What does it mean if a heart tremor was found on your echocardiogram?

Maybe a murmur? Not sure what a tremor is on echo. I suspect they told you you had a murmur. A murmur is a vibration in the heart which may be due to a leaky heart valve, or a narrowed heart valve. This may or may not ever need to be surgically repaired, but most commonly will need to be reassessed in the future, earlier if you develop symptoms.
Not sure. A heart tremor is not a medical diagnosis. Can you be more specific.