Angina pectoris

Angina pectoris is the medical term for chest pain or discomfort due to coronary heart disease. Angina is a symptom of a condition called myocardial ischemia. It occurs when the heart muscle (myocardium) doesn't get as much blood as it needs. This usually happens because one or more of the heart's arteries (coronary blood vessels that supply blood to the heart muscle) is narrowed or blocked. Insufficient blood supply is called ischemia.

Angina also can occur in people with valvular heart disease, hypertrophic cardiomyopathy (this is an enlarged heart due to disease) or uncontrolled high blood pressure. These cases are rare, though. Typical angina is uncomfortable pressure, fullness, squeezing or pain in the centre of the chest. The discomfort may also be felt in the neck, jaw, shoulder, back or arm. Many types of chest discomfort aren't related to angina. Acid reflux (heartburn) and lung infection or inflammation are examples.

Angina often occurs when the heart needs more blood. For example, running to catch a bus could trigger an attack of angina while walking might not. Angina may happen during exercise, strong emotions or extreme temperatures. Some people, such as those who experience coronary artery spasm, may have angina when they are resting. Angina is a sign that someone is at increased risk of heart attack, cardiac arrest and sudden cardiac death.

People with stable angina (or chronic stable angina) have episodes of chest discomfort that are usually predictable. They occur on exertion (such as running to catch a bus) or under mental or emotional stress. Normally the chest discomfort is relieved with rest, nitroglycerin or both.

People with episodes of chest discomfort should see their physician for an evaluation. The doctor will evaluate the person's medical history and risk factors, conduct a physical exam, order a chest X-ray and take an electrocardiogram (ECG). Some people will also need an exercise ECG (stress test), an echocardiogram or other tests to complete the diagnosis.

In people with unstable angina, the chest pain is unexpected and usually occurs while at rest. The discomfort may be more severe and prolonged than typical angina or be the first time a person has angina. The most common cause is reduced blood flow to the heart muscle because the coronary arteries are narrowed by fatty buildups (atherosclerosis). An artery may be abnormally constricted or partially blocked by a blood clot. Inflammation, infection and secondary causes can also lead to unstable angina. Unstable angina is an acute coronary syndrome and should be treated as an emergency. People with new, worsening or persistent chest discomfort should be evaluated in a hospital emergency department or "chest pain unit" and monitored carefully. They are at increased risk for:

• acute myocardial infarction (heart attack);

• severe cardiac arrhythmias. These may include ventricular tachycardia and fibrillation;

• cardiac arrest leading to sudden death.

Cancer

The word cancer actually refers to many diseases, not one. In fact, there are more than 100 types of diseases known collectively as cancer. What they all have in common is the overgrowth of cells, tiny units that make up all living things. Cancer occurs when cells begin to grow and multiply in an uncontrolled way.

Normal body cells grow and divide over a period of time until they eventually die. But cancer cells continue to grow and divide and grow and divide. Eventually, they gather to form tumours. Tumours are lumps that can interfere with the body's normal processes. Sometimes cells from a tumour break away and travel to a different tissue or organ. This is called metastasis.

No one really knows why cancer grows in certain people. Scientists and researchers are working to discover why some people get cancer and others do not. This will help them to learn whether cancer can be prevented.

Doctors do have some ideas about why people may get cancer, though. The main reasons are genetics and certain environmental or behavioural triggers.

Some behavioural and environmental triggers can cause changes in the body's cells that push them into a cancerous state. For example, cigarettes are known to increase the risk of lung cancer. Too much exposure to the sun can increase the risk of skin cancer. These types of triggers act on the body slowly over time, so the cancers that may result from them don't show up until a person is an adult. Doctors do know for sure that cancer itself is not contagious, so you don't have to worry about catching it from someone else or spreading it to another person (although people with certain infectious diseases such as AIDS or hepatitis are more vulnerable to certain cancers). Cancer is also never a person's fault. It's simply not true that a person may have done something wrong to get the disease.

The first sign of cancer is a symptom - a signal that something is wrong. There are many different signs that a person may have cancer, just as there are many different forms of the disease. A few of the more common symptoms of cancer include: extreme exhaustion, swelling or lumps in certain parts of the body, such as the abdomen or neck, headaches, blurred vision, nausea, problems with walking or balance, more infections, unusual bleeding.

Only you know how your body works and what you feel like when you are healthy. If you haven't been feeling well, it's best to see a doctor who will evaluate your symptoms. Cancer, like most illnesses, is easier to treat when it's found early, so when in doubt, check it out.

If a doctor suspects that a person has cancer, he or she will order various tests. These might include blood tests, in which doctors examine blood cells under a microscope to look for problems, X-rays, a test that can be used to detect tumours. Doctors also often use a biopsy to diagnose cancer. In this procedure, a doctor removes a small tissue sample to examine it for cancer cells.

Most cancers can be treated, especially the types of cancers teens are likely to get. The number of people who beat cancer goes up every year because of new cancer treatments. There are three common methods for treating cancer: surgery, chemotherapy, and radiation.