Programa del congreso

1. Introduction

Global longitudinal strain (GLS) is the guideline-recommended gold standard for detecting subclinical cardiotoxicity in cancer patients, with a relative decline greater than 10-15% serving as an early warning sign of myocardial dysfunction [1].

However, cardiotoxicity presents as a spectrum of myocardial injury that may affect distinct cardiomyocyte orientations at different stages depending on the therapeutic agent.

Beyond the well-characterized anthracycline-mediated GLS decline, myocarditis-like toxicity associated with immune checkpoint inhibitors and other immunotherapies may primarily involve mid-wall circumferential cardiomyocytes [1,2]. In such scenarios, global circumferential strain (GCS) may decrease earlier than GLS.

Although GCS has generally excellent reproducibility when assessed by cardiac magnetic resonance (CMR), its echocardiographic assessment remains technically challenging, espcially in children.

2. Methodology and Results

We therefore propose circumferential fractional shortening (cFS) as a practical surrogate marker for GCS. Derived from M-mode recordings in the parasternal long-axis view, cFS is a modified form of conventional fractional shortening (FS) that excludes the influence of radial thickening, thus isolating circumferential myocardial contractility (see Equation 1).

cFS(%) = 100 · (LVEDD - LVESD') / LVEDD

where LVESD' = LVESD + ∆wall, LVEDD and LVESD are the left ventricular (LV) internal minor-axis diameters at end diastole and end systole, respectively, and ∆wall is the change in wall thickness (calculated as the sum of the differences in wall thickness between end systole and end diastole for both the interventricular septum and the LV posterior free wall).

Applied to our longitudinal pediatric cardio-oncology cohort, cFS was computed in 64% of the patients, with the remaining excluded due to measurement errors. Although GCS data were not available for comparison yet, subsequent analysis will aim to measure GCS and assess its correlation with cFS.

3. Conclusion

Given the limitations in measuring GCS via conventional echocardiography and the evolving cancer therapy landscape, if we could demonstrate significant correlations between GCS and cFS, cFS would represent a promising, more accessible measure of circumferential dysfunction, aiding in the early recognition of diverse cardiotoxic injury phenotypes.

References

[1] A. R. Lyon et al., "2022 ESC Guidelines on cardio-oncology developed in collaboration with the European Hematology Association (EHA), the European Society for Therapeutic Radiology and Oncology (ESTRO) and the International Cardio-Oncology Society (IC-OS)",
European Heart Journal - Cardiovascular Imaging, vol.23, no.10, pp.e333-e465, 2022.

[2] T. Quinaglia et al, "Global Circumferential and Radial Strain Among Patients With Immune Checkpoint Inhibitor Myocarditis", JACC: Cardiovascular Imaging, vol. 15, no. 11, pp. 1883-1896, 2022.

Acknowledgements

SMT has received funding from the Doctorats Industrials de la Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement de la Generalitat de Catalunya (2024 DI 0137). This study was partially funded by the Spanish Ministry of Science and Innovation, MCIN/AEI/10.13039/501100011033, under the Maria Maetzu Unit of Excellence Programme (CEX2021-001195-M) and by the European Commission–“NextGenerationEU” (Ref. TED2021-132025B-C44). PGC acknowledges support from the grant #RYC2023-043724-I by MCIU/AEI/10.13039/501100011033 and from FSE+.