By Mohamed Badie Ahmed
According to WHO data published in May 2014, coronary heart disease or coronary artery disease (CAD) deaths in Qatar reached 401 or 17.03 percent of total deaths.
CAD is one of the most dangerous that can cause death, because it leads to narrowing or complete blockage of the blood vessels that supply nutrition to the heart.
Unlike other muscles of the body, the heart is continuously pumping blood, beating around 72 contractions a minute when a person is resting. The heart beat can increase up to 200 a minute during strenuous exercise.
Oxygen and nutrition are primarily carried by blood in the arteries to different parts of the body. This oxygenated blood reaches the heart muscle by coronary arteries, so any reduction in supply or increased demand can potentially lead to damage of heart muscle that have a supply disparity. The heart will be partially deprived of oxygen carried by the blood and this causes the weakness of the continuously working heart muscle.
Consequently, if the coronary arteries are completely blocked, the heart muscle will die and stop functioning and is lethal.
The substances that cause the blockage of coronary arteries are blood clots and circulatory fatty molecules (plaque) orair bubbles.
Blood clots or plaque can be formed in any artery, but when they reach or develop in the arteries supplying the heart, it is called CAD. Over recent years, CAD has started to become more widespread through populations since people are not well aware of its the causes or risk factors.
There are many factors that contribute to an increase in the risk of CAD, but perhaps the three most important factors are — smoking, high blood pressure (hypertension) and high level of cholesterol in the blood (hypercholesterolemia).
Cigarette smoking is one of the most common factors that causes CAD. Cigarette consists of many elements such as nicotine and carbon monoxide that harm the coronary arteries. Nicotine is a chemical substance found in tobacco with an addiction potential. While it is an addictive substance, it increases blood pressure and enhances the body to secrete a hormone called adrenalin that raises the heart beat rate and makes the heart work harder. As a result, the heart starts to be less efficient in performing its function; and this will affect the coronary arteries as they supply the heart with oxygenated blood which increases the risk of developing CAD.
Smoking could also destroy the lining layer of the arteries which leads to the accumulation of fatty material called atheroma, an accumulation of degenerative material in the inner layer of artery walls.
All arteries are elastic in nature to accommodate the blood volume ejected when the heart pumps a beat. When atheroma develops, there is loss of arterial elasticity. The diseased arteries become hard and can shatter like glass if the blood pressure suddenly raises.
Another point related to the effect of cigarette smoking on CAD is in terms of blood clotting. Cigarette has elements that promote blood clotting when it is not needed. For example, nicotine and carbon monoxide increase the heart rate, putting an added stress on the heart. Such situation can increase the chance of CAD.
Smoking also decreases the efficiency of blood vessels to expand (dilate), the arteries will be narrow and plaque can accumulate easily, causing narrowing or blockage to the blood vessels that supply the heart.
The second risk factor that can lead to coronary artery atherosclerosis and cause CAD is hypertension, which is a widespread disease, can affect any person and cause a lot of damage to the cardiovascular system.
Prolonged hypertension stresses the blood vessels and causes them to weaken. Additionally, it can narrow the blood vessels and increase the probability of developing blood clots. Blood vessels also can accumulate plaque, which leads to CAD as it happens in the heart blood vessels.
Nowadays, doctors routinely measure blood pressure of patients to predict if they are at any risk of developing cardiovascular diseases. The normal blood pressure range is between 120/80 and 140/90mm of mercury. Although it gives doctors a good indication about patients’ health, only measuring blood pressure is not enough to predict cardiovascular diseases risks.
In addition, narrowing of the blood vessels due to prolonged untreated hypertension decreases the oxygen supply to that region of the heart. The factors can accumulate leading to sudden and complete blockade of blood supply to the heart.
A similar event in the brain is called a stroke. The difference between a heart attack and stroke is that a heart attack is the damage of the heart muscle while stroke is either the entire blockage of a blood vessel that supply the brain or the rupture of a blood vessel within it causing brain tissue to die.
High blood cholesterol level or hypercholesterolemia is a major risk factor that causes the development of CAD. There are two types of cholesterol: HDL (high density lipoprotein) and LDL (low density lipoprotein). HDL is a good and LDL is a bad cholesterol. LDL leads to increase in the stiffness of large arteries and raises blood pressure. Stiffness of the arteries causes their walls to become rigid and lose their elasticity, they lose their ability to stretch horizontally.
As a result, along with the high blood pressure, arteries narrow which help blood clots to form and develop easier and cause plaque to accumulate easily. Consequently, CAD develops as this happens in the coronary arteries.
In contrast, HDL is reciprocally related to the ability of developing blood clots and the accumulation of plaque which causes CAD. HDL works against LDL in the blood vessels. According to Kumar, Abbas and Jon (2013), “high-density lipoprotein (HDL) (“good cholesterol”) mobilises cholesterol from developing and existing vascular plaques and transports it to the liver for biliary excretion” (p. 336).
LDL helps plaques to accumulate in the vessels where they are called vascular plaques, HDL does the opposite. It prevents the accumulation of plaques inside the vessels by transporting them to the liver to be excreted as bile.
This process stops plaques from accumulating in the vessels and ensures that they are not blocked, so blood vessels will be opened and not blocked and this reduces the risk of developing atherosclerosis in the arteries and CAD from developing.
CAD has become widespread in society. There are many ways that help reduce the risk of developing this disease.
First, quit smoking because smoking is the main risk factor.
Second, active lifestyle plays an important role in keeping the body free from any diseases, so we should exercise at least half an hour a day.
Third, eating fish and using olive oil in the food instead of other oils reduce LDL cholesterol level and increase HDL cholesterol level which keep the heart away from developing coronary artery disease.
Remember that you will live your life once, so try to live it as healthy as you can to enjoy it.
