Atherogenesis and Atherosclerosis

Atherogenesis is a circulatory disease whereby atheromas are formed (plaque build-up) within the artery.  Plaque is a combination of cholesterol, fat, calcium, lipids and other substances within the blood stream.  As time progresses, the plaque hardens, narrowing the arteries.  This is known as atherosclerosis. Consequently, blood flow through the narrowed artery is reduced, limiting the supply of blood to vital organs and bodily tissues.  As atherogenesis can affect any artery within the body, different diseases may develop based on the artery that is affected.  Such diseases include: coronary heart/artery disease, carotid artery disease, peripheral artery disease and chronic kidney disease⁸.

Plaque Rupture

As atherogenesis and atherosclerosis causes plaque to build up and harden within the arteries precipitating thrombi, blood flow to the heart, brain, or the lower extremities is obstructed (depending on the artery affected).  This can further develop into coronary heart/artery disease (heart), ischemic stroke (brain) or peripheral vascular disease (lower extremities).  However, the most common and most discussed of these manifestations is coronary heart/artery disease⁹.  These manifestations occur when the plaque ruptures.  The risk of the plaque rupturing is determined by the type of plaque (composition) rather than the size of the plaque (volume) as only plaques that are rich in soft extracellular lipids are rupture-prone (vulnerable).  Whilst most plaque ruptures are small causing an acute coronary event, the actual vulnerability of the plaque may change over time.  Luckily, the vulnerable plaque components are most likely to regress with treatment¹⁰.

Myocardial Infarction

The processes of atherogenesis, atherosclerosis and plaque rupturing, if left undetected can a myocardial infarction (MI) or “heart attack” if the plaque build-up has occurred in the coronary artery¹¹. MI occurs when the blood supply to heart is completely blocked by the formation of a clot or a blockage due to a loose piece of atheroma (plaque rupturing). If the blood supply to the heart is blocked the cells in the heart begin to die due to the lack of oxygen, causing chest pain (angina). The extent of the blockage and the amount of heart muscle affected will determine whether this malfunction will affect the hearts ability to pump blood¹². The signs of atherogenesis, atherosclerosis and plaque rupturing can be subtle, and most heart attack victims may only feel symptoms in the days leading up to the attack. For 80% of people, the first sign of a heart attack is angina. Other symptoms to be aware of are shortness of breath, anxiety, sweating, light-headedness and temporary changes in vision ¹¹.

Exercise

Regular exercise has a major effect on your circulation and cardiovascular health. Moderate levels of exercise can increase blood flow and reduce the risk of poor circulatory health conditions such as atherosclerosis. Exercise promotes good circulation as it strengthens the heart muscles, lowing the resting heart rate and preventing the build-up of plaque in the arteries. It is important for those with current circulation problems to be vigilant while exercising to ensure they are not over exerting themselves¹³.

Know your healthy fats

Diet changes are important for improving circulatory health. Eating a variety of foods such as lean meats, vegetables, fruits, legumes and whole grains will aid in lowering lipid levels and keep them low. It is recommended that more unsaturated fats are consumed in comparison to saturated fats, as saturated fats raise sdLDL-C levels which can lead to an increased risk of atherosclerosis. On the other hand, unsaturated fats such as monounsaturated or polyunsaturated fats may increase HDL levels and are known as being ‘heart-healthy’. It is recommended to find healthier alternatives for certain foods such as butter and oil¹⁴.

Stop Smoking

Smoking can cause circulatory problems in several ways. Most notably it can cause the carotid arteries (arteries which supply oxygen to the brain) to become filled with plaque. Also, smoking can cause PAD by reducing adequate blood supply to the limbs which can lead to leg pain and possibly amputation. Quitting smoking has been proven to have positive effects on circulation: just 20 minutes after a cigarette, blood pressure decreases and oxygen levels return to normal. Within 24 hours, the chance of a heart attack will have already decreased and after 48 hours, nerve endings deeded by the habit are expected to regenerate, with sense of taste and smell improving also. A year after quitting, the risk of coronary heart disease (CHD) will be halved. After 15 years, a quitter’s risk of CHD is now similar to that of a person who has never smoked¹⁴.