Purpose
In patients with repaired tetralogy of Fallot, transcatheter or surgical pulmonary valve replacement is recommended. However, it is not clear whether pulmonary valve replacement preserves systolic and diastolic functions of both ventricles. The aim of the study is to investigate the impact of transcatheter pulmonary valve replacement on atrial and ventricular myocardial strain changes by feature-tracking cardiac magnetic resonance imaging.
Materials and methods
Cardiac magnetic resonance imaging of 18 patients (median age 14.5 years) with repaired tetralogy of Fallot before and after transcatheter pulmonary valve replacement were retrospectively analyzed. Feature tracking strain for both left and right atria and ventricles was performed. Cardiac magnetic resonance imaging parameters (volume and function) and strain characteristics (atria and ventricles) were compared before and after transcatheter pulmonary valve replacement. The Wilcoxon rank-sum and Spearman correlation test was used.
Results
After pulmonary valve replacement, right ventricular end-diastolic volume, end-systolic volume, and stroke volume decreased, whereas left and right ventricular ejection fractions remained unchanged. Reservoir, conduit and pump strain measurements improved for both left (P = 0.003, P = 0.001, and P = 0.006) and right atria (P = 0.013, P = 0.004, and P = 0.015). Global left ventricular circumferential, longitudinal, and radial strains improved (P = 0.001, P = 0.043, and P = 0.002, respectively). Right ventricle global circumferential strain significantly improved with no significant change in the longitudinal and radial strains (P = 0.007, P = 0.068, and P = 0.055, respectively).
Conclusion
Transcatheter pulmonary valve replacement significantly enhances atrial and ventricular strain parameters, indicating a positive impact on overall myocardial function. Feature-tracking cardiac magnetic resonance imaging may offer a comprehensive, non-invasive evaluation of myocardial strain changes in patients with repaired tetralogy of Fallot after pulmonary valve replacement, which leads to improvement of indications and outcomes.
