This is an interesting topic. The ejection fraction is a measurement of left heart function obtained during echocardiography. The question is how does the heart fail when the measured EF is normal?
Heart failure is an important cause of shortness of breath which has to be differentiated from lung causes of shortness of breath. Often the distinction between the two conditions is not obvious clinically without further investigations. Relevant investigations include ECG, NT proBNP (blood test), echocardiography, chest x-ray and coronary angiography.
Heart failure with preserved ejection fraction is a type of heart failure with normal or near normal ejection fraction and objective evidence of diastolic dysfunction.
More than half of heart failure patients have heart failure with a maintained ejection fraction. The illness primarily affects the elderly, accounting for 4.9 percent of the population over the age of 60. It appears to be more common in women, and it is projected to become more widespread as people live longer.
Link to this interesting article which I have read:
Heart failure with preserved ejection fraction | Radiology Reference Article | Radiopaedia.org
Feger, J., Worsley, C. Heart failure with preserved ejection fraction. Reference article, Radiopaedia.org. (accessed on 24 Mar 2022) https://doi.org/10.53347/rID-93980