Monday, February 11, 2008

Tracking plaque 1950s style

Before EBCT scanners arrived on the scene, this is how you assessed plaque in peripheral arteries. Certainly back in the 1950s this was cutting edge. Coronary arteries are a non starter using this technique!

"With both needles securely in place [one in each femoral artery, no local block, ouch! My comment], 20 c.c. of 35%, Diodrast [an old fashioned type of iodine contrast, very irritant, again my comment] was injected simultaneously into both arteries from 50 c.c. syringes equipped with stopcocks, polyethylene tubing and Luer locks. The injection lasted about 7 seconds and was accompanied by fairly severe but transient pain followed by a burning sensation passing down into the legs and feet and lasting 20 to 30 seconds. This was followed by visible flushing of the skin of the legs in some cases. Meanwhile 5 to 7 x-ray films 14" x 17" (35 x 42.5 cm.) were exposed with a cassette changer at 1.5 second intervals, starting when about 10 c.c. of the dye had been injected."

No one died from reaction to the dye and all of them came back for a repeat arteriogram using the same technique. Some even came back twice!

Assessing the radiographs in the paper is quite difficult. Getting X rays in to journals while trying to maintain diagnostic quality is never easy, even today. When it's a pdf of a scan of a print of an X ray in a journal published in 1954 which you have in front of you, you need the eye of faith to see what the authors saw. However, with it being a three author paper this probably increases the likelihood of plaque regression cited as being real.

Yes, it seems they had plaque regression in 1954. It was a very small series (reading through the technique, I'm not surprised!) and the changes are not particularly convincing when viewed from 53 years later. But they do claim some degree of reversal over about a 3 month period. The radiologist scoring the radiographs for plaque changes was blinded as to treatment vs control when he assessed the arteriograms.

Apart from Professor Yudkin's throw away comment about ascobate and heart failure, I don't think I've seen a lot of information on ascorbate for atherosclerosis in the literature. Obviously the Vitamin C Foundation makes lots of claims nowadays, but I don't think I've seen anything serious in print. Dr Davis has only commented once on the Pauling/Rath therapy (ascorbate/lysine/proline) for IHD, and that was to say it doesn't drop Lp(a). Fair enough, but Lp(a) is another story. Obviously if anyone is eating modest fat, lots of fruit and vegetables and avoiding saturated fat there is no way they will drop their Lp(a), whatever vitamins they take!

The group doing the arteriograms were giving ascorbate at 500mg three times a day as their treatment, without change in diet. This strikes me as a miniscule dose. I just wonder how much ascorbate Prof Yudkin's elderly heart failure patients were taking in the 1970s. Oh, and whether Dr Willis' patients (it's a Canadian study) were getting more sunshine during those two to six months of his study period........ Vitamin D again? The paper was published in December 1954, it all depends on how long it took them to gather and publish their data. A modern day research scientist can get a paper from results to e-pub in about six weeks. Modern clinicians can take >2 years!

But however it is achieved, I don't think it's arguable; atherosclerosis is reversible.


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