The 70% blockage is a guideline by the AAC./AHA. Based statistically, it may be the percentage of heart occlusion problems that causes symptoms, but it is an estimate and doesn't represent individual specifically. My doctor is a non-interventioanal cardilogist and treats angina caused by vessel stenosis with medication. I have had an occlusion greater than 70% for years and medication prevents any symptoms.
If medication does not effectively prevent symptoms, then according to guidelines do a stent implant, if unable to stent then bypass. The guideline is more symptom oriented than occlusion size. Medication can open vessels, stent can brace a wider opening and bypass will effectively relieve angina structually. There maybe intevention in the event of an emergency...no choice.
I am feeling the same way. I have a 50% blockage in an artery they say they cannot stent, so in my case I would rather wait and just take the meds and etc. I do not want cabg.
The line has to be drawn somewhere to establish if a procedure carrying risk should be performed or not. 70% was chosen because anything less can be treated (in nearly all cases) with medication. 70% and above does pose more risk of rupture and symptoms not being controlled by medication. I too was amazed at this when told by my cardiologist, but he said nearly all patients with a 60% blockage don't even know it's there. The arteries are much larger than they need to be, giving a huge reserve. For 2 years while cardiologists were trying to decide my fate with surgical options, my left artery had a 3-5% feed. This was all the left side of my heart had to try and function. I was gardening, carrying shopping, walking over a mile every day. All thanks to medication.