Value of cardiac MRI in evaluation of left atrial function in the postoperative tetralogy of Fallot and pulmonary stenosis patients / 中华放射学杂志

ABSTRACT

Objective:To explore the value of cardiac MRI (CMRI) in evaluating left atrial function in patients with postoperative tetralogy of Fallot (rTOF) and postoperative pulmonary stenosis (rPS).Methods:Totally 67 pediatric patients (49 with rTOF, 18 with rPS) with preserved left ventricular ejection fraction (EF) were recruited between January 2019 and October 2021 in Shanghai Children′s Medical Center, School of Medicine, Shanghai Jiao Tong University. Thirty-three healthy volunteers, matched in gender and age, were included as controls from July 2017 to August 2018. Left atrial EF, strain and strain rate of three phases (reservoir, conduit and pump), left atrial volume (maximum volume index, minimum volume index and pre-atrial contraction volume index) were measured with corresponding cardiac function analysis software. Then, the differences in these parameters were analyzed between the three groups by ANOVA or Kruskal-Wallis test with post hoc comparison and Bonferroni correction.Results:Compared with controls, patients with rTOF had lower reservoir function parameters (EF, strain and strain rate), conduit EF, conduit strain, and left atrial maximum volume index ( P<0.05), but higher pump EF ( P<0.05). In patients with rPS, only the reservoir strain rate decreased compared with controls ( P<0.05), and the remaining data showed no significant difference ( P>0.05). The reservoir and conduit EF and strain in patients with rPS were higher than those in patients with rTOF ( P<0.05). Conclusions:In patients with rTOF and rPS, left atrial function has changed despite the preservation of left ventricular EF, which may be an early marker of left ventricular diastolic dysfunction. In children with rTOF, left atrial reservoir and conduit functions decreased while the pump function increased. The reservoir and pump functions in rPS were better than those in rTOF. In addition, CMRI can detect left atrial dysfunction early before it enlarged.