Fractional Area Change (FAC)
Calculate
cm²
cm²
FAC:
| FAC | Ejection Fraction |
| 60% | 75% |
| 50% | 66% |
| 40% | 54% |
| 30% | 42% |
| 20% | 29% |
| 10% | 15% |
60%FAC
40% FAC
20% FACHow to calculate Fractional Area Change (FAC).
- Measure the LV End-Diastolic Area (EDA) and End-Systolic Area (ESA). The optimal view is the LVSA view from the mid Transgastric acoustic window. The left ventricular area should be traced in end-diastole and end-systole. The difference of the two, divided by the left ventricular end-diastolic area is the fractional area change. Note that the fractional area change is NOT the ejection fraction. Ejection fraction is based upon (extrapolated) volumes whereas the FAC is based upon area. Therefore, values of FAC will be less than the ejection fraction. See below for a comparison.