Critical Care & Hemodynamics

Left Ventricular Stroke Work Index (LVSWI) Calculator

Calculate indexed LV work per beat using flow, heart rate, and the systemic-to-left-atrial pressure gradient.Need the full picture? Open the combined Swan-Ganz calculator →

Enter measurements

MAP sourceCardiac index source

Cardiac index (CI)

L/min/m²

Heart rate (HR)

beats/min

Mean arterial pressure (MAP)

mmHg

Mean PAWP / PCWP

mmHg

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Calculated result

—g·m/m²/beat

(CI / HR) × (MAP − PAWP) × 13.6

Enter the required measurements to calculate a result.

Educational use only. This tool and its outputs do not constitute medical advice, diagnosis, or treatment and do not replace clinical judgment. Independently verify the inputs, equations, assumptions, units, and outputs, and confirm that the tool is appropriate for your intended use before relying on a result.

What is LV stroke work index (LVSWI)?

LVSWI estimates the pressure–volume work performed by the left ventricle on each beat, indexed to body surface area. It combines stroke volume index with the difference between MAP and mean PAWP.

How is it calculated?

(CI / HR) × (MAP − PAWP) × 13.6

CI is cardiac index in L/min/m²; HR is heart rate in beats/min. MAP and mean PAWP are in mmHg. CI / HR gives L/m²/beat; multiplying by 13.6 converts mmHg·L to g·m. If stroke volume index is entered in mL/m²/beat elsewhere, its corresponding conversion factor is 0.0136.

Result units: g·m/m²/beat.

Clinical interpretation

Lower LVSWI may accompany reduced pump performance and has prognostic associations in advanced HF. A reference below 20 g·m/m²/beat was associated with death or deterioration on a transplant waitlist; that cohort-derived value should not be applied as a universal diagnostic threshold. Heart rate, loading conditions, and support affect the result.

Clinical considerations

Use time-aligned CI, HR, MAP, and mean PAWP. Large V waves or a questionable wedge require waveform review; an end-diastolic wedge is not automatically equivalent to mean PAWP.

If deriving CI from CO and BSA, use a consistent body-size method. LVSWI is not a load-independent measure of contractility.

References

Independently created by MendelMD. These educational calculators are not provided, endorsed, or independently validated by the American Heart Association.