The apparent discrepancy between global longitudinal strain (GLS) and ejection fraction (EF) is explained by EF being related predominantly to left ventricular (LV) circumferential shortening, whereas GLS measures longitudinal shortening. Since myofibres that account for longitudinal shortening are located mainly in the vulnerable subendocardium, reduction in GLS may precede reduction in LVEF. Furthermore, with concentric hypertrophy, which is common in HFpEF patients, there is typically a small LV cavity and therefore normal or supernormal EF even when stroke volume is reduced. A limitation of GLS, as well as of EF, is the marked afterload dependency. Additionally, reduced GLS is found in only ∼50% of HFpEF cases. Therefore, in a large fraction of HFpEF patients, GLS will not provide the information needed.
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Heart failure and systolic function: time to leave diagnostics based on ejection fraction?
Published:
17 January 2021