80% stenosis can give symptoms.
If it can not be managed by medications, bypass surgery or placement of a stent can solve the problem.
Stenting is the quick solution but at the ramus/LAD origin stenting is often difficult.
I can understand the cardiologist's suggestion for treating with medication.
80% stenosis is normally not a critical situation and often manageable with medication. So if your husband has no chest discomfort, that seems the treatment of choice.
Did the doctor indicate that the symptoms (feeling very weak, giddiness and/or vomiting) were related to the stenosis?
I still find it hard to believe that the stenosis is the cause for those symptoms.
Are there still tests running to find other causes for them?