I'm a retired physician. Do you think the OP meant Electrocardiogram? I ask this because Echocardiograms can't diagnose blocked arteries. AN ECG/EKG/Electrocardiogram can give some idea of the blocked arteries location, if that's what this OP has. An echocardiogram is going to look at the heart valves and if there is any problems with the blood's flow through the chambers of the heart, NOT the blood flow to the heart muscle itself. He would need a CT angiogram for that.
If it was an echocardiogram and they thought he needed emergent hospitalization, the only COMMON things I can think of for this is if it showed an ascending thoracic aneurysm, or acute or severe chronic heart failure.