Coronary heart disease

What is coronary heart disease?

Coronary heart disease (CHD) or coronary artery disease is the narrowing of the small blood vessels (coronary arteries) that supply blood and oxygen to the heart. Coronary disease usually results from the build up of fatty material and plaque (atherosclerosis). As the coronary arteries narrow, the flow of blood to the heart can slow or stop. This results in chest pain (angina), shortness of breath, heart attack, or other symptoms.

What are the causes?

CHD can run in the family. It might develop as one gets older or if one is overweight, has high blood pressure, high cholesterol or diabetes. Unhealthy habits, like smoking, eating a diet high in fat and not exercising enough, can also cause CHD.
Risk factors for CHD include the following:

Family history of coronary heart disease (especially before age 50)
Male gender
Age (65 and greater)
Tobacco smoking
High blood pressure
High cholesterol levels (specifically high LDL cholesterol and low HDL cholesterol)
Lack of physical activity or exercise
High blood homocysteine levels
Menopause in women

What are the symptoms?

The symptoms associated with coronary heart disease may be pronounced, but it can also be present without any noticeable symptoms.

(Chest pain (angina)) - This is the most common symptom, and it results from the heart not getting enough blood or oxygen. The intensity of the pain varies from person to person. Chest pain may be typical or atypical. Typical chest pain is felt under the sternum (breast bone) and is characterised by a heavy or squeezing feeling. It is precipitated by exertion or emotion, and it is relieved by rest or nitroglycerin. Atypical chest pain can be located in the left chest, abdomen, back, or arm and is fleeting or sharp. Atypical chest pain is unrelated to exercise and is not relieved by rest or nitroglycerin. Atypical chest pain is more common in women.

Other symptoms include:

(Shortness of breath) - This is usually a symptom of congestive heart failure. The heart at this point is weak because of the long-term lack of blood and oxygen, or sometimes from a recent or past heart attack. If the heart is not pumping enough blood to circulate in the body, shortness of breath may be accompanied by swollen feet and ankles.

(Heart attack) - In some cases, the first sign of CHD is a heart attack. This occurs when atherosclerotic plaque or a blood clot blocks the blood flow of the coronary artery to the heart. The coronary artery was likely already narrowed from CHD. The pain associated with a heart attack is usually severe, lasts longer than the chest pain described above, and is not relieved by resting or nitroglycerin.

How is it diagnosed?

There are many tests that may help to diagnose CHD. Usually, more than one test will be done before a definitive diagnosis can be made. Some of the tests include:
Electrocardiogram (ECG)
Exercise stress test
Nuclear scan
Coronary angiography
Electron-beam computed tomography (EBCT) - the purpose of this test is to identify calcium within the plaque found in the arteries. The more calcium seen, the higher the likelihood for CHD.

What is the treatment?

The treatment for CHD varies depending on the symptoms and how much the disease has progressed. General treatments include lifestyle changes, medications, and sometimes surgery.

Lifestyle changes may include:

A weight reduction programme
A low saturated fat, low cholesterol diet to help reduce cholesterol
Reducing sodium (i.e. salt) ingestion to keep high blood pressure under control
A routine exercise regimen
Permanently discontinuing cigarette smoking

Medications may include:
Cholesterol-lowering medication
Antiplatelet agents such as aspirin, ticlopidine, or clopidogrel to reduce the risk of blood clots
Glycoprotein inhibitors to reduce the risk of blood clots
Antithrombin agents such as blood-thinners (low-molecular heparin, unfractionated heparin), to reduce the risk of blood clots
Beta-blockers to decrease heart rate and to lower oxygen consumption by the heart
Nitrates such as nitroglycerin to dilate the coronary arteries and improve blood supply to the heart
Calcium-channel blockers to relax the coronary arteries and all systemic arteries and, thus, reduce the workload for the heart
ACE inhibitors, diuretics, or other medications to lower blood pressure
Interventions may include:
Percutaneous Coronary Interventions (PCI's):
Coronary angioplasty
Coronary atherectomy
Catheter-based thrombolysis
Coronary radiation implant
Coronary stenting (placing a tube in the artery to keep it open).

Surgical Interventions:
Coronary artery bypass surgery
Minimally invasive heart surgery
What is the prognosis?

The outcome is variable. Some people can maintain a healthy life by changing diet, stopping smoking, and taking medications as long as they are closely monitored. Others may require more drastic measures, such as surgery. It is necessary to detect CHD early and treat it appropriately.

What can one do to lower the risk of CHD?
Do not smoke
Lower cholesterol levels by eating a low-fat diet
Eat well-balanced meals that include several daily servings of fruits and vegetables
Control blood pressure
Develop a routine exercise regimen. Short, frequent sessions of exercise are preferable to a complete sedentary lifestyle. Walking instead of driving, taking the stairs instead of the elevator, are all measures that most people can incorporate into their busy routines
Keep blood pressure under control
Maintain weight appropriate to the frame and build
Doctor should be consulted about vitamins. Vitamin E has been shown to lower the risk of a heart attack. Vitamin B may also protect against CHD.