In the uk, blockages under 70% are rarely stented, unless the patients symptoms are extreme. When someone tells you there's a 60% blockage this does sound like a huge restriction but in reality it isn't. Arteries always supply more blood than is required, so there's a huge reserve there. Even at 70% there isn't really a flow problem but then the risk of a full closure developing becomes more apparent so stenting usually gets offered.
An initial management strategy in patients with stable coronary artery disease, PCI (stent procedure) did not reduce the risk of death, myocardial infarction, or other major cardiovascular events when added to optimal medical therapy. (ClinicalTrials.gov number, NCT00007657.
BY RON WINSLOW, Wall Street Journal
"Few innovations have transformed medicine more rapidly than the popular heart device known as a stent. In just over a decade, cardiologists have implanted the tiny metal scaffolds more than 20 million times to prop open diseased arteries.
Now a series of studies suggests aggressive ************** would serve many patients just as well as stents, if not better, while saving billions of dollars in health costs. Just last month, a paper in the Journal of the American College of Cardiology reported that drugs were as effective as stents in improving blood flow through the coronary arteries in patients who have stable angina (chest pain with exertion, no pain with a resting interval) ..."
The American Academy of Cardiology has established guidelines to follow. If the occlusion is less than 70%, no intervention (stent or bypass) and assuming the angina if any is stable (angina with exertion, no pain with rest). If occlusion greater than 70%, intervention if pain cannot be management with medication.
I had a stent implant 6 years ago for a 98% blocked RCA. The circumflex is 72% occluded and the LAD is totally blocked ( a grown vascular suystem to compensate provides a natural bypass). For 6 years medication has successfully treated Coronary heart disease and there doesn't appear to be any progession.
If your father's doctor is an interventional cardiologist, you may get a biased opinion regarding treatment (stents) as a opposed to doctor who is non-interventional. My first cardio doc was interventional and my current doctor for the last 5 1/2 years is non-interventional.
The question you should ask your doctor if medication to treat symptoms is appropriate and if not, why not? Hope this helps.