Description

how is stroke volume calculated ?

**How is Stroke Volume Calculated?**

When it comes to understanding the workings of the heart, one of the key metrics used to assess cardiac function is stroke volume (SV). So, how is stroke volume calculated?

Stroke volume is defined as the volume of blood pumped out of the heart’s left ventricle during each systolic cardiac contraction. According to physiology, it is calculated as the difference between the end-diastolic volume (EDV) and the end-systolic volume (ESV).

There are various methods used to calculate SV, including Doppler echocardiography, magnetic resonance imaging (MRI), and computed tomography (CT) scans. However, the most common method is the non-invasive Doppler echocardiography.

By measuring the Doppler flow in the aortic valve, the SV can be calculated. The formula used is as follows:

SV = VTI x CSA

Where VTI is the velocity-time integral, CSA is the cross-sectional area of the aortic valve, and SV is the stroke volume.

In addition to Doppler echocardiography, other methods used to calculate SV include cardiac output, hemodynamic monitoring, and the Frank-Starling mechanism.

Cardiac output (CO) is calculated as the product of SV and heart rate (HR):

CO = SV x HR

According to physiology, the average SV of a 70 kg male is 70 mL. However, it’s essential to note that not all the blood that fills the heart by the end of diastole can be ejected from the heart during systole.

In conclusion, stroke volume is a crucial metric used to assess cardiac function, and it is calculated using various methods, including Doppler echocardiography, cardiac output, and hemodynamic monitoring.

For more information and to learn how to calculate stroke volume, please check the links below:

* [https://www.ncbi.nlm.nih.gov/books/NBK547686](https://www.ncbi.nlm.nih.gov/books/NBK547686)
* [https://easytocalculate.com/how-to-calculate-stroke-volume](https://easytocalculate.com/how-to-calculate-stroke-volume)
* [https://www.thecalculator.co/health/Stroke-Volume-Calculator-997.html](https://www.thecalculator.co/health/Stroke-Volume-Calculator-997.html)

**Useful Links:**

* [https://www.ncbi.nlm.nih.gov/books/NBK547686](https://www.ncbi.nlm.nih.gov/books/NBK547686)
* [https://easytocalculate.com/how-to-calculate-stroke-volume](https://easytocalculate.com/how-to-calculate-stroke-volume)
* [https://www.thecalculator.co/health/Stroke-Volume-Calculator-997.html](https://www.thecalculator.co/health/Stroke-Volume-Calculator-997.html)
* [https://en.wikipedia.org/wiki/Stroke_volume](https://en.wikipedia.org/wiki/Stroke_volume)
* [https://www.omnicalculator.com/health/stroke-volume](https://www.omnicalculator.com/health/stroke-volume)
* [https://www.mdapp.co/stroke-volume-calculator-267](https://www.mdapp.co/stroke-volume-calculator-267)
* [https://ecgwaves.com/topic/stroke-volume-vti-velocity-time-integral-cardiac-output](https://ecgwaves.com/topic/stroke-volume-vti-velocity-time-integral-cardiac-output)
* [https://www.osmosis.org/learn/Stroke_volume,_ejection_fraction,_and_cardiac_output](https://www.osmosis.org/learn/Stroke_volume,_ejection_fraction,_and_cardiac_output)
* [https://www.statpearls.com/point-of-care/29559](https://www.statpearls.com/point-of-care/29559)
* [https://www.iu.pressbooks.pub/humanphys/chapter/stroke-volume](https://www.iu.pressbooks.pub/humanphys/chapter/stroke-volume)

**References:**

* [1] Physiology, Stroke Volume – StatPearls – NCBI Bookshelf
* [2] How To Calculate Stroke Volume – Easy to Calculate