“Is a angioplasty better than a bypass for treating heart blockages?”

No angioplasty is not better in this scenario.

The surgeon must have a reason to suggest bypass surgery.

This is a very complex and very loaded question. I general, surgery is better over time for multilevel disease. That means the long term outcomes are better over time. However there are many lesions that are very suitable to stenting and today endovascular treatment is the first line treatment all over the world. To be able to answer such a question one has to now about the condition and calibre of the distal outflow vessels. Diabetics often have poor quality vessels and often stenting is an only option. If it is a left mainstem lesion surgery is better. If there are good collaterals stenting may be the first choice. The answer is that a good Cardiologist will be able to not only diagnose the exact problem but to also suggest the best treatment for the particular problem. My conviction is that the more lesions there are the more stents will be needed and hence surgery becomes more appropriate

Cardiac stents are usually offered before heart surgery with bypasses. If the heart surgeon suggested surgical bypass then there is a reason that the stents were not an option.

Bypass surgery is much better with a higher survival rate and greater freedom from repeat episodes of ischemia (decreased oxygen delivery). Despite a slightly higher risk of slow wound healing, bypass surgery is the best option for diabetics with coronary artery disease.

I will have to agree with your Fathers doctor if it is like you say. There are some things you have to do what you can and hope and pray for the best.

Angioplasties are usually the best option for one or two blockages but usually not a good choice for multi-vessel disease.