Role of global longitudinal strain to identify and monitor left ventricular dysfunction over time in Becker muscular dystrophy

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Myocardial involvement is a frequent manifestation of Becker muscular dystrophy (BMD) representing one of the main causes of death; however, it has been shown that left ventricular (LV) systolic function is not specifically related to the degree of skeletal myopathy and therefore each patient should be screened for myocardial involvement. Advanced echocardiographic measures of LV function, such as global longitudinal strain (GLS), have not been studied in BMD patients and might help in identifying myocardial involvement at an early stage. Aim of this study was therefore to perform a longitudinal assessment of LV function but using LV ejection fraction (EF) and GLS in a relatively large cohort of BMD patients (Fig 1). Methods: A total of 40 BMD patients (39 ± 13 years) were analyzed including standard and advanced echocardiography at the time of their first visit and at 24 months (IQR 23-25) follow-up. A control group consisted of 22 age- and gender-matched healthy subjects. Results: BMD patients showed significantly impaired LV systolic function as compared to controls both by LVEF (47 ± 11% vs. 61 ± 8%, p < 0.001) and LV GLS (-16% (-17%-12%) vs. -19% (-21%-18%), p < 0.001). However, a total of 32 (80%) BMD patients showed impaired LV GLS (based on a reference value -18%) and only 24 (60%) BMD patients showed reduced LVEF (based on reference value 52%) suggesting at the important role of LV GLS to identify early myocardial involvement. Furthermore at the follow-up assessment (available in n = 29 patients), LV GLS showed significant deterioration in BMD patients (from -15%±3 to -14%±4, p = 0.004), while LVEF and LV volumes did not show significant changes over time. Conclusion: LV GLS is significantly impaired in BMD patients and shows progressive deterioration over time, while LVEF remains unchanged. LV GLS might therefore represents a new tool to improve identification of early myocardial involvement and subclinical changes in these patients. Abstract Figure. LV systolic function in Becker disease