Atherosclerosis is the thick cholesterol laden plaque that builds up on the inside of our arteries when we eat the typical Australian diet. Arteries do not simply gradually block up like a rusting water pipe. Heart attacks are most often the result of a sudden blockage in an artery that is only partially blocked with plaque. A whole foods plant based diet rapidly reduces the risk of heart attack.
The current paradigm of heart disease* views arteries as if they were water pipes. Factors such as high cholesterol, diabetes and smoking causes a gradual build-up of cholesterol on the inside of the artery like scale in a pipe. Eventually the pipe becomes blocked and blood supply is interrupted.
*There are many diseases that can affect the heart muscle and the heart valves. In this discussion we are using the term “heart disease” to refer to the diseases caused by narrowing or obstruction of the coronary arteries that supply the heart muscle. There are various terms that are used to label this type of heart disease: coronary artery disease (CAD), coronary heart disease (CHD), ischaemic heart disease (IHD), and myocardial ischemia. The processes which occur in the arteries of the heart can and do occur elsewhere in the body.
Atherosclerosis is the end result of the complex process that leads to the accumulation of cholesterol and scar tissue within the artery wall. It is an insidious process that produces few if any symptoms until it is advanced enough to slow or block the flow of blood. In the early stages, fatty streaks develop inside the arteries as cholesterol builds up in the lining of the artery. The primary cause is the unnaturally high levels of LDL cholesterol associated with a diet rich in meat, dairy and processed foods and deficient in whole plant foods. The cholesterol deposited within the artery wall triggers an inflammatory response in which white blood cells invade the diseased artery wall, ingest the cholesterol and release further inflammatory chemicals. Eventually the interior of the artery becomes narrowed by a thick layer of cholesterol-laden scar tissue – this is atherosclerosis.
Arteries are not just water pipes and atherosclerosis has more consequences than just progressively reducing blood flow. The large arteries of the body are more like rubber tubes than hard pipes and they stretch with each heart beat and bounce back between beats, giving the smaller vessels a more steady blood flow. Atherosclerosis makes these arteries stiffer (“hardening of the arteries”) so that they no longer absorb the shock wave that each heartbeat produces. The smaller vessels further down the line then get pounded by the water hammer like shock wave of each heartbeat. These smaller vessels then become diseased more quickly resulting in damage the organs such as the brain and kidneys.
The paradigm of heart disease that views arteries as water pipes has an upgrade that describes how heart attacks occur.
The gradual reduction in blood supply by atherosclerosis can cause the heart muscle to become weak and baggy so that it cannot pump effectively. The result is heart failure. Other organs in the body can also become progressively impaired. But heart attacks and most strokes happen when blood supply is suddenly cut off, resulting in death by asphyxiation to the cells downstream from the blockage. Atherosclerosis is an uneven process and forms localised lumps on the inside of arteries are called plaques. These plaques can burst open like a pimple on the inside of the artery. The material in the plaque causes the blood to clot immediately completely blocking the artery and obstructing blood flow to everything downstream. This can happen in arteries that are only partially blocked with plaque. Therefore an exercise ECG stress test can remain normal right up until the moment of the heart attack.
Cholesterol plaques that are actively growing are cauldrons of inflammation, and this inflammation causes the “cap” over the plaque to become thinner, increasing the risk of plaque rupture and heart attack – these are “unstable plaques”. It has been observed that rapidly reducing blood cholesterol stabilises plaques in just a few weeks, far quicker than the length of time it takes for a plaque to regress as demonstrated by angiograms. A plant based diet is much better than cholesterol tablets alone for stabilising plaques as it not only reduces fasting cholesterol, but also deals with the inflammatory storm that follows every fatty meat-based meal.
Heart disease in women may follow a slightly different course to men. It is the same disease process but plaque formation tends to be more diffuse. Diffuse plaque leads to relatively more diffuse heart damage (heart failure) than localised events (heart attacks).
Dr Michael Gregor describes the process of plaque formation and plaque rupture as analogous to pimples in his video Arterial Acne:
“Atherosclerotic plaques in coronary arteries may be more aptly described as pimples, initiated by the infiltration of cholesterol into the lining of our arteries. The ending, should blood flow to our heart muscle be cut off by a clot formed by the rupture of one of these inflamed pockets of pus in our arterial lining, is a heart attack”.
In this 8 minute video, Dr Esselstyn discusses how cholesterol accumulates in the coronary arteries, provoking an inflammatory reaction which can lead to plaque rupture. This is the main cause of heart attacks and mostly occurs in arteries that are not badly enough blocked to be treated with stents or bypasses. Fortunately plaques become more stable after only a few weeks on a whole foods plant based diet.
Caldwell Esselstyn, MD — “No More Heart Attacks — Ever”
Our current paradigm of artery disease, even with the ruptured plaque upgrade, is still too much of a water pipe analogy. Only by giving the endothelium centre stage can we understand how dietary factors cause atherosclerosis, high blood pressure and erectile dysfunction. See Endothelium, also Heart Health – Resources