Impact of pulmonary valve replacement on left ventricular rotational mechanics in repaired tetralogy of Fallot

Abstract

Background In repaired tetralogy of Fallot (rTOF), abnormal left ventricular (LV) rotational mechanics are associated with adverse clinical outcomes. We performed a comprehensive analysis of LV rotational mechanics in rTOF patients using cardiac magnetic resonance (CMR) prior to and following surgical pulmonary valve replacement (PVR). Methods In this single center retrospective study, we identified rTOF patients who (1) had both a CMR ≤ 1 year before PVR and ≤ 5 years after PVR, (2) had no other intervening procedure between CMRs, (3) had a body surface area > 1.0 m2 at CMR, and (4) had images suitable for feature tracking analysis. These subjects were matched to healthy age- and sex-matched control subjects. CMR feature tracking analysis was performed on a ventricular short-axis stack of balanced steady-state free precession images. Measurements included LV basal and apical rotation, twist, torsion, peak systolic rates of rotation and torsion, and timing of events. Associations with LV torsion were assessed. Results A total of 60 rTOF patients (23.6 ± 7.9 years, 52% male) and 30 healthy control subjects (20.8 ± 3.1 years, 50% male) were included. Compared with healthy controls, rTOF patients had lower apical and basal rotation, twist, torsion, and systolic rotation rates, and these parameters peaked earlier in systole. The only parameters that were correlated with LV torsion were right ventricular (RV) end-systolic volume (r = − 0.28, p = 0.029) and RV ejection fraction (r = 0.26, p = 0.044). At a median of 1.0 year (IQR 0.5–1.7) following PVR, there was no significant change in LV rotational parameters versus pre-PVR despite reductions in RV volumes, RV mass, pulmonary regurgitation, and RV outflow tract obstruction. Conclusion In this comprehensive study of CMR-derived LV rotational mechanics in rTOF patients, rotation, twist, and torsion were diminished compared to controls and did not improve at a median of 1 year after PVR despite favorable RV remodeling.

Impact of pulmonary valve replacement on left and right ventricular function using strain analysis, in children with repaired tetralogy of Fallot

“…In contrast, in Harrington’s study in 2021, CMR-derived LV rotational mechanics in rTOF patients including rotation, twist, and torsion were diminished compared to control and did not improve at a median of 1 year after PVR despite favorable RV remodeling [ 26 ]. So was there in Beatrice Monti’s study, in which both global and segmental RV strains increased over time in patients undergone PVR as in patients who did not, and yearly variations did not differ significantly between groups [ 27 ].…”

Ventricular Dyssynchrony Late after the Fontan Operation is Associated with Decreased Survival and the Presence of Arrhythmias

“…Feature tracking analysis was performed on the short-axis cine stack of images as previously described. 21 Briefly, the endocardial and epicardial borders were manually traced at end-diastole for all slices from the apex to base of the dominant ventricle in the case of a single LV or single RV. For mixed-type ventricles, borders were traced around both ventricles (excluding the ventricular septum).…”

Single Ventricular Torsional Mechanics After Fontan Palliation and Their Impact on Outcomes

“…FT analysis was performed on the short-axis cine stack of images using a commercially available software (cvi42, Circle Cardiovascular Imaging Incas previously described. 14 Briefly, the endocardial and epicardial borders were manually traced at end-diastole for all slices from the apex to the base of the ventricle and contours were manually adjusted to ensure adequate tracking. The apical slice was defined as the most apical slice with blood pool throughout the entire cardiac cycle.…”