Left atrial strain abnormalities and history of life-threatening arrhythmia in corrected tetralogy of Fallot : A cardiac MRI analysis

Introduction

The objectives of this study were to examine left atrial (LA) function using cardiac MRI analysis in adult patients with corrected Tetralogy of Fallot (c-ToF) and to investigate the relationships between LA reservoir function and patient characteristics, especially history of life-threatening arrhythmia ((h-LTA) including sustained and non sustained ventricular tachycardia.

Method

39 c-ToF patients (27 males; age: 39 ± 15 years; h-LTA, n = 10) were included in this retrospective monocenter study. In addition to a standard cardiac MRI examination, LA strain analysis was performed to assess LA volume and function, including peak-positive LA strain (LAS-reservoir function).

Results

Patients with h-LTA tend to be older (46 ± 17years vs. 39 ± 13 years; p = 0.06); had more history of pulmonary valve replacement (40% vs. 24%; p = 0.03) and exhibited a significant longer QRS duration (167 ± 19 ms vs. 142 ± 25 ms; p < 0.001).

LAS was significantly lower in the group of patients with h-LTA (12.9 ± 4% vs. 17.9 ± 4.6%; p = 0.01) while others MRI parameters, including left/right ventricular function and volumes, right atrial volumes and late gadolinium enhancement, did not differed between two groups.

Moderate inverted correlation was found between LAS and QRS duration (−0.43; p = 0.005). Among tested parameters, LAS was the best predictor for h-LTA (AUC: 0.838; p < 0.001) especially best than QRS duration.

Analysis of intraobserver and interobserver variability demonstrated good agreement between observations for the LAS [ICC (95% confidence interval): 0.97 (0.94–0.98) and 0.84 (0.44–0.96), respectively]

Conclusion

Using cardiac MRI, we documented abnormal LA reservoir function in adult c-ToF patients. Further study is needed to determine how best to incorporate LAS reservoir function assessed by MRI, into multiparametric predictive models for LTA in c-ToF patients.