Cardio-Oncology: Monitoring Cardiotoxicity via EchoCG and GLS — When Reduction is Significant
According to BSE/BCOS (2021) guidelines for patients receiving anthracyclines and/or trastuzumab, monitoring is conducted via EchoCG (by default every 3 months) with mandatory assessment of 2D/3D LVEF and GLS. It is advisable to consider referral to a specialist before starting therapy; patients with pre-existing systolic LV dysfunction should be discussed with the cardio-oncology team, ideally before the start of cardiotoxic therapy.
Criteria for Significant Change (BSE/BCOS, 2021)
| Category | Criterion |
|---|---|
| Cardiotoxicity | Reduction in LVEF by >10 absolute percentage points to a value <50% |
| Cardiotoxicity | Reduction in LVEF by >10 absolute percentage points to a value ≥50% with a concurrent GLS drop >15% |
| Probable Subclinical Cardiotoxicity | Reduction in LVEF by <10 absolute percentage points to a value <50% |
| Possible Subclinical Cardiotoxicity | Relative reduction in GLS >15% from baseline |
Role of GLS
There is growing evidence that a significant reduction in GLS accurately predicts subsequent cardiotoxicity (BSE/BCOS, 2021). With a relative reduction in GLS >15% against a background of normal LVEF, referral to a cardio-oncology service for expert evaluation can be considered. LV strain assessment using 2D speckle-tracking (STE) should be performed according to accepted standards.
It is important to consider the "gray zone": normal GLS may indicate potential subclinical cardiotoxicity, but in some cases reflects normal physiological variability (BSE/BCOS, 2021).
Monitoring Organization
A personalized approach to serial assessment is recommended; targeted cardio-oncological EchoCGs are performed within the scope of the full minimum BSE protocol with cardio-oncological measurements. All patients with confirmed cardiotoxicity require referral to a cardio-oncology service.
Method Limitations
In cases of rhythm disturbances, serial assessment may be challenging. In atrial fibrillation, due to constant variability in cardiac cycle duration, systolic and diastolic ventricular function indicators may have limited reliability.
Features in Children
In children, the potential benefit of STE during antitumor treatment for detecting acute cardiotoxicity has been studied in various studies involving a relatively small number of patients (ASE, 2023). The acute effect of anthracycline infusions manifested as an increase in myocardial wall thickness and a decrease in radial and longitudinal strain values. With borderline or pathological GLS and preserved LVEF, more frequent monitoring may be indicated, although supporting data is currently lacking.
Frequently asked questions
What relative reduction in GLS is considered significant?
A relative reduction in GLS >15% from baseline (BSE/BCOS, 2021) is a criterion for possible subclinical cardiotoxicity.
How is clinical cardiotoxicity determined by LVEF?
A reduction in LVEF by >10 absolute percentage points to a value <50%, or to ≥50% with a concurrent GLS drop >15% (BSE/BCOS, 2021).
How often should EchoCG be performed during anthracycline/trastuzumab therapy?
By default every 3 months, with a personalized approach to serial assessment (BSE/BCOS, 2021).
When should a patient be referred to a cardio-oncology service?
All with confirmed cardiotoxicity; with GLS reduction >15% against a background of normal LVEF, referral for expert evaluation can be considered (BSE/BCOS, 2021).
How reliable is LV function assessment in atrial fibrillation?
In AF, due to variability in cardiac cycle duration, systolic and diastolic function indicators may have limited reliability (BSE/BCOS, 2021).