Left ventricular Stroke Work Index (LVSWI)

The left ventricular stroke work index (LVSWI) is a beat-by-beat assessment of myocardial systolic and diastolic function that integrates systemic hemodynamics to produce a comprehensive measure of cardiac performance [2, 3]. The LVSWI can be calculated using Doppler echocardiography (ECHO-LVSWI) based on the stroke volume index (SVI) and ratio of mitral valve E velocity to medial mitral annulus e’ velocity (E/e’ ratio, used to estimate left ventricular filling pressures), and has been found to be strongly associated with mortality in CICU patients [2, 3].

LVSWI strongly and inversely associated with the risk of in-hospital mortality in CICU patients across the spectrum of cardiogenic shock severity, providing justification for its routine measurement.

A lower LVSWI identifies high-risk patients in the group without overt shock, while a higher LVSWI identified patients with hemodynamic instability or hypoperfusion who is at lower risk of adverse outcomes.

LVSWI =SI*MAP*0.0144

LVSWI = Ventricular Stroke Work Index, Left (g*m/m2)

SI = Stroke Index (mL/beat/m2)

MAP = Mean Arterial Pressure (mmHg)

*0.0144 is a conversion term to equalize units.

Also: LVSWI = SI * (MAP - PAOP) * 0.0136; and

LVSWI = (CI/HR) * MAP * 0.0144

CI = Cardiac Index (mL/min/m2)

HR = Heart Rate (bpm)

1.       https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8906587/

2.      Jentzer JC, Anavekar NS, Burstein BJ, Borlaug BA and Oh JK. Noninvasive Echocardiographic Left Ventricular Stroke Work Index Predicts Mortality in Cardiac Intensive Care Unit Patients. Circ Cardiovasc Imaging. 2020;13:e011642. doi: 10.1161/CIRCIMAGING.120.011642 [PubMed] [CrossRef] [Google Scholar]

3.     Choi JO, Lee SC, Choi SH, Kim SM, Choi JH, Park JR, et al. Noninvasive assessment of left ventricular stroke work index in patients with severe mitral regurgitation: correlation with invasive measurement and exercise capacity. Echocardiography. 2010;27:1161–9. doi: 10.1111/j.1540-8175.2010.01222.x [PubMed] [CrossRef] [Google Scholar]

4.       https://www.scymed.com/en/smnxph/phmhy179.htm

5.       https://www.scymed.com/en/smnxph/phdhd125.htm

6.       https://www.scymed.com/en/smnxph/phgdc016.htm