Abstract 11793: Early Detection of Chemo-cardiotoxicity Assessed by Layer Specific Strain: Myocardial Layer is Most Vulnerable to Anthracycline Chemotherapy

Abstract

Background: Anthracycline-based chemotherapy has a progressive dose-dependent toxicity to the myocardium and is related to a poor prognosis. Early detection of subclinical myocardial dysfunction caused by the chemo-cardiotoxicity is thus important for predicting apparent left ventricular (LV) dysfunction and heart failure. Recently, detailed layer-specific analysis of myocardial deformation has been described. This study assessed LV myocardial dysfunction using layer-specific strain in patients who received anthracycline-based chemotherapy. Methods: Consecutive 54 patients (50 ± 14 years old, all women) with preserved LV ejection fraction (≥50%) after receiving anthracycline chemotherapy were included. Two-dimensional speckle tracking was used to assess circumferential strains (CS) from the three acquired parasternal short-axis views at basal, midventricular, and apical level. Peak systolic CS was determined for the total wall thickness (CStotal) and for each of three myocardial layers (CSendo, CSmyo and CSepi for endocardial, mid-myocardial, and epicardial layer, respectively) using EchoPAC PC software. Twenty normal controls were studied for comparisons. Results: CStotal was worse in patients than in controls (-24.5 ± 7.0% vs -22.0 ± 5.8%, P =0.03) even though LV ejection fraction was not different (P = 0.25). Layer-specific strains showed a decreasing gradient from the endocardium to the epicardium both in controls and patients (P <0.001) and it was more apparent from the endocardium to the myocardium in patients than in controls. CS were significantly different between controls and patients in myocardial and epicardial layers (CSmyo, -23.2 ± 8.0% vs -20.8 ± 7.9%, P =0.01; CSepi, -17.8 ± 6.0% vs -16.0 ± 6.8%, P =0.04), but not significant in endocardial layer (CSendo, -29.4 ± 8.4% vs -28.2 ± 9.2%, P =0.09). CStotal was most related to CSmyo (r = 0.943, P <0.001) and CSmyo correlated with the cumulative doxorubicin dose (r = 0.296, P = 0.03). Conclusion: CStotal was reduced and CSmyo was most impaired in patients, which means that myocardial layer is most vulnerable to anthracycline chemotherapy. Layer-specific evaluation of LV may be helpful for early detection of subclinical myocardial dysfunction in these patients.