Myocardial Work: Methodology and Clinical Applications

Abstract

A precise and accurate assessment of left ventricular (LV) contractility is of utmost importance in terms of prognosis in most cardiac pathologies. Given the limitations of ejection fraction (EF) and global longitudinal strain (GLS) due to their load dependency, a novel imaging tool called myocardial work (MW) has emerged as a promising method for LV performance evaluation. MW is a novel, less load-dependent method based on computation of myocardial strain–arterial blood pressure curves. This method provides a more detailed assessment of segmental and global LV function incorporating the patient’s LV pressure and is derived by brachial artery pressure utilizing an empiric reference curve adjusted to the duration of the isovolumic and ejection phases as determined by echocardiography. The clinical implications of this unique method have been expanding in the last few years, which attest to the robust additive role of MW in routine practice.

Subclinical Myocardial Dysfunction in Patients with Persistent Dyspnea One Year after COVID-19

“…However, LV myocardial performance assessed using MW was independently associated with persistent dyspnea. MW has recently emerged as a promising technique which can provide a more precise evaluation of the LV function by incorporating the LV pressure-strain relationship [ 29 , 30 ]. Similarly, in a retrospective study on hospitalized COVID-19 patients, a decrease in MW efficiency was associated with inflammation burden and in-hospital mortality [ 41 ].…”

“…The applicability of MW in various cardiac pathologies has been suggested by several recent publications due to its lower load-dependency and hence higher sensitivity in detecting subclinical dysfunction than LVEF and GLS alone [ 29 , 31 , 43 ].…”

“…MW was obtained from the pressure-strain loop area constructed from the LV pressure curves and GLS, as recommended by current guidelines [ 29 , 30 , 31 ]. The MW parameters acquired using GE Healthcare, Vingmed Ultrasound, Horten, Norway, EchoPAC software, version 20.3, were global work index (GWI), global work efficiency (GWE), global wasted work (GWW), and global constructive work (GCW).…”

Impact of Brachial-Ankle Pulse Wave Velocity on Myocardial Work by Non-invasive Left Ventricular Pressure-Strain in Non-hypertensive and Hypertensive Patients With Preserved Left Ventricular Ejection Fraction

“…Constructive work was defined as work during shortening in systole and lengthening in isovolumetric relaxation; conversely, wasted work was the work performed during lengthening in systole and shortening in isovolumetric relaxation; and constructive work divided by the sum of constructive and wasted work served as work efficiency. The methodology above mentioned was validated in previous publications (4). On the basis of previous studies, abnormal MV was defined as GWI ≥ 2,200 mmHg%, GWE ≤ 97%, GCW ≥ 2,500 mmHg% and GWW ≥ 90 mmHg% (19)(20)(21).…”

Do diurnal changes in blood pressure affect myocardial work indices?

“…MW has been shown to be a more sensitive marker of systolic dysfunction than LVEF and GLS in patients with heart failure, coronary artery disease, valvular heart disease, hypertensive heart disease, cardiac dyssynchrony, hypertrophic cardiomyopathy and amyloidosis. 11 The incremental value of MW as a prognostic marker for survival and hospitalizations has been also reported, especially in patients with chronic heart failure. 12 …”