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However, it is not the old, larger plaques that put you most at risk for heart attacks. The most recent scientific evidence indicates that most heart attacks occur when younger and smaller fatty plaques rupture their outer lining, or cap, and bleed into the coronary artery.
As the plaque is formed, a fibrous cap develops at its roof, which is covered by a single layer of endothelium about as thick as a cobweb. For a while, thus protected, plaques lie quietly in place, doing little perceptible harm to the arteryâ€™s owner. But an insidious process is nonetheless under way. The white blood cells that raced to the rescue, now engorged with oxidized LDL cholesterol, are called â€śfoam cells,â€ť and begin to manufacture chemical substances that erode the cap of the plaque. The cap weakens to the thickness of a cobweb. And eventually, the shearing force of blood flowing over the weakened cap may cause it to rupture.
This is catastrophic. Plaque content or pus now oozes into the flowing bloodstream, and that constitutes a thrombogenic event: nature wants to heal the rupture, and so platelets are activated. They try mightily to stop the invading garbage by clotting the rupture. Thus begins a lethal cascade. The clot is self-propagating, and within minutes, the entire artery may become blocked.
With no more blood flowing through the blocked artery, the heart muscle that was nourished by it begins to die. This is the definition of myocardial infarction, or heart attack. If the person survives this attack, the dead portion of heart muscle scars. Multiple heart attacks and widespread scarring weaken the heart, sometimes causing it to fail. That condition is known as congestive heart failure. If the heart attack is extensive, if it results in an abnormal rhythmical contraction, or if the congestive heart failure is prolonged, the person may die.
If the same process of plaque formation occurs in a noncoronary artery, it can be just as dangerous. Whatever tissue the artery supplies-it could be the leg muscles or even the brainâ€”will not receive its full measure of blood. Whatâ€™s more, a piece of a plaque or a clot can break loose and be carried through the bloodstream, ultimately obstructing an artery far from its source.
Dr. Esselstyn's Kindle edition of "Prevent and Reverse Heart Disease".
University of Maryland School of Medicine in Baltimore, has conducted some astonishing studies that demonstrate, among other things, what a toxic effect a single meal can have on the endothelium.6 Dr. Vogel used ultrasound to measure the diameters of the brachial arteries of a group of students. Then he inflated blood pressure cuffs on the studentsâ€™ arms, stopping blood flow to their forearms for five minutes. After deflating the cuffs, he used the ultrasound to see how fast the arteries sprang back to their normal condition.
One group of students then ate a fast-food breakfast that contained 900
calories and 50 grams of fat. A second group ate 900-calorie breakfasts containing no fat at all. After they ate, Dr. Vogel again constricted their brachial arteries for five minutes and watched to see the result. It was dramatic. Among those who consumed no fat, there was simply no problem: their arteries bounced back to normal just as they had in the prebreakfast test. But the arteries of those who had eaten the fat-laden fast food took far longer to respond.
Why? The answer lies in the effect of fat on the endotheliumâ€™s ability to produce nitric oxide. Dr. Vogel closely monitored endothelial function of subjects and found that two hours after eating a fatty meal there was a significant drop. It took nearly six hours, in fact, for endothelial function to get back to normal.
Patty, I said no to stents until I coded. Dr. Esselstyn says sometimes stents are absolutely life saving. Was that my case? I don't know. I do know that there is some question (which hasn't yet been studied but is passed around among those on some internet groups) that stopping Plavix (which is absolutely necessary after a drug eluting stent) can cause a rebound effect and provoke heart attack or stroke. Evidently stopping Plavix often causes immediate restenosis. So I happen to be damned if I do and damned if I don't.