Over 270 000 people suffer heart attacks every year, in the UK. What causes coronary heart disease? How can it be treated and prevented and what are the risk factors?
Coronary heart disease (CHD) is caused by atherosclerosis occurring in the coronary arteries that supply blood to the myocardium. Restriction of blood-flow to this tissue reduces its ability to function; failure of the myocardium can have catastrophic consequences. CHD is multi-factorial; teenagers may start smoking to be accepted by people. British people are more likely to suffer CHD then Japanese people because of the diet based around rice, fish, and potatoes.
High blood pressure (BP) causes tears to the endothelium, fats are laid down and form atheroma. Nicotine in cigarettes increases the BP, causing tears in the endothelium. Carbon Monoxide reduces the amount of oxygen transported in the blood, the heart works faster to maintain the blood supply to body tissues and increases the blood pressure. High saturated fats and cholesterol in the blood cause the release of low-density lipoproteins (LDL), which are lipids combined with proteins that are laid down in the arteries forming atheroma. High salt levels in the bloodstream raise the HR, causing atherosclerosis. High sugar levels leads to diabetes and obesity, these are both risk factors for CHD.
Exercise increases the metabolic rate; burns up fats and sugars in the blood for respiration. If people do not get enough exercise fats are laid down into the arterial walls, forming atheroma. Older people lose elasticity in their arteries resulting in a higher BP. Older people are not as active and do not generally participate in as much exercise, also more time has elapsed over the years for atheroma to accumulate in the arteries. The likelihood of obesity in older people is greater because they have a lower metabolic rate then younger generations. Men are more likely to get CHD because the female hormone oestrogen prevents damage to the endothelium reducing the chances of CHD in women. People can inherit high cholesterol levels genetically e.g. hypercholesterolemia. They have higher LDL levels then average people and therefore more chance of developing CHD.
Treatments for CHD include; changes to a person’s diet, exercise, drugs and surgery. Patients can monitor their intake of fats with low fat diets. Lower concentrations of saturated fats in a diet reduce the release of LDL into the blood. Increasing intake of fibre absorbs fats in the diet preventing them being absorbed into the bloodstream. An increase in complex carbohydrates in the diet lowers blood sugar concentration, reducing BP and HR. Exercise is a simple/cost effective treatment for suffers of CHD. The increased HR and metabolic rate means more of the body’s food intake is used for physical activities and burns up fats and sugars in the bloodstream, reducing the number of atheroma in the arteries.
This puts less stress on the heart when resting because it is not required to pump has often to maintain the same supply of blood to the tissues in the body. Patients can be prescribed with drugs to tackle CHD, these drugs are called statins. ‘Statins are a class of drugs that lowers the level of cholesterol in the blood by reducing the production of cholesterol by the liver. Statins block the enzyme in the liver that is responsible for making cholesterol. This enzyme is called hydroxyl-methyl glutaryl-coenzyme a reductase (HMG-CoA reductase for short)’. (1) ‘Inhibition of the enzyme stimulates LDL receptors, resulting in an increased clearance (LDL) from the bloodstream and a decrease in blood cholesterol levels’. (2) ‘Scientifically, statins are referred to as HMG-CoA reductase inhibitors’. (1) The decrease in cholesterol level means that the body has a greater chance of burning up saturated fats in the blood. The drop in saturated fats in the blood prevents atheroma forming and clogging the arteries, which would lead onto CHD. This reduces stress on the heart and keeps BP and HR lower.
If CHD becomes has developed too far for statins, exercise or diet change to have a significant effect on their own to solve the problem, various surgical options are available to tackle CHD. The treatment used to combat CHD depends on the symptoms and how far the CHD has developed. If the CHD does not cause symptoms, it can be treated with either medicine or angioplasty. ‘Angioplasty is a medical procedure to open narrowed blood vessels of the heart’, (3) it does not help you live longer, but it can reduce angina or other symptoms of CHD. ‘A catheter is threaded through the blockage, and a thin, un-inflated balloon is passed to the catheter. Once properly positioned in the artery, the balloon is inflated to open the blockage and create a channel that increases blood-flow through the artery’. (4) Once a channel has been created, a stent may be implanted to maintain the opening. The principle behind angioplasty is to improve a patient’s survival and recover the myocardium. If the artery is completely blocked or toward the top of the myocardium, heart bypass surgery is favoured as a treatment to angioplasty.
‘Heart bypass surgery creates a detour or “bypass” around the blocked part of a coronary artery to restore the blood supply to the heart muscle’. A vein, the saphenous vein, is taken from the leg to be used for the bypass. ‘An incision is made in the leg and the vein removed. The vein is located on the inside of the leg, running from the ankle to the groin. The saphenous vein normally does only about 10% of the work of circulating blood from the leg back to the heart. Therefore, it can be taken out without harming the patient or the leg’. The principle of bypass surgery is to restore the flow of blood to the myocardium by creating and alternative route for the blood to flow around the blockage instead of being forced to pass through the block.
If the demand for heart surgery decreases, the NHS requires less funding. This will reduce taxes, meaning there is a greater amount of dispensable income to be spent on recreation and leisure, this leads to better health across the UK, keeping cases of CHD lower, this further reduces NHS costs and mortalities.
The cost of treating CHD is high but 1 in 4 males and 1 in 5 females die from CHD. Early detection and treatment of CHD avoids costly procedures i.e. bypass surgery. Meaning tax payers pay less into the NHS.
The availability of drugs can vary throughout the UK. In some parts of the UK, statins are more widely available; therefore, patients have to wait or travel to receive treatments in a different area, meaning that death rates can vary from area to area. E.g. people in the south west of England may have more access to clot busting drugs and statins and therefore more are treated for CHD then in the North East. Statistics would then show that the southwest is a healthier area than the north east, which is not completely accurate.
There needs to be a greater emphasis on exercise and sport to prevent CHD forming in the population before it starts. Education on diets and eating healthily comes too late to have an impact. A bigger push needs to be made on healthy eating to children at primary school age and less fast foods and foods high in fat and sugar should not be served in schools to pupils or staff to set examples and ideas. This should stop too much sugary and fatty foods being eaten, improving the health of the UK in the long-term.