what is the difference in a 1st degree heart blockage and 3rd degree heart blockage?

Answer 1

Ist degree block=PR is greater than .20
Alot of people have this, and have no other problems. It just means the impulse through the atrium is slowed. It usually doesn't cause any symptoms. Can be there without people knowing it. Can happen from medications.
3rd degree block=the atrial beat doesn't coincide with the ventricular beat; they both are beating independantly of each other. This is a serious condtion. Usually requires a pacemaker, unless the patient is stable, and a definite reason can be discovered, with a definite cure. The only time I've seen this reversed is by stopping certain medication. It can occur with heart diesease, heart attack. In some cases it can be temporary, and revere itself, like with a heart attack, medication problems, or other serious condtion.

Answer 2

I wonder if you mean first degree heart block, rather than blockage. heart block is a rythym dysfunction, blockage refers to the arteries being clogged and those are usually discussed in percentages rather than degrees.
http://en.wikipedia.org/wiki/First_degree_heart_block
this site gives some good information on heart block.

Answer 3

a third degree heart block is the worst, a complete heart block,no signals can travel through the av node. in a first degree the signals are slowed down a little.