Coronary heart disease is the most common and deadly form of cardiovascular diseases that is caused by narrowed coronary arteries; the blood vessels that supply heart muscle with oxygen and nutrient rich blood.

A damage on the endothelium (innermost layer) of these arteries may happen under the effect of several factors, such as smoking, hypertension and diabetes. This open the door for cholesterol and other particles to adhere to the wall of the blood vessel and build up to make plaque.

If the flow of oxygen-rich blood to the heart muscle is reduced or blocked, angina or a heart attack can occur. Over the time, Coronary heart disease can weaken the heart muscle and lead to heart failure and arrhythmias. This disease is the leading cause of death worldwide.

Having any form of chest discomfort should urge the person to seek medical help and undergo tests that check for coronary heart disease, such as electrocardiogram and angiograms. New, worsening or persistent chest pain should force who has the disease to visit the emergency unit.

Lifestyle changes and some medications can help control coronary heart disease. These changes include a healthy diet, being physically active, maintaining a healthy weight, quitting smoking, and managing stress.

With proper treatment and follow up, the general health outcomes are good and affected people can have good quality of life. Early alertness of coronary heart disease and its subsequent heart attack may push toward assuming life-protecting measures.

Coronary heart disease (CHD) is a major health problem in which a waxy substance called plaque builds up inside the blood vessels that supply oxygen-rich blood to the heart (coronary arteries) in a process called Atherosclerosis that narrows and hardens the arteries. If the plaque ruptures, a blood clot can form on its surface. A blood clot can partially, mostly, or completely block blood flow through a coronary artery causing ischemia or heart attack. Both narrowing and blockage of the blood vessels can trigger symptoms and lead to heart disease.

The main cause of coronary heart disease is a build-up of fatty deposits called atheroma on the walls of the coronary arteries. Atheroma are made up of cholesterol and other waste substances. The buildup of these cause narrowing of the arteries and restrict blood flow to the heart. This process take place under the effect of several factors that can damage the inner layer of coronary arteries. They include:

• High cholesterol levels: this fuels the formation of plaques and atherosclerosis. High cholesterol can be caused by a high level of low-density lipoprotein (LDL) that known as the "bad" cholesterol, or A low level of high-density lipoprotein (HDL), known as the "good" cholesterol.
• Diabetes: The metabolic disease may cause the lining of blood vessels to become thicker, which can restrict blood flow and more than double your risk of developing CHD. Type 2 diabetes and coronary artery disease share similar risk factors, such as obesity and high blood pressure.
• Smoking: This universal bad habit put a strain on the heart by making it work faster. It also increases the risk of blood clots and can damage the lining of coronary arteries, leading to furring of them to become more prone to atherosclerosis.
• Hypertension: Uncontrolled high blood pressure can result in hardening and thickening of the arteries. It also makes heart work harder against elevated forces that lead to further injury.
• Overweight or obesity. Excess weight is associated with a number of comorbidities, including several forms of heart disease. Obese people are more likely to develop hypertension, diabetes and atherosclerosis. These conditions will deepen the risk of cardiovascular disease.
• Physical inactivity. Lack of exercise also is associated with coronary artery disease and some of its risk factors, as well.
• High stress levels. Emotionally upsetting events are the most commonly reported "trigger" for a heart attack. Unrelieved stress in life may worsen other risk factors for coronary artery disease.
• Sleep apnea: This disorder causes repeated stoppage of breathing while sleeping. Sudden drops in blood oxygen levels that occur during sleep apnea increase blood pressure and strain the cardiovascular system, possibly leading to coronary artery disease.
• Age: Getting older increases the risk of damaged and narrowed arteries affected by genetic or lifestyle factors. In men, the risk for CHD increases starting at age 45. In women, the risk start increasing at age 55.
• Sex: Men are generally at greater risk of coronary artery disease. However, the risk for women increases after menopause and they are more prone to die by that disease if they have it.
• Family history: A family history of heart disease is associated with a higher risk of coronary artery disease, especially if the father or a brother was diagnosed with heart disease before age 55 or if the mother or a sister developed it before age 65.
• High sensitivity C-reactive protein (hs-CRP): C-reactive protein is a normal molecule that appears in higher amounts when there's inflammation in the body. High hs-CRP levels may be a risk factor for heart disease as low level of inflammation play a major role in narrowing blood vessels due to build-up of cholesterol and other lipids.
• High homocysteine levels: This amino acid is used by the body to make protein and to build and maintain tissue. But high levels of homocysteine in blood is associated with atherosclerosis and blood clots.

The first stage of coronary heart disease is endothelial damage and dysfunction, which stimulates the accumulation and oxidation of LDL in the artery wall. Monocytes, a type of white blood cells, migrate from the blood into the subendothelial intima and transform into macrophages, which accumulate lipids to form the lipid core of the atherosclerotic plaque.

Thrombotic and inflammatory processes are central to atherosclerotic lesion formation. Production of inflammatory mediators and cytokines stimulate migration and proliferation of smooth muscle cells of the vascular intima, and deposition of extracellular matrix molecules such as elastin and collagen, which leads to plaque expansion and the formation of the fibrous cap. Eventually the fibrous cap may weaken and rupture.

Plaque rupture can cause continued development of the atherosclerotic lesion by inducing further thrombus formation and release of more inflammatory mediators, resulting in continued luminal narrowing. A more drastic outcome of plaque rupture is arterial occlusion, which can result in myocardial infarction.

Coronary heart disease usually develops many years before any clinical symptoms are manifest. Complains may start under the effect of ischemia, in which the blood flow (and thus oxygen) is restricted or reduced to the heart. The main Symptom is Angina, defined as a feeling of pressure, tightness, or squeezing in the chest, usually on the middle or left side. Angina is generally triggered by physical or emotional stress and usually goes away within minutes after stopping the stressful event, whilst several types of angina are expressed in the chart below.

Some people who have coronary heart disease have no signs or symptoms - a condition called silent CHD. The disease might not be diagnosed until a person has signs or symptoms of a heart attack, heart failure, or an arrhythmia (an irregular heartbeat). Heart attack is a completely blocked coronary artery that noticed by sever, acute pressure in chest and pain in the shoulder or arm, sometimes with shortness of breath, sweating and nausea.

After taking medical history, doing physical exams, the doctor may suggest one or more of the following diagnostic tests to check or confirm coronary heart disease.

• Electrocardiogram (ECG): A simple, painless test that detects and records the heart's electrical activity. The test shows heart rate and rhythm. ECG can also show signs of heart damage due to CHD and signs of a previous or current heart attack.
• Echocardiogram. An echocardiogram uses sound waves to produce images of the heart. During the test, the doctor can determine whether all parts of the heart wall are contributing normally to heart's pumping activity. Parts that move weakly may have been damaged during a heart attack or be receiving too little oxygen. This may indicate coronary artery disease or various other conditions.
• Stress Testing. This test examines how the heart functions during activity. When the heart is working hard and beating fast, it needs more blood and oxygen. Plaque-narrowed arteries can't supply enough oxygen-rich blood to meet heart's needs. In the test, Deferent readings are taken while the person are exercising in the outpatient clinic. If he can't exercise, a medication may be given to raise the heart rate. Possible signs and symptoms of CHD include Shortness of breath, chest pain, and abnormal changes in the heart rate, rhythm, or electrical activity.
• X-Ray imaging: A chest x-ray takes pictures of the organs and structures inside the chest, such as the heart, lungs, and blood vessels. It can reveal signs of heart failure, as well as lung disorders and other causes of symptoms not related to CHD.
• Blood Tests: Blood tests check the levels of certain fats, cholesterol, sugar, and proteins in the blood. Abnormal levels might be a sign that the person at risk for CHD or he/she may indeed have this disease. A high-sensitivity C-reactive protein (hs-CRP) test may be used in combination with a lipid profile or with other cardiac risk markers, such as a lipoprotein-associated phospholipase A2 (Lp-PLA2) test.
• Cardiac catheterization: Passing a thin flexible tube (catheter) into the coronary artery can help to detect the problem and may be used to deal with it. If there is a blockage that requires treatment, a balloon can be pushed through the catheter and inflated to improve the blood flow in the coronary arteries. A stent may then be used to keep the dilated artery open.
• Angiogram: To view blood flow through the heart vessels, the doctor may inject a special dye into coronary arteries through a catheter that is threaded through an artery, usually in the leg, to the targeted blood vessel. Then, x-ray or CT scan is taken to determine the narrowed and clogged parts. Angiogram is considered the gold standard for evaluating blockages in the arterial system.
• Heart scans. A Magnetic Resonance (MRI) scan can be used to produce detailed pictures of the heart. Computerized tomography (CT) technologies can help the doctor to see calcium deposits in the arteries that can narrow them. If a substantial amount of calcium is discovered, coronary artery disease may be likely.

Although coronary heart disease cannot be cured completely, treatment can help manage the symptoms and reduce the risk of further problems. Treatment usually involves lifestyle changes and, if necessary, drugs and certain medical procedures.

• Lifestyle Changes
  • Heart-Healthy Diet: A lot of foods are good for the heart and the body. Monounsaturated and polyunsaturated fatty acids actually help lower blood cholesterol levels. Examples of these foods are avocado, nuts, seeds, tofu and some oils (olive, canola, peanut, safflower and sesame). Eating Fish high in omega-3 fatty acids, such as salmon, tuna, and trout, is recommended about twice a week. High fiber foods play another major role in controlling and reducing the risk of coronary heart disease. They can decrease serum total and low-density lipoprotein (LDL) concentrations and improve insulin resistance. Fiber-rich Foods include fruits, legumes, vegetables and whole grains. Healthy eating includes also avoiding some foods that considered bad for heath. Heart patients are advised to limit their intake of red meat, Palm and coconut oils, sugary foods and beverages, salt, alcohol and trans-fat, which is found in products made with hydrogenated oils and fats, that could be found at stick margarine, baked goods and coffee creamers.
  • Maintaining a Healthy Weight: having normal body weight is important for overall health and can lower the risk for coronary heart disease. This can be achieved by following a heart-healthy eating plan and keeping physically active. A general goal to aim for is a BMI of less than 25 and a waist circumference that is less than 35 inches for women or less than 40 inches for men. If the person is overweight or obese, a loss of just 3-5% of current weight can lower triglycerides, blood glucose, and the risk of developing type 2 diabetes. Greater amounts of weight loss can improve blood pressure readings, lower LDL cholesterol, and increase HDL cholesterol.
  • Physical Activity: Regular exercising can lower many coronary heart disease risk factors, including LDL cholesterol, high blood pressure, and excess weight. Physical activity also can lower the risk for diabetes and raise HDL cholesterol level. Talking with the doctor before starting a new exercise plan is preferred. The person should ask the doctor how much and what kinds of physical activity are safe and effective for him/her. The general target is 150 minutes moderate-intensity aerobic physical activity per week or 75 minutes a week of vigorous-intensity aerobic physical activity or a combination of the two with muscle-strengthening for at least 2 days per week.
  • Give up smoking: Smoking is a major risk factor for developing atherosclerosis. It also causes the majority of cases of coronary thrombosis in people under the age of 50. If the person has a trouble quitting smoking on his own, he has to talk with his doctor about programs and products that can help quitting. Support group in hospitals, workplaces, or community groups offer classes to help people quit smoking.
  • Stress Management: Learning how to manage stress, relax, and cope with problems can improve emotional and physical health. Meditation, Physical activity and deep breathing are of these helpful techniques that also boosts cardiovascular health, in contrast to bad ways to cope with stress - such as drinking, smoking, or overeating – that worsen the problem inside the arteries.
  • Controlling chronic illnesses: If the patient has hypertension, he should aim to manage this condition with healthy life style, limiting sodium intake and taking prescribed medications. Maintaining blood glucose levels within targeted levels in case of diabetes will help prevent worsening of the problem. For those who have both conditions, blood pressure levels should be below 130/80mmHg.
• Medications

Besides lifestyle changes, various drugs can be used to manage the coronary heart disease and decrease the chance of having a heart attack or stroke. They also can help delaying the need for surgical procedures. These include:

• • Cholesterol Lowering Medications. By decreasing the amount of low-density lipoprotein (LDL, or the "bad") cholesterol, these drugs decrease the row material that deposits on the coronary arteries. The doctor can choose from a range of medications, including statins, fibrates and bile acid sequestrants.
  • Aspirin. The doctor may recommend taking a daily aspirin or other blood thinner. This can reduce the tendency of blood to clot, which may help prevent obstruction of coronary arteries. If the person has had a heart attack, aspirin can help prevent future episodes.
  • Beta blockers. These drugs slow the heart rate and decrease blood pressure, which decreases heart's demand for oxygen. Also, they reduce the risk of future heart attacks for whom had before. Examples of these: Acebutolol and Atenolol.
  • Nitroglycerin. Exists is several forms (tablets, sprays and patches) and can help in controlling chest pain by temporarily dilating coronary arteries and reducing heart's demand for blood. It is used sublingually as a first aid in cases of myocardial infarction.
  • Angiotensin-converting enzyme (ACE) inhibitors. These drugs decrease blood pressure and may help prevent progression of coronary artery disease. Examples: Lisinopril, Benazepril and Captopril.
  • Angiotensin II receptor blockers (ARBs). Help to reduce blood pressure and improve blood flow. They may be used instead of ACE inhibitors if the last are not tolerated, especially for the annoying cough. Examples: candesartan, irbesartan and losartan.

Patients are advised to take all medications regularly, as the doctor prescribes. They should not change the amount of the drug or skip a dose unless the doctor tells them. They still have to follow a heart healthy lifestyle, even if they take medications to treat coronary heart disease.

• Medical Procedures and Surgery

If neither healthy habits nor medications are enough to control the coronary heart disease, there may be a need for procedures or surgeries to treat the problem. The main two of them are:

• • Percutaneous coronary revascularization (Angioplasty). In this nonsurgical procedure, the doctor inserts a catheter through an artery in the upper thigh or arm until reaching the narrowed part of the coronary artery. A wire with a deflated balloon is passed through the catheter. The balloon is then inflated, compressing the deposits against artery walls. A stent is often left in the artery to help prevent blockages in the artery in the months or years after the procedure. Some stents slowly release medication to help keep the artery open.
  • Coronary artery bypass grafting (CABG). A surgical procedure in which arteries or veins from other areas in the body are used to go around the narrowed parts of the coronary arteries. CABG can improve blood flow to the heart, relieve chest pain, and possibly prevent a heart attack. Because this requires open-heart surgery, it is most often reserved for cases of multiple narrowed coronary arteries.

Without detection and controlling, coronary heart disease can progress into very serious health conditions that may be fetal if not treated duly and immediately. Major complications for (CHD) are:

• Heart failure. One of the most common complications of heart disease, heart failure occurs when the heart can't pump enough blood to meet body's needs. It can affect the right, left, or both sides of the heart.
• Heart attack. A blood clot blocking the blood flow through a blood vessel that feeds the heart causes a heart attack, possibly damaging or destroying a part of the heart muscle and may cause death if the affected part was large or no action has been taken. The degree of loss of heart function after recovery depends on the size and location of the scar tissue in the site of injury.
• Stroke. The risk factors that lead to cardiovascular disease also can lead to an ischemic stroke, which happens when the arteries to the brain are narrowed or blocked so that too little blood reaches that sensitive organ. A stroke is a medical emergency as brain tissue begins to die within just a few minutes of it.
• Aneurysm. A bulge in the wall of the artery that can occur anywhere in the body. An aneurysm is a serious complication as it can burst and cause life-threatening internal bleeding.
• Peripheral artery disease. A progressive atherosclerotic condition that causes stenosis and occlusion of non-cerebral and non-coronary arteries. In this case, the extremities don't receive enough blood flow. The main symptom of this case is leg pain when walking.
• Sudden cardiac death (SCD). An unexpected loss of heart function, breathing and consciousness, often happens when the electrical system to the heart malfunctions and suddenly becomes very irregular. SCD is a medical emergency that could be fatal if not treated immediately.

What has been mentioned in the heart healthy life style for treating coronary artery disease can also help prevent it from developing in the first place. This is completely true for modifiable risk factor, such as obesity, Diabetes and hypertension. Only a few risk factors - such as age, gender, and family history -can’t be controlled. Even though leading a healthy lifestyle can help keep arteries strong and clear of plaques.

Some preventive measures that can be added to the list above:

• Workplace-wellness initiatives: As most employees spend more than half of their waking hours at work, promoting health among them can play an important role in fighting heart disease and stroke.
• Improving recognition of symptoms and treatment for heart disease and attack: several cardiac biomarkers are well-known to determine these conditions. Having any kind of chest pain should enhance the person to seek medical help and undergo recommended test.
• Getting enough sleep (7-9 hours a day for adults): a link had been determined between shortened sleep and increased coronary artery calcification; a predictor of subsequent coronary artery disease. Treating sleep apnea may also reduce the risk.

Coronary heart disease may run silently without symptoms until sever conditions develop. Early detection of CHD generally leads to better outcomes. Some people can stay healthy by changing their diet, quitting smoking, and taking their medications as prescribed. Others may need medical procedures such as angioplasty or surgery.

Patients have to Work closely with their doctors to control blood pressure and manage blood cholesterol, sugar levels. Regular visits and tests may help assess disease management to take the correspondent actions that reduce the risk of further complications.

The global impact of non-communicable diseases, which includes cardiovascular disease (CVD), diabetes, chronic respiratory diseases and cancers, on the social and economic development of all United Nations countries is enormous. They are responsible for 60 per cent of deaths worldwide and half of these can be attributed to CVD, making it the world’s number one killer.

Coronary heart disease (CHD) is a major type of CVD that considered the leading single cause of death around the world. According to world health organization (WHO) an estimated 7.4 million death in 2012 were due to CHD. Over three quarters of CVD deaths take place in low- and middle-income countries. In these countries these Diseases compose 37% of total deaths.

Even coronary heart disease is more prevalent in men, women have greater death rates by this disease, as they are less tending to face the major symptom of heart attach; i.e. chest pain, compared to men. Women are more likely to have symptoms such as shortness of breath, nausea and extreme fatigue, which may be referred by them and their doctors to other than heart attack.