Scripties UMCG - Rijksuniversiteit Groningen
English | Nederlands

Characterization and clinical significance of right ventricular mechanics in patients with repaired Tetralogy of Fallot: a cardiac magnetic resonance imaging study.

(2017) Vos, J.D.L. (Johannes)

Aims Patients with tetralogy of Fallot (ToF) generally suffer from pulmonary
regurgitation (PR) and/or residual pulmonary stenosis (PS) after surgical repair.
Regular cardiac assessment is required to evaluate right ventricular (RV)
adaptation and function in response to the abnormal loading conditions.
However, global measures such as RV ejection fraction (RVEF) may not be
sensitive enough to detect subtle changes in RV function. Feature tracking
cardiac magnetic resonance (FT-CMR) analysis is a novel post-processing
technique allowing for regional quantification of myocardial deformation on
standard CMR images. This study was designed to evaluate the effect of RV
dimensions (volumes and mass) to deformation patterns obtained by FT-CMR
and to compare with ejection fraction.
Methods Cardiac magnetic resonance imaging data were retrospectively analyzed.
We assessed the associations between RV deformation and RV volumes, mass
and function.
Results CMR images of 158 subjects were analyzed. RV end-diastolic volume indexed
for body surface area (RVEDVi) correlated with RVEF only (r=-0.220,
p<0.01). RV end-systolic volume index (RVESVi) correlated with RVEF (r=-
0.630, p<0.001), global circumferential strain (RVGCS) (r=0.352, p<0.001),
circumferential systolic strain rate (RVCSRsystolic) (r=0.290, p<0.001) and
diastolic strain rate (RVCSRdiastolic) (r=-0.274, p<0.001). RV mass index
(RVMi) correlated with RVEF (r=-0.187, p<0.05), RV global longitudinal
strain (RVGLS) (r=0.190, p<0.05), RV free wall systolic (RVLSRfree_wall_systolic)
(r=0.225, p<0.01) and diastolic strain rate (RVLSRfree_wall_diastolic) (r=0.337,
p<0.001). RV mass/volume ratio (RVM/V) expressed correlations with
RVGLS (r=0.335, p<0.001), RVLSRfree_wall_systolic (r=0.291, p<0.001) and
RVLSRfree_wall_diastolic (r=-0.286, p<0.001) but not with RVEF. RVEF correlated
with RVGLS (r=-0.351, p<0.001), RVLSRfree_wall_systolic (r=-0.192, p<0.05),
RVLSRfree_wall_diastolic (r=0.222, p<0.01), RVGCS (r=-0.488, p<0.001),
RVCSRsystolic (r=-0.349, p<0.001), RVCSRdiastolic (r=-0.346, p<0.001).
Conclusion FT-CMR analysis is a feasible and highly reproducible technique for
quantifying myocardial contractility and provides better accuracy compared to
ejection fraction. Absolute regional strain values are associated with EF,
ventricular mass, mass/volume ratio and end-systolic volume and can alter
independent of changes in EF. Therefore it is a highly potential technique for
evaluating cardiac function and changes in contractility over time during the
follow-up of patients with rToF.

To top