ANGINA & HEART ATTACK (MYOCARDIAL INFARCTION)
Dr. Richard Mansfield
BSc (Hons) MB ChB MD FRCP FESC
CONSULTANT CARDIOLOGIST
Note: I am happy to answer general questions regarding the content of this website, but I cannot give clinical advice. Such requests will not be answered.
Angina is a discomfort in the chest typically behind the breastbone that spreads to the arms (mostly the left arm) as well as the throat, jaw and neck. It may also spread down towards the stomach. It is typically provoked by exercise and may be brought on by walking in a cold wind or after a meal. It may also be brought on by stress. It is usually relieved by rest after a period of minutes.
Angina is most commonly caused by narrowed coronary arteries. The process by which arteries narrow is known as atherosclerosis where cholesterol build up gradually obstructs the flow of blood down the artery. This is otherwise known by the term coronary artery disease.
Coronary artery disease is associated with a number of risk factors including
1. Cigarette smoking
2. Diabetes
3. High cholesterol
4. High blood pressure (Hypertension)
5. A positive family history of angina or Heart Attack (Myocardial Infarction)
Investigation of patients with possible angina may include blood tests to look for evidence of anaemia, high cholesterol or diabetes. An ECG will be recorded and patients may have an exercise treadmill test. Alternative investigations include a myocardial perfusion scan or dobutamine stress echocardiogram. If any of these tests should suggest a problem with the heart arteries then it is likely that a coronary angiogram will be recommended.
Patients with coronary artery disease will be started on a number of drugs including aspirin (to prevent the blood being too sticky) and a statin (to lower cholesterol). It is usual to be prescribed a GTN (nitrate) spray or tablet to take under the tongue if experiencing angina. Depending on the level of symptoms a number of anti-anginal tablets may be prescribed. Beta-blockers (Atenolol, Bisoprolol) are often used and work by slowing the heart rate. Other tablets including calcium channel antagonists (Diltiazem, Amlodipine), Nitrates (Isosorbide Mononitrate) and Nicorandil, aim to relax the coronary arteries. Newer medications include Ivabradine (which works like a beta-blocker) and Ranolazine. Another group of tablets called ACE inhibitors are often prescribed as they help to protect the heart and the heart arteries.
Some patients will be treated with tablets alone but depending on the results of an angiogram and possibly some additional tests may have Percutaneous Coronary Intervention (PCI) or Coronary Artery Bypass Surgery (CABG).
A heart attack (myocardial infarction) occurs when a narrowed artery is blocked by a blood clot. The symptoms are much more severe than a typical angina attack. The chest pain/discomfort is more prolonged - generally lasting for more than 15 minutes and it is very usual for patients to feel nauseated and they may vomit. They may be breathless. Observers may note them to be sweaty and pale or cold to the touch.
A new term of - Acute Coronary Syndrome - has been adopted to refer to all patients with threatened or proven heart attack or those with unstable angina.
Traditionally clot-dissolving drugs were used to re-open the artery (thrombolysis) and were given through a vein. It is more usual now to try and open the artery with a procedure known as Primary Percutaneous Coronary Intervention.
On discharge from hospital all patients who have suffered a heart attack will be on some medication to reduce their cardiac risk. This will often include drugs to prevent the blood from being too sticky (aspirin and clopidogrel), a tablet to lower cholesterol (statin), fish oil capsules (omacor) a tablet to protect the arteries and strengthen the heart (ACE inhibitor) and a beta-blocker. Almost all patients will undergo a period of cardiac rehabilitation.