The human heart has natural bypasses built in. In many patients, if an artery becomes blocked, tiny vessels will open up to bypass this. These vessels (collaterals) are something we are born with and work with the majority of people, but not everybody. The collaterals will either bridge a blockage, passing a flow of blood around the blockage from one side to the other, or, they will give a feed across from another healthier coronary artery nearby.
The collaterals differ with the source feed usually depending if you are left dominant, right dominant or co-dominant. This is just how the coronary arteries are mapped and differ in length and which one feeds the posterior descending at the back.
I just re-read your post and maybe you are asking how the cabg works?
It is simply taking an artery or vein from another area of the body, connecting it to an area below the blockage, and the other end to an artery which has a good blood flow. Sometimes they connect one end to the upper part of the artery with the blockage, then the lower end to below the blockage.
It's easier to imagine a long metal pipe with a blockage in the middle, so no water can get through. A plumber connects a pipe from one side of the blockage to the other so the water can go around the blockage.
Well thank you for your kind response. Actually it is seen from angiography that LAD had 100 % blockage but doctor said that other vein from RAD is supplying blood to LAD till the end of block.
My querry is that
1. What is level of risk involved in this case for heart attack
2. How dangerous is this and it is normal case occuring in other patinets too.
3. Is this bypass suplly of blood is since birth ot developed over period of time at young age (His age is 68yrs)
4. Whether this block is by birth or developed over period of time as he don't have any complaint of angina or heart
Kindly address my above queries
The collaterals are vessels we are born with and are used when necessary. It is not dangerous for a person to be using collaterals, it is more dangerous if they do not open. I had a solid blockage in my LAD for years, and was told that because it was large and heavily calcified, there was virtually no risk of it rupturing, causing a heart attack.
The key thing here is not the blockage, but the supply for the LAD from the right side. Just make sure this vessel is clear so it can supply the LAD and the right side. If blood flow in this vessel drops due to disease, both sides of the heart will be compramised.
Thax for your kind information. Is there anything to do with either angiograpphy or bypass because our doctor suggested that. It advisable to treat this?
I'm not sure what you are asking? You say your Father already had a bypass? which is supplying blood to the bottom of the LAD (standard procedure) and the LAD has a blockage of 100%. Is this a new blockage which has formed?