I1. Ischaemic Heart Disease

Ischemic Heart Disease

This is the disease state where the atherosclerotic process has reached a level that has produced reduced blood flow to the heart muscle, presenting as one of: an acute coronary syndrome (heart attack / unstable angina), exertional angina, heart failure, a finding on a screening stress test or worst, as sudden death.

What is angina?

Angina (literally “choking” in Greek) is a discomfort that comes from the heart muscle when the blood supply it requires cannot be provided and there is a build up of noxious agents in the heart muscle which causes symptoms. Angina is a clinical diagnosis, in other words based on your doctor’s interpretation of what you tell them.

Typical angina

Typical angina is not necessarily a pain, but more a discomfort, sometimes intense, in the chest, often in the middle, that is tight / constricting / pressure like. It can spread to the back, the neck including the jaw and typically the left shoulder or arm / wrist, and sometimes the right arm. Often it is associated with sweating / breathlessness. Unless unstable it is brought on with exercise, especially after eating, and settles with rest. It usually only lasts a few minutes and symptoms that last for over 30 minutes are more likely to be unstable angina. Angina can occur with emotional upset, lying down in bed and in severe disease occurs at rest / night, but only lasts 5-10 minutes.

This can occur suddenly as in an acute coronary syndrome (unstable angina); in the face of a stable fixed obstruction when the heart has to work harder with exercise, emotion or even at rest when a narrowing is tight enough (chronic stable angina); when another medical condition occurs such as infection or anaemia (secondary angina); or when the width a blood vessel varies because of altered muscle tone in the lining of the vessel (coronary spasm) – the vessels are more irritable overnight, hence angina often occurs at night if the setting is right.

Atypical angina

Atypical angina is the term used to describe symptoms that

  • occur with a typical pattern for angina (usually exertional), but not based around the chest, for example just in the left arm or the jaw.
  • Are not typical of angina, but shown to be associated with evidence of reduced blood flow to the heart muscle on an ECG or stress test
  • In retrospect when blood tests have shown evidence of heart muscle injury with unusual symptoms – the classic example here is the bad attack of indigestion which lasts 2-3 hours and does not settle with anti-indigestion therapy

Atypical chest pain

This is a phrase that generally should be avoided, but is usually being used to describe discomfort in the chest that does not have positive features to suggest angina, with no objective evidence to suggest a problem with the heart. Prior to using this label your doctor will have excluded other causes of chest pain, which can come from the lung, the oesophagus, the stomach, the musculoskeletal system and even the gallbladder. A better phrase is chest pain of no obvious source, or chest pain not suggestive of myocardial ischaemia, if only cardiac investigations have been performed.