Friday, September 22, 2017

  • Cardiovascular Disease

1. Atherosclerosis

  • Facts

  • CVDs are the number 1 cause of death globally: more people die annually from CVDs than from any other cause.

  • An estimated 17.7 million people died from CVDs in 2015, representing 31% of all global deaths. Of these deaths, an estimated 7.4 million were due to coronary heart disease and 6.7 million were due to stroke .
  • Over three quarters of CVD deaths take place in low- and middle-income countries.


  • Out of the 17 million premature deaths (under the age of 70) due to noncommunicable diseases in 2015, 82% are in low- and middle-income countries, and 37% are caused by CVDs.

  • Most cardiovascular diseases can be prevented by addressing behavioural risk factors such as tobacco use, unhealthy diet and obesity, physical inactivity and harmful use of alcohol using population-wide strategies.

  • People with cardiovascular disease or who are at high cardiovascular risk (due to the presence of one or more risk factors such as hypertension, diabetes, hyperlipidaemia or already established disease) need early detection and management using counselling and medicines, as appropriate.


If an airplane crashes hundreds of people die and the news is filled with this top story for days.  Each day in the U.S. approximately 2400 deaths occur from cardiovascular disease alone.  This would be like 6 Boeing 747’s crashing per day!  Yet these deaths generally do not make the news broadcasts unless a famous person dies from a heart attack.  Much effort is put forth to determine the cause of the airline crash—shouldn’t we be as concerned with the cause of cardiovascular disease?



Heart disease usually develops silently—it is known as the silent killer.  Before any damage to the heart occurs a process called atherosclerosis takes place over a period of many years.  This refers to a narrowing of the arteries due to a buildup of fatty material inside the blood vessel walls.  As fat and cholesterol accumulate on the walls, the body reacts by covering the fatty deposits with a tough, fibrous cap (mostly calcium) to prevent a blood clot from forming (if any fatty material is allowed to come into contact with blood, it can stimulate the blood to clot.  The fibrous cap protects against this unwanted clotting.  This capped fatty deposit is known as plaque.

Athero” refers to the “mushy” or “gruel-like” fatty material  and “sclerosis” describes the hard fibrous material of the cap.

This problem can begin as a “fatty streak” in the arteries as early as the teenage years or even younger.  With each decade of life the plaque becomes more prominent. The changes continue until eventually the arteries can become totally blocked. 

Symptoms

There may be no symptoms until the progression is very severe and perhaps no symptoms will ever occur.

If symptoms do arise they may be vague (“atypical”) or they may be classic “angina pectoris,” which is the first symptom in the progression toward a heart attack.  Angina pectoris refers to chest pain on exertion or severe emotional stress that is usually described as heaviness, pressure, or tightness centered in the middle or left side of the chest.  The pain can travel up to the neck or jaw or down either arm.   Occasionally there is also back or stomach area pain.  A large meal or cold weather may also precipitate this pain.

These symptoms are caused by an insufficient blood supply to the heart muscle, referred to as “coronary insufficiency.”  Even under situations of significant exertion a heart artery must have at least 50 to 60 percent of its diameter blocked before the heart muscle suffers from lack of blood supply, which is the cause of the pain.  Many people with narrowing even in the 70 percent range or greater have no recognizable symptoms.
Location of atherosclerosis:  Common sites include the ­coronary arteries, cerebral arteries, carotid arteries, aorta, renal arteries, and femoral arteries. 


Heart Attacks:  Plaques may ulcerate, causing a break in the protective cap.  When this happens, a combination of fibrous and fatty material is released into the blood stream.  Both the liberated fatty material and the ulcerated plaque (sometimes called a lesion) can activate platelets, the body’s clotting cells.  A resulting blood clot or the fatty material itself can lodge in an artery already narrowed by plaque buildup.  If this results in complete obstruction of a coronary artery, the blood flow to the heart muscle itself is stopped and heart muscle tissue will die.  This is known as a myocardial infarction (MI), or heart attack.

Congestive Heart Failure:  Many people die from their first heart attack, but even if they survive, more than 2/3 do not make a complete recovery.  They are left with some form of disability and a permanently decreased quality of life.  Following a heart attack, the heart is weaker because of lost muscle tissue.  When the heart is so damaged that it cannot sufficiently keep the body systems functioning it is referred to as “congestive heart failure.”  In this situation, an affected individual may get short of breath easily, be generally fatigued, experience feet or ankle swelling, or have fluid collect in their lungs. 

Strokes:  Strokes may also result from atherosclerosis.  They are caused by rupture or obstruction (as by a clot) of a blood vessel of the brain  Strokes may cause part of the body to be paralyzed, blindness, loss of speech or hearing, and severe personality or memory problems (depending on which part of the brain is damaged). 

Aneurysms:  The body’s largest artery, the aorta, is commonly affected by atherosclerosis, resulting in aneurysms caused by a weakened lining.  If the aorta bursts death is the almost sure result.  Massive internal bleeding occurs within a few seconds or minutes.

Kidney Damage:  If the renal arteries become affected a person can develop high blood pressure or lose the function of the kidney entirely.

Leg Pain:  Leg pain when walking (“intermittent claudication”), limping, impotence and gangrene can result from atherosclerosis in the femoral arteries in the thigh and posterior tibial arteries in the lower leg and ankle. 

Gangrene:  If the peripheral arteries supplying the legs and arms become narrowed, gangrene can result in blood poisoning and death if amputation is not carried out promptly.


1. Diet

Keep cholesterol levels low.

The higher the cholesterol level the higher the death rate.  A man with a serum cholesterol over 240 mg/dl has more than 3 times the risk of dying from a heart attack than a man with less than 200 mg/dl.  The increase in risk is most pronounced when cholesterol levels climb over the 240 mg/dl mark. 

Study:  Finland—29,000 men and women over a 20-year period (1972 to 1992).  When these individuals lowered the cholesterol in their diets, lowered their blood pressure, and stopped their tobacco use, they reduced their heart attack risk by more than half.

Statistics:  Japan is at the bottom of the scale for heart disease even though their smoking rate is much higher than the U.S.  59 percent of Japanese men and 14 percent of Japanese women smoke while in the U.S. only 28 percent of men and 23 percent of women smoke.  Why is the Japanese rate of heart disease lower than the U.S. rate?  It appears to be due to their significantly lower levels of cholesterol.

Atherosclerosis begins early in life in Western nations.  Even teenagers have been found to have deposits of atherosclerotic fatty streaks on the inner walls of their arteries.  The higher the blood cholesterol levels are the worse the problem is.  Five percent of all heart attacks occur in people under the age of 40, and 45 percent of all heart attacks occur in people under the age of 65.  The ideal goal for total cholesterol is 100 plus your age.

Multiple Risk Factor Intervention Trial (MRFIT): Among 300,000 men studied, the risk of death from heart disease began to increase when total cholesterol exceeded 150 mg/dl.

Cholesterol’s Subtypes:  HDL and LDL

Cholesterol always travels in different carriers or vehicles in the arteries and veins.  Each type of vehicle has a different weight or density.  The heaviest carriers of cholesterol are called high density lipoprotein (HDL).  Some lighter weight carriers are named low density lipoprotein (LDL), while a still lighter vehicle is called very low density lipoprotein (VLDL).

HDL actually protects us from heart disease—it removes cholesterol from the arteries then carries that cholesterol to the liver, where the body disposes of the fatty material through the bile. 

Study:  In men with HDLs greater than 75 mg/dl there was not a single heart attack, but when the HDL was less than 25 mg/dl, the risk of heart attack was very high.  Women with an HDL cholesterol greater than 75 mg/dl also had low risk of heart disease.  Those with HDLs less than 35 mg/dl had a dramatic rise in their coronary heart disease risk.

LDL is the so-called “bad cholesterol” that is linked to an increased risk of heart disease.  It is probably oxidized cholesterol within LDL that is the culprit.  The level of LDL in the blood is an important determinant of the rate at which cholesterol is deposited in the artery walls. 

Ratios of Total to HDL Cholesterol are better indicator of heart disease risk than looking at either value alone. 

Vegetarians usually have an average total cholesterol to HDL ratio that is low. 

The following guidelines help achieve this goal:

1. Avoid animal products. 

Only animal products contain cholesterol; plant foods do not.  Animal products also contain saturated fats; most plant foods do not.  Both cholesterol and saturated fats contribute to atherosclerosis, hypertension, and heart disease. Serum cholesterol is extremely dependent on the type of protein consumed.  Animal protein alone (even skim milk protein) will increase blood cholesterol levels while plant proteins will decrease cholesterol.  Sometimes lowering cholesterol is difficult or impossible until all animal protein is excluded from the diet.

2.  Avoid hydrogenated oils like margarine (in subjects who replaced margarine on their bread by canola or olive oil,
there was a distinct rise in HDL and slight decrease in LDL).
3.  Eat a high fiber diet consisting of whole grains, fresh fruits and vegetables. 

75% of the cholesterol made in the liver is used to make bile acids.  These bile acids go to the small intestines to emulsify (break down) fats.

Low Fiber Diet:  The bile acids are then reabsorbed into blood stream and go back to the liver where they are reused.  There is no need for the liver to use cholesterol to make more bile acids.  Therefore, the cholesterol in our liver and bloodstream continues to increase.

High Fiber Diet:  Fiber from the food we eat then combines with these bile acids and they are carried out of our bodies during with the feces.  More cholesterol is transformed into bile acids to replace the bile acids that are excreted, therefore lowering the total body pool of cholesterol.

Study:  Found that adding 15 grams of fiber per day to the diet lowered serum cholesterol by 15 percent.  Those that consume a high fiber diet have a 65 percent less risk of heart disease.  Soluble fiber as found in oats is best for lowering cholesterol.
Regular use of garlic helps lower LDL cholesterol and triglycerides.

4.  Add Omega-3 fats to your diet. 

Omega-3’s help to decrease stickiness of platelets, tend to decrease blood pressure, decrease serum triglycerides, decrease damage from heart attacks, decrease likelihood of blood vessels blocking up again after angioplasty or bypass surgery.

5.  Avoid oxidized cholesterol.  Stored foods that contain cholesterol can combine with oxygen in the air and be “oxidized.”  Oxidized cholesterol, even in small amounts, has a lethal damaging effect on arterial walls. May be found in dried egg and milk (found in packaged cake mixes, etc.), parmesan cheese, ice cream, custards, and other products containing eggs, milk, and sugar especially.

6.     Keep triglycerides low.

High triglycerides (fat in the bloodstream) are a risk factor for heart disease.  The following guidelines help lower triglycerides, boost HDL cholesterol and lower the risk of heart disease:  lose weight (down to ideal weight), exercise, eat less fat, decrease stress, stop smoking, abstain from alcohol, and avoid sugar.

Tips to maintain a low fat diet:

Avoid fried foods; sauté in water instead of oil.  You may in moderation safely use Extra Virgin Olive Oil.  Olive oil is monounsaturated and contains the beneficial Oleic Acid.  It has the following properties:
Does not contribute to atherosclerosis
Stabilizes blood sugar curve—polyphenolics in olives can lower high blood sugar
Increases production of prostacyclin—protects against the formation of undesirable blood clots and                              helps lower high blood pressure
Does not contribute to tumor growth
High in antioxidants—Vit E, tyrosol & 3-hydrox-tyrosol protects cell membranes against damage
from free radicals
Blocks absorption of cholesterol and promotes excretion of cholesterol through the bowels.           
Not associated with gallstones
Protects the stomach and intestinal lining

Avoid lots of refined sugar - it increases insulin production which tends to increase fats and cholesterol in the bloodstream, thereby thickening the blood.  This may contribute to diabetes as well as cardiovascular disease and hypertension.

Higher amounts of iron stored in the body increase the risk of heart disease.  Iron is a stimulant of oxidation and may increase the conversion of normal cholesterol into oxidized cholesterol.  Iron also promotes higher hemoglobin levels which means more oxygen in the blood.  This may provide fuel for the oxidation that iron stimulates.  Higher hemoglobin levels also make the blood thicker and more likely to clot and initiate a heart attack.  Too much meat or iron supplements can contribute to this problem.

Antioxidants help prevent oxidation of cholesterol.  These include Vitamins E, C, and beta-carotene as well as many phytochemicals.  Vitamin E has been found to reduce one’s risk of heart disease.  40,000 men were categorized as to the amount of daily Vit. E intake.  Those who consumed 60 IU per day decreased their risk of heart disease by 34 to 50 percent.  Good sources of Vitamin E are wheat germ, vegetable oils, legumes, nuts (particularly almonds), whole grains, and green leafy vegetables.  A Harvard Univ. study found that the consumption of beta-carotene foods reduced cardiac deaths.  Over a period of nearly 5 years, some 1300 individuals were studied.  Results showed that an increased consumption of fruits and vegetables high in beta-carotene decreased subsequent cardiovascular disease deaths.  However, taking supplements of beta-carotene did not lower the risk of heart disease. 

7.     Keep homocysteine levels in the bloodstream low.

Homocysteine is one of the amino acids that the body uses to construct proteins.  Researchers have now found that individuals with high levels of homocysteine in their bloodstreams are twice as likely to have clogged arteries.  For every 10% rise in blood homocysteine levels, heart disease risk goes up roughly 10% as well. 

A healthy lifestyle can beneficially decrease blood homocysteine levels.
·         Coffee drinkers and smokers have high blood levels of homocysteine. 
·         Folate and Vitamins B6 and B12 in the diet get rid of homocysteine by converting it to methionine.  Obtaining at least 400 mcg/day of folate in fruits and vegetables may reduce the risk of heart attack and stroke by up to 40%.  Good vegetarian sources of B6 are bell peppers, sweet potatoes, English walnuts, Brussels sprouts, bananas, garbanzo beans, sunflower seeds, sesame seeds, and rice bran.  Sources of folate are parsnips, pineapple, oranges, peanuts, green leafy vegetables, legumes, and okra.
·         Excessive amounts of methionine can be converted by the body to homocysteine.  Foods containing high levels of methionine include eggs, cheese, beef, fowl, and fish.

2. Exercise Regularly

Exercise has been shown to raise HDL levels (HDL extracts the bad cholesterol from the arteries and helps protect the arteries from damage).  The exercise should be active or aerobic to increase the heart rate and deep breathing.  The more aerobic exercise obtained the greater the rise in HDL.  Exercise strengthens the heart muscle, helps control stress, clears fats from the blood, and lowers blood pressure by increasing circulation.

3. Lower Stress Levels

            Stress is a risk factor for heart attacks. 

Study:  129 heart attack survivors were questioned about everything that happened to them in the 26 hours before the attack.  Serious stress was experienced by 51 percent.  Individuals with pre-existing heart disease more than double their risk of myocardial infarction when they get angry.  This increased risk continues for two hours after the anger episode.  Stress can cause heart arteries to go into spasm.  As a result, when the body’s clotting cells, the platelets, try to pass through that artery they are restrained and clot more easily.

4.  Do Not Smoke

Atherosclerosis is greatly increased in smokers.  Studies show that those who are between the ages of 45 and 54 and smoke more than one pack per day increase their risk of a heart attack by over 4 times.  Older smokers increase their risk between 70 and 200 percent depending on their age.  Nicotine in cigarettes increases the risk of sudden death by predisposing to fatal heart rhythm problems.  Smoking causes platelets to become stickier and clump together in an unnatural way; in the coronary arteries or blood vessels going to the brain, this could stop the flow of blood affecting control of limbs, speech, and even resulting in sudden death.  Smoking greatly increases your risk of a stroke.

5.  Avoid Alcohol

Alcohol is clearly linked cardiovascular problems:

·         It may produce High blood pressure.
·         Alcohol increases the risk of both common types of strokes:  Hemorrhagic stroke caused by bleeding in and around the brain, and the thrombotic stroke caused by blood clots.
·         Cardiomyopathy (heart muscle disease):  Heart muscles do not work as hard as they should because of alcohol consumption.  As a result, fluid builds up in the lungs and then in other parts of the body. 
·         Cardiac arrhythmias may be minor (fluttering sensations in the chest) or major (sudden death).
·         May cause significant triglyceride elevation.

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