Stroke Work is defined as which of the following?

Stroke Work is defined as which of the following?

• A. SV × MAP
• B. (MAP - VEDP) × SV × 0.0136; normally 60-80 gm·m/beat
• C. (CO × MAP) / 100
• D. (SBP - DBP) × SV

Answer: (B)

Stroke work is the external energy the ventricle must deliver with each beat to eject blood against the arterial system. It equals the pressure the ventricle must overcome (the afterload) times the amount of blood ejected (the stroke volume). The most practical way to estimate this is using the difference between mean arterial pressure and the left ventricular end-diastolic pressure, multiplied by the stroke volume, and then converted to standard work units. So (MAP − VEDP) × SV × 0.0136 gives the work per beat in gram-meters, with typical values around 60–80 g·m/beat. The factor 0.0136 converts mmHg·mL to g·m, aligning the units. This reflects how higher afterload or larger stroke volume increase work, while a higher LVEDP reduces the net pressure gradient the ventricle must generate.

Stroke work is the external energy the ventricle must deliver with each beat to eject blood against the arterial system. It equals the pressure the ventricle must overcome (the afterload) times the amount of blood ejected (the stroke volume). The most practical way to estimate this is using the difference between mean arterial pressure and the left ventricular end-diastolic pressure, multiplied by the stroke volume, and then converted to standard work units. So (MAP − VEDP) × SV × 0.0136 gives the work per beat in gram-meters, with typical values around 60–80 g·m/beat. The factor 0.0136 converts mmHg·mL to g·m, aligning the units. This reflects how higher afterload or larger stroke volume increase work, while a higher LVEDP reduces the net pressure gradient the ventricle must generate.