Pathology of Cardiovascular Diseases U3

CVD is a general term that describes a disease of the heart or blood vessels.

Coronary Heart Disease Stroke Peripheral Vascular Disease Aortic Disease

Lack of physical activity Diet high is saturated fats/salt Obesity Smoking Family history (genetic factors)

The accumulation of fatty material, consisting of mainly cholesterol, fibrous material and calcium, forming an atheroma or plaque beneath the endothelium. As the atheroma grows, the artery thickens and loses elasticity. The diameter of the lumen becomes reduced and blood flow becomes restricted, resulting in increased blood pressure. Root cause of Angina, Heart Attacks, Strokes and Peripheral Vascular Disease.

Thrombosis = Formation of a blood clot. Thrombus = A blood clot. Atheromas may rupture and damage the endothelium. This releases clotting factors e.g., vitamin K which activates a cascade of reactions. The enzyme prothrombin is converted to thrombin. Thrombin then causes fibrinogen to convert into threads of fibrin. Fibrin forms a meshwork which clots the blood and seals the wound and provides a scaffold for the formation of scar tissue.

Thrombosis can occur in an artery in the brain (carotid artery) which causes the individual to suffer a stroke. Thrombosis can occur in the coronary artery which supplies the heart muscle with blood. This will cause a myocardial infarction (MI) which is commonly known as a heart attack. Therefore a lack of oxygen gets to the cells resulting in death of tissues.

In some cases, the thrombus may break loose and form an embolus. An embolus can travel through the bloodstream until it blocks a blood vessel.

PVD is disease of the arteries due to blockage of the arteries other than those of the heart or brain. The arteries of the legs are most commonly affected. When these blood vessels suffer an embolism of this type, blood flow is restricted, and pain is felt in the leg muscles because they are receiving an inadequate supply of oxygen.

DVT is the formation of a thrombus in a vein, most commonly one in the veins of the lower leg. Normally this causes the affected extremity to become swollen. In addition, veins close to the skin surface can become engorged with blood. This clot can break off and result in a pulmonary embolism.

Component of the cell membrane. Used to synthesise sex hormones. All cells synthesise cholesterol but around 25% is synthesised in the liver. People may suffer from elevated blood cholesterol due to having a diet high in saturated fat. Too much cholesterol contributes to the formation of atheromas.

Transport cholesterol around the body. HDL. LDL.

Transport cholesterol from body tissues to liver to be broken down. Prevents high level of cholesterol build up in blood stream. Known as ‘good cholesterol’

Main cholesterol carriers in blood. Transports cholesterol made by liver to body cells. Body cells have LDL receptors. When LDL-cholesterol complex attaches, it is engulfed and then used by that cell.

Regular physical activity Dietary changes (reduce saturated fat intake) Statins (medication inhibiting synthesis of cholesterol by liver) Weight loss (reduction in body fat, increase in lean mass)