Aclient has been having cardiac symptoms for several months and is seeing a cardiologist for diagnostics to determine the cause. how will the client's ejection fraction be measured?

Ejection fraction will be measured by echocardiography.

Ejection fraction is the percent of blood pumped by the heart. An ejection fraction 70% means that from 100% of blood inside the ventricle, 70% will be sent out and 30% will still be found in the heart. 
Echocardiography can be used to measure the ejection fraction of the heart and it was less invasive than other methods.

The heart's ejection fraction is measured using an echocardiogram or multiple gated acquisition scan.