Via Star Tribune
“As you read these words, your heart’s left ventricle is pumping out as much blood as it can. Hopefully it’s enough.
If your heart is working normally, its left ventricle is pushing out 55 to 70 percent of its total blood volume with each beat. If this “ejection fraction” falls below 40 percent, you may have at least mild heart failure and may feel winded walking up stairs. But cardiologists have long sought a quick and inexpensive way to detect people whose heart is performing between those ranges and can be treated before their condition worsens.”