What is Heart Disease?
Heart disease is a broad term which people use loosely to describe a number of conditions that affect the heart and blood vessels. A more accurate term to use would be “cardiovascular disease” but it’s a bit of a mouthful if you’re not used to medical terms. Cardiovascular disease refers to a collection of conditions which affect the heart (cardio-) and blood vessels (vascular).
The heart is made up of:
- muscle which pumps blood
- valves which keep the blood moving forward
- arteries which supply oxygen and food to the heart muscle
- the pericardium, the outer sac which surrounds the heart
Problems may arise from any of these structures.
Coronary artery disease
This is among the best known forms of cardiovascular disease. It is a condition in which the blood vessels that supply oxygen and food to the heart become blocked and the heart muscle cannot function properly. This eventually leads to a “heart attack” when there is death of the heart muscle.
The most common cause of blockage of the arteries is artherosclerosis, a condition where fat is laid down on the artery walls gradually causing narrowing until blood can’t pass through it anymore. Coronary artery disease eventually leads to coronary heart disease which refers to a condition where disease of the coronary arteries has led to heart symptoms such as chest pain or a heart attack (myocardial infarction).
This means that the heart muscle itself is damaged. This can be due to a heart attack for example.
This affects the valves in the heart and can be due to narrowing or inability of the valves to close properly leading to blood leaking backwards. The strain that is put on the heart muscle eventually leads to cardiomyopathy.
This affects the outer coat of the heart
Congenital heart disease
These are heart conditions that you are born with.
Heart failure (Congestive cardiac failure)
This is a condition in which the heart can’t pump blood effectively around the body. As a result, organs in the body can’t get enough oxygen and nutrients. This can lead to build up of fluid in the tissues when it is then known as congestive cardiac (heart) failure.
Heart failure can be caused by conditions that damage the heart muscles e.g high blood pressure.
High blood pressure (hypertension)
Here the force of the blood moving round in the blood vessels is very high. It can lead to damage of the blood vessels resulting in bleeding e.g. into the brain (leading to a stroke) and the nose leading to a nose bleed.
Arteriosclerosis refers to hardening and thickening of the walls of the arteries. As the artery can’t expand, it reduces the amount of blood it can carry around the body. This is a natural part of the aging process. However, the commonest type of arteriosclerosis is artherosclerosis where hardening of the arteries is caused by fat being laid down on the walls of the arteries.
This is when the brain can’t function properly as a result of death of the brain cells. Strokes can be hemorrhagic (from bleeding into the brain) or ischemic (from blood supply to the brain cells being cut off e.g. in atherosclerosis).
Varicose veins are swollen, twisted veins which occur most commonly in the legs. They arise from damage to the valves in the veins which are supposed to stop blood from flowing backwards. When these valves don’t close properly, it leads to accumulation of blood in the veins making them become enlarged and twisted. Apart from causing varicose veins, incompetent valves and pooling of blood in the arms or legs can also lead to skin ulcers (wounds) and swelling of the legs.
A thrombus is a blood clot. Venous thrombosis happens when a blood clot is formed in the veins, usually in the legs. When part of a blood clot breaks off and moves to another part of the body, it is known as an embolus. It may go on to become stuck in the smaller blood vessels of the lungs (leading to pulmonary embolism) or the brain (leading to a stroke).
With this quick over-view of cardiovascular disease, I hope you will find it less confusing.