Left Ventricular Strain and Strain Rate during Submaximal Semisupine Bicycle Exercise Stress Echocardiography in Childhood Cancer Survivors

Background: Childhood cancer survivors (CCSs) show relevant cardiac morbidity and mortality throughout life. Early detection of cardiac dysfunction is key for optimal support of patients at risk. 2D-speckle-tracking strain echocardiography (STE) and stress echocardiography may help to identify subclinical cardiac dysfunction. Aim of this study was to evaluate 2D-STE strain analysis during semisupine exercise stress in CCSs for detection of subclinical left-ventricular (LV) dysfunction after childhood cancer treatment.

Method: A total of 77 CCSs ≥1 year postchemotherapy were prospectively examined according to a standardized stress protocol at rest, low and submaximal stress level, and compared with a previously established control group (n = 50) of healthy adolescents and young adults. Image acquisition was optimized for strain analysis. Global longitudinal strain (GLS), short-axis circumferential strain (CS), and corresponding strain rates (SR) were analyzed using vendor-independent software.

Results: CCSs at a median of 7.7 years post chemotherapy showed comparable LV GLS, CS, and SR values during rest and low and submaximal exercise stress level to healthy controls. Yet, prevalence of abnormal GLS (defined as <2 SD of controls reference) in CCSs was 1.3% at rest, 2.7% at low, and 8.6% at submaximal stress. In CCSs relative change of CS from rest to submaximal stress was lower than in healthy controls, median of 16.9 (IQR: 3.4; 28.8)% vs. 23.3 (IQR: 11.3; 33.3)%, p = 0.03. This was most apparent in the subgroup of CCSs after high-dose anthracycline treatment and in the subgroup of CCSs with cancer diagnosis before age of 5 years.

Conclusion: In this prospective 2D-STE strain study, prevalence of abnormal LV-GLS increased with stress level reflecting impaired cardiac adaption to exercise stress in some CCSs.

However, relatively early, after last chemotherapy, this did not result in significant differences of mean GLS, CS, and SR values between CCSs and controls at any stress level. Considering our results, 2D-STE exercise stress–strain analysis may be an interesting add-on to routine cardiooncologic surveillance. This project had been supported by the DGPK.

Publication History

Article published online:
12 February 2022