Читать книгу Understanding Anatomy and Physiology in Nursing - John Knight - Страница 116

Coronary artery disease (CAD) is the leading cause of heart disease in the UK and worldwide (Bailey and Hall, 2006). The most common form of CAD is caused by atherosclerotic occlusion which is characterised by a slow build-up of fatty plaque which progressively hardens and occludes the vessels. The process of atherosclerotic occlusion usually follows damage to the delicate endothelial layer that is in contact with the blood. Today many factors are known to cause endothelial damage and therefore to precipitate and accelerate atherosclerosis, including smoking, high blood pressure and high blood glucose, e.g. in patients with diabetes mellitus.

During this process the diameter of the coronary arteries is significantly reduced by a gradual build-up of fatty plaque. Atherosclerotic plaque is dense and has a consistency similar to candle wax which causes a hardening to the vessel wall and reduction in the flexibility of the artery. CAD by itself is the greatest single cause of death in the UK; the figures from 2012 indicate 16 per cent of male deaths and 10 per cent of female deaths were from CAD (predominantly as a result of MI) and this equates to around 74,000 deaths (British Heart Foundation, 2014). CAD is usually diagnosed using a stress ECG (S-T depression) and subsequent angiography which allows the diameter of the coronary arteries to be visualised.