Vendor independent myocardial strain values in children

Utilizing Artificial Intelligence-Based Deformable Registration for Global and Layer-Specific Cardiac MRI Strain Analysis in Healthy Children and Young Adults

RATIONALE AND OBJECTIVES

The absence of published reference values for multilayer-specific strain measurement using cardiac magnetic resonance (CMR) in young healthy individuals limits its use. This study aimed to establish normal global and layer-specific strain values in healthy children and young adults using a deformable registration algorithm (DRA).

MATERIALS AND METHODS

A retrospective study included 131 healthy children and young adults (62 males and 69 females) with a mean age of 16.6 ± 3.9 years. CMR examinations were conducted using 1.5T scanners, and strain analysis was performed using TrufiStrain research prototype software (Siemens Healthineers, Erlangen, Germany). Global and layer-specific strain parameters were extracted from balanced Steady-state free precession cine images. Statistical analyses were conducted to evaluate the impact of demographic variables on strain measurements.

RESULTS

The peak global longitudinal strain (LS) was -16.0 ± 3.0%, peak global radial strain (RS) was 29.9 ± 6.3%, and peak global circumferential strain (CS) was -17.0 ± 1.8%. Global LS differed significantly between males and females. Transmural strain analysis showed a consistent pattern of decreasing LS and CS from endocardium to epicardium, while radial strain increased. Basal-to-apical strain distribution exhibited decreasing LS and increasing CS in both global and layer-specific analysis.

CONCLUSION

This study uses DRA to provide reference values for global and layer-specific strain in healthy children and young adults. The study highlights the impact of sex and age on LS and body mass index on RS. These insights are vital for future cardiac assessments in children, particularly for early detection of heart diseases.

Permanent longitudinal strain damage of cardiotoxic drugs in childhood cancer: What is the safe level?

Objective

Anthracycline administration in children is associated with cardiac dysfunction. Speckle-tracking echocardiography (STE) can detect subclinical cardiac damage that may go undetected by conventional two-dimensional (2D) echocardiography. This study aims to investigate medium-term anthracycline cardiotoxicity using STE and determine a safer administrable level of anthracyclines (ACs).

Methods

This observational case-control study enrolled 37 healthy controls and 78 pediatric cancer survivors who received chemotherapy. The patients were divided into two groups: cardiotoxic received (CR) and cardiotoxic free (CF). Data on segmental longitudinal strain (LS), global LS (GLS), and 2D echocardiographic parameters were collected after a drug-free period of at least one year.

Results

A total of 115 children with a mean age of 108 ± 55 months, of whom 66% were males, were included in the study. Both the groups of cancer survivors exhibited significantly reduced GLS compared to healthy controls (CR vs. controls, P = 0.001; CF vs. controls, P = 0.013), but no significant difference in left ventricular ejection fraction (LVEF) was observed (P = 0.75). Overall, cancer survivors treated with ACs demonstrated a significant reduction in strain in 10 left ventricular segments, particularly in the basal segments (P < 0.05). Among CR patients, those with impaired GLS (n = 43, GLS worse than -21.9) had significantly higher mean age and cumulative anthracycline dose compared to CR patients with normal GLS (age, P = 0.024; anthracycline dosage, P = 0.036). Using an anthracycline cutoff of 223 mg/m2 resulted in a higher detection rate (49% vs. 25%) and fewer missed cases (51% vs. 74%) compared to the 360 mg/m2 anthracycline cutoff.

Conclusion

Childhood cancer survivors demonstrate significantly reduced GLS while preserving a normal LVEF, which does not differ significantly from reference values of healthy children. The reduction in strain appears to be associated with higher anthracycline doses and older age. Lowering the anthracycline threshold to 223 mg/m2 may improve the predictability of a decline in cardiac function using strain imaging at medium-term follow-up.