2.1 Relevance to the driving task
2.1.1 Effects of cardiovascular conditions on driving
Cardiovascular conditions may affect the ability to drive safely due to sudden incapacity such as from a heart attack or arrhythmia. They may also affect concentration and the ability to control a vehicle due to the onset of chest pain, palpitations or breathlessness.
Cardiovascular conditions may also have end- organ effects such as on the brain (stroke), the extremities and the eyes. The relevant chapters should be referred to for advice on the assessment and requirements for these effects (refer to section 6. Neurological conditions and section 10. Vision and eye disorders).
2.1.2 Effects on the heart
A further problem in those who have established ischaemic heart disease is that situations experienced while driving may lead to a faster heart rate and fluctuation in blood pressure, which could trigger angina or even infarction.
2.1.3 Evidence of crash risk
Evidence suggests that people who have severe and even fatal heart attacks while driving may have enough warning to slow down or stop before losing consciousness, since less than half of such attacks result in property damage and injury. However, sometimes no warning occurs or a warning sign is misinterpreted or ignored, and this may result in severe injury or death to the driver and other road users. The quality of available evidence is variable and there are a number of sources of potential bias, so drawing clear conclusions is not always possible (refer to Part A section 1.5. Development and evidence base).