• coronary artery disease or narrowing of blood vessels that supply the heart
• peripheral vascular disease or narrowing of arteries other than those that supply the heart or brain and can include small capillaries
• stroke when blood flow to the brain is blocked; the brain does not get enough oxygen and cells begin to die
• heart attack (myocardial infarction or MI) when blood flow to the heart is blocked; heart muscle does not get enough oxygen and cells begin to die.

Conditions caused by cardiovascular disease

• Angina is a symptom of coronary artery disease when the heart does not get enough oxygen and compensates by pumping harder and faster. Symptoms include discomfort or pain in the chest and breathlessness on exertion. Angina is not the same as heart attack as it is not caused by a blockage only a narrowing of the arteries and there is no permanent damage to the heart muscle.

• Congestive heart failure is when the heart does not pump efficiently and cannot maintain adequate circulation of blood. This is because the heart muscle has become weakened and the heart works harder to compensate. It is caused by damage to the heart muscle due to a previous heart attack or prolonged high blood pressure or due to a condition called cardiomyopathy or large heart. Oedema is a symptom of heart failure as fluid collects in the tissues due to poor circulation; also shortness of breath, cough and weakness.

• Atrial fibrillation or irregular heart rhythm, usually a rapid heart beat, has several possible causes. A major cause is prolonged high blood pressure, which results in disturbed blood flow and increases risk of heart failure and stroke. Symptoms include heart palpitations and shortness of breath.

• Thrombosis is when a thrombus or blood clot forms at the site of injury on the blood vessel wall and blocks the flow of blood. Thrombus formation stops bleeding when a blood vessel is injured. It begins with platelet aggregation, which is clumping of platelets; small cell fragments without a nucleus that play an important role in haemostasis (keeping blood flowing in a damaged vessel) by plugging the injury. A common cause is cardiovascular disease, when an artery wall, hardened by build up of cholesterol, ruptures exposing an atherosclerotic plaque and this triggers platelet aggregation. Secondary effects of cardiovascular disease can also cause thrombus formation, such as atrial fibrillation, due to blood pooling in the heart; or high blood pressure which can damage blood vessel walls. The result of a thrombosis depends on where the blockage occurs; if the coronary arteries become blocked this can cause a heart attack; if the arteries to the brain become blocked, this can cause a stroke.

• Thromboembolism or embolism is a thrombus that becomes dislodged from the blood vessel wall and travels in the blood to another site in the body where it may get stuck and block blood flow. The site where the thrombus ends up determines the outcome. If the embolism stops in the lungs it is a pulmonary embolism, if it stops in the coronary artery it can cause a heart attack, or in vessels supplying the brain it can cause a stroke.

Classes of cardiovascular medications

• ACE inhibitors are used to treat hypertension and congestive heart failure and work by inhibiting the action of Angiotensin Converting Enzyme that causes salt and water retention by the kidneys and also causes blood vessel narrowing, which increases blood pressure. The action of ACE inhibitors reduces blood volume, widens blood vessels and lowers blood pressure.

• Calcium channel blockers are used to treat hypertension and angina and work by blocking inflow of calcium ions into smooth muscle cells of blood vessel walls, preventing them from contracting and allowing blood vessels to widen.

• Angiotensin II receptor blockers (ARB) are used to treat hypertension and congestive heart failure and work by blocking the hormone angiotensin II binding to its receptor, which prevents salt and water retention by the kidneys, blood vessel narrowing and increase in blood pressure. The action of ARBs reduces blood volume, widens blood vessels and lowers blood pressure.

• Diuretics are used to treat hypertension and congestive heart failure and work by acting on the kidneys and promoting the excretion of salts and water to reduce blood volume and thereby reducing blood pressure and oedema (fluid retention in the tissues).

• Anti-clotting drugs are used to prevent thrombosis associated with cardiovascular disease and work by inhibiting the binding of a adenosine diphosphate (ADP) to its receptor on platelets and this inhibits platelet aggregation and reduces risk of a clots forming.

• Anticoagulants are used to treat and prevent thrombosis and thromboembolism associated with cardiovascular disease and work by inhibiting the production of Vitamin K dependent blood coagulation factors, which inhibits the coagulation cascade and prevents blood clotting.

• Vasodilators are used to treat poor circulation, hypertension and angina, and act directly on blood vessel walls, causing them to relax and widen, which allows blood to flow more freely.

• Beta blockers are used to treat hypertension, angina and arrhythmias and work by blocking the action of catecholamines such as adrenaline that act on beta receptors in the heart to increase heart rate and narrow blood vessels. The action of beta blockers is to slow heart rate, widen blood vessels, lower blood pressure, and increase blood flow and oxygen to the heart.

Cholesterol lowering medications

• Statins that reduce the production of cholesterol by the liver by inhibiting HMG-CoA reductase, an important enzyme involved in cholesterol synthesis

• Cholesterol absorption inhibitors that act directly on the small intestine to inhibit the intestinal absorption of cholesterol

• Fibrates that activate the enzyme that breaks down lipids in the blood and reduces the production of proteins that transport LDL lipids but increases the production of proteins that transport HDL

Non-prescription supplements