Two-dimensional speckle tracking echocardiography in evaluating radiation-induced heart damage

Area of Science:

• Cardiology
• Oncology
• Radiotherapy

Background:

• Radiation-induced heart damage (RIHD) is a known complication of thoracic radiotherapy.
• However, the cardiac toxicity of stereotactic body radiotherapy (SBRT) has not been extensively studied using advanced imaging techniques like 2D speckle tracking echocardiography (2D STE).

Purpose of the Study:

• To investigate the early cardiac toxicity of thoracic SBRT using 2D STE.
• To assess changes in global longitudinal strain (GLS) and other cardiac parameters following SBRT.
• To evaluate the incidence of major adverse cardiovascular events (MACE) after SBRT.

Main Methods:

• A prospective cohort study involving 48 patients undergoing thoracic SBRT for malignant tumors.
• Echocardiography and 2D STE were performed before and within two months after SBRT.
• Primary outcome was a decrease in GLS ≥ 10%; secondary outcomes included MACE, ECG, and circulating biomarkers.

Main Results:

• 44% of patients showed evidence of RIHD within two months post-SBRT.
• A significant decrease in GLS was observed post-SBRT (P=0.008), while LVEF and other conventional markers remained unchanged.
• Subgroup analysis indicated GLS decline irrespective of anthracycline treatment, with a more pronounced decrease in patients who received anthracyclines.

Conclusions:

• Subclinical cardiac dysfunction is detectable early after SBRT using strain analysis, even when conventional cardiac indices are normal.
• The observed decrease in GLS suggests early cardiac impairment following SBRT.
• These findings highlight the utility of 2D STE in monitoring cardiac health in patients undergoing thoracic SBRT.