LV-Ecc=-18.3±4.7%), and Ell was the dominant strain component. Strain
differences between fastSENC and MRI-TT were less significant in RV than in LV. There existed moderate and weak correlations for RV-Ecc and
RV-Ell, respectively, against RVEF. Compared to LV strain, RV strain showed regional heterogeneity with a trend for reduced strain from the
inferior to anterior regions. Inter-ventricular strain delay was larger for Ell (64±47ms) compared to Ecc (36±40ms), reflecting a trend for
contraction dyssynchrony.
Conclusion:
FastSENC allows for characterizing subclinical regional RV dysfunction in ToF. Due to its sensitivity for evaluating regional myocardial
contractility patterns and real-time imaging capability without the need for breath-holding, fastSENC makes it more suitable for evaluating RV
function in ToF.
