Impact of surgical pulmonary valve replacement on ventricular mechanics in children with repaired tetralogy of Fallot

Abstract

Impaired ventricular myocardial mechanics are observed in patients with repaired tetralogy of Fallot (rTOF). Effects of pulmonary valve replacement (PVR) on ventricular remodeling are controversial. The objective was to assess the impact of surgical PVR on ventricular mechanics in pediatric patients after rTOF. Speckle-tracking analysis was performed in 50 rTOF children, aged 12.6 ± 3.3 years, pre-operatively and 14.5 ± 2.2 months post-PVR. Early post-operative studies 2.2 ± 0.6 months post-PVR were performed in 28 patients. Cardiac magnetic resonance (CMR) pre- and post-PVR was collected. Mid-term post-PVR right ventricular (RV) longitudinal strain increased above pre-operative strain (-19.2 ± 2.7 to -22.0 ± 3.0%, p < 0.001) with increases observed in individual RV segments. Left ventricular (LV) strain did not differ at medium-term follow-up. LV and RV longitudinal strain was reduced early post-operatively, followed by recovery of biventricular systolic strain by mid-term follow-up. CMR RV end-diastolic indexed volumes correlated with RV strain pre-operatively (r = 0.432, p = 0.005) and at mid-term follow-up (r = 0.532, p = 0.001). Volume-loaded RVs had reduced early RV basal longitudinal strain compared to pressure-loading conditions. Reversed basal counterclockwise rotation was associated with lower mid-term global LV and basal RV strain compared to patients with normal rotation. An increase in mid-term global and regional RV strain beyond pre-operative values suggests positive RV remodeling and adaptation occurs in children post-PVR. Patients with larger pre-operative RV volumes had lower RV strain post-operatively. The impact of LV rotation on RV mechanics highlights the presence of ventriculo-ventricular interactions. These findings have important clinical implications in pediatric rTOF patients towards identifying pre-operative factors that predict RV post-operative remodeling.

Assessment of right ventricular systolic function in children with repaired tetralogy of Fallot by multiple‐view from single acoustic window with speckle tracking echocardiography

“…Accurate assessment of RV function is important for the management of children with rTOF . Through combined novel echocardiographic modalities of multi‐view analysis and STE, a deeper understanding of RV can be attained.…”

“…Therefore, RV functional assessment in children with rTOF is of great clinical significance. It helps to judge the prognosis and to determine the optimal timing of the possible postoperative medication or second‐time surgery for RV recovery …”

Posicionamento sobre Indicações da Ecocardiografia em Cardiologia Fetal, Pediátrica e Cardiopatias Congênitas do Adulto – 2020

“…Alguns autores encontraram correlação negativa entre o strain de pico sistólico longitudinal de VD e fração de ejeção do VD e fração de regurgitação pulmonar, ambas estimadas pela RM. 132 Outros trabalhos documentaram correlação negativa entre o strain longitudinal do VE e o grau de regurgitação pulmonar, reforçando a importância da interdependência entre os ventrículos. 133 Ainda que o estudo da deformação miocárdica consiga detectar disfunção sistólica subclínica nos pacientes operados de T4F que evoluem com regurgitação pulmonar, infelizmente, não há consenso quanto a um valor de corte de strain que permita indicar o melhor momento para a troca valvar pulmonar.…”

Applications of the Myocardial Strain Study using Two-Dimensional Speckle Tracking in Pediatrics

“…Alguns autores encontraram correlação negativa entre o strain de pico sistólico longitudinal de VD e fração de ejeção do VD e fração de regurgitação pulmonar − ambas estimadas pela RMC. 37 Outros trabalhos documentaram correlação negativa entre o strain longitudinal do VE e o grau de regurgitação pulmonar, reforçando a importância da interdependência entre os ventrículos. 38 Ainda que o estudo da deformação miocárdica consiga detectar disfunção sistólica subclínica nos pacientes operados de T4F que evoluem com regurgitação pulmonar, infelizmente não há consenso quanto a um valor de corte de strain que permita indicar o melhor momento para a troca valvar pulmonar.…”