Echocardiography image quality of global longitudinal strain in cardio-oncology: a prospective real-world investigation

Background Left-ventricular (LV) global longitudinal strain (GLS) has been reported to be a robust and sensitive marker of chemotherapy-induced cardiac damage. Image quality is paramount for accurate GLS measurements. In real-world cardio-oncology settings, the incidence of suboptimal echocardiography quality and its significance in clinical decision-making have not been well investigated. This prospective study examined the incidence and impact of suboptimal echocardiographic image quality on detecting subtle myocardial damage by chemotherapy. Methods Seventy-seven consecutive patients with breast cancer (age, 52 ± 12 years, 76 women, 33 with left-sided breast cancer) were included in this study. Echocardiography was performed at 3-month intervals 1 year before and after chemotherapy initiation. We classified the image quality of each echocardiographic acquisition into three groups: optimal, suboptimal, or inadequate for speckle tracking. Results Among the 376 examinations obtained during the cardiac monitoring, the image quality in 194 (52%) was optimal, suboptimal in 159 (42%), and inadequate in 23 (6%). The interobserver reproducibility was 0.91 in the optimal and 0.21 in the suboptimal group. In contrast, the optimal group showed progressive impairment in both GLS ( p = 0.001) and LV ejection fraction (LVEF) ( p < 0.001) during follow-up, and the suboptimal group showed a progressive decrease in LVEF ( p = 0.006), but not in GLS ( p = 0.13). Left-sided mammotomy and/or reconstruction surgery and high body mass index were significant determinants of suboptimal image quality. Conclusions Even in cases of minor image quality impairment, the physician should assess GLS carefully to avoid errors in crucial clinical decision-making.