Myocardial Work in Septic Shock Patients: an Observational Study

Myocardial strain analysis has emerged in the last decade as a reliable tool for studying myocardial mechanics, adding information on cardiac performance when compared with traditional parameters of left ventricle (LV) systolic function, such as ejection fraction (EF).

However, their relative load dependency makes the myocardial deformation indices unable to account for changes in pre- and afterload.

Myocardial work (MW) is emerging as an alternative tool for studying LV myocardial systolic function, because it incorporates both deformation and load into its analysis. In this context, MW could be considered as an advancement of myocardial strain, allowing to investigate LV performance also in cases of changes in afterload that could lead to misleading conclusions if relying only on strain analysis.

Conditions of increased afterload can in fact negatively impact on myocardial strain even if MWis normal. MW assessment was initially calculated using invasive pressure measurements, which limited its widespread use in clinical practice.

Recently, Russell et al. demonstrated that pressure-strain loops (PSLs) could estimate LV performance in a non-invasive manner, deriving LV pressure (LVP) curves from non-invasively acquired brachial artery cuff pressure. To date, the technique has been applied in myocardial ischaemia and in identification of cardiac resynchronization therapy (CRT)-responders with good results.