My father (62 year old, smoker) was diagnosed with a single mid LAD 100% occlusion. Cardiologist tried for Angioplasty but failed as the block is too hard and long, doctor suggested to go for CABG. My father is free of any symptoms except for a little breathlessness when walking/climbing stairs after taking food (could be attributed to smoking also).
We have taken multiple opinions from various cardiologists/CT surgeons in hyderabad and surprisingly got mixed response.
Some say medical management/life style changes is enough for now as the block is in the middle and there are collaterals (50-60%).
but some say there is a chance of heart muscle damage in stressful situations, and if any future blocks in other major arteries may prove fatal, so bypass is the best option and it will improve the lifestyle.
We are facing a difficult situation whether to go for bypass or not and appreciate your help in this regard.
Lifestyle changes:-
Your Father can immediately make huge improvements to his health by giving up smoking. This will increase his oxygen delivery and likely stop the shortness of breath on the stairs. This will be the main cause for his disease and will very likely cause more blockages.
Collaterals:-
It is very obvious your Father has developed Collaterals because his LAD is 100% blocked. If there were no Collaterals he would be in serious trouble now. A large area of the left ventricle would have died and the output of his heart would have been dramatically lowered, that is if he survived at all. The question is, has he opened enough collaterals. I would say no because of the shortness of breath. He has enough to keep the heart healthy at rest, but not on exertion. However, giving up smoking will increase his concentration of oxygen in the blood and really help with symptoms. Is heart muscle being damaged during exertion? well I would say that it is likely but at the moment this will not be severe enough to kill the cells.
When considering options you need to take something important into account. The Collaterals are being fed from somewhere, and if this supply becomes blocked, then his heart will be in a critical situation.
Options:-
He could immediately stop smoking and have no intervention, apart from medication such as beta blockers. Ensure blood pressure remains in normal limits. He could then continue in his daily life and see how long the current situation holds out. If his symptoms get worse, then you know it is time to go for another option.
The other option is bypass, but he will still have to give up smoking or the bypass grafts will very likely not last long and it will all be for nothing. If they use the internal mammary arteries from the chest for the bypass, it will last many years, probably the rest of his natural life.
I hope you can see the seriousness of his smoking and I cannot emphasise enough how this needs to stop, especially as he now has artery disease. This is the first action and must be taken no matter what else is decided. Every single cigarette will cause further damage to his arteries and this may not be noticeable at first because it's on such a tiny scale, but it will soon become apparent.
I hope this helps.