Ischaemic heart disease (IHD) and stroke are the most frequently occurring among cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of death and hospitalisation in both sexes in nearly all EU countries. More than 2 million people die every year in the EU-27 countries, accounting for nearly half of all deaths (45% of deaths in women and 38% deaths in men; see Death by main cause). From the total group of cardiovascular diseases, ischaemic heart disease and stroke are the most frequent. Both are of an atherosclerotic origin. This EUphact deals exclusively with IHD. The topic of stroke will be discussed in a separate EUphact.

Ischaemic heart disease

According to the International Classification of Diseases, as shown in the table below, IHD includes acute myocardial infarction (AMI), commonly known as heart attack, acute coronary syndrome (ACS), angina pectoris and other forms of coronary heart disease (CHD). IHD is caused by atherosclerosis, i.e. the accumulation of plaque on the walls of the coronary arteries. This causes an oxygen shortage (ischaemia) in the heart muscle. Chest pain, biochemical markers of myocardial necrosis and ECG findings are important for diagnosis.

Table 1: Division of Ischaemic Heart Disease according to the International Classification of Diseases (ICD; source; EUROCISS, 2003)

AMI/ACS: sudden and complete closure of a coronary artery

An AMI/ACS occurs when a blood clot suddenly blocks a coronary artery. Through this blockage a part of the heart muscle no longer receives any oxygen and dies. At the site of the infarction a scar develops (old myocardial infarction), which eventually turns into connective tissue leading to a loss of function in the heart muscle. Major complications will result in heart failure. An AMI/ACS can be associated with serious cardiac arrhythmia and can lead to death.

The clinical and cardiac marker manifestations are determined by the volume of heart muscle affected and the severity of ischaemia. Despite the similarities in disease mechanism, the time course and severity of cardiac complications vary substantially across the spectrum of AMI/ACS. Similarly, treatment patterns differ. AMI/ACS should be classified as either:

• ACS in the form of unstable angina but without myocardial injury; or
• ACS with angina and a limited myocardial injury (cell death); or
• ACS with a more substantial myocardial injury.

Angina pectoris

Angina pectoris, literally pain in the chest, is almost always caused by one or more constrictions in the coronary arteries, leading to a temporary shortage in the blood flow and available oxygen in part of the heart muscle. This oxygen shortage is often associated with physical effort or psychological stress. Under these circumstances, heart rate increases and blood pressure rises, which results in the heart muscle needing more oxygen than the constricted blood vessel can supply. The symptoms of angina pectoris disappear shortly after the physical exertion has ended. Angina pectoris causes a typical oppressive, pressing chest pain.

Angina pectoris can be separated into stable and unstable angina pectoris. There are differences in symptoms, in the pathophysiological state and also in the prognosis. In stable angina pectoris the symptoms do not progress in intensity over time. They usually occur in response to provocative influences, such as physical exertion or a change from warmer to colder temperatures. Pathologically, an atherosclerotic constriction is present in the coronary arteries, but in the case of chronic angina the plaques are stable. Unstable angina pectoris is diagnosed where the same symptoms are newly occurring or increasing in relatively short time, without preceding provocative influences. Pathologically, it can be associated with a clot developing in the coronary artery where an atherosclerotic lesion or plaque has formed.

ECG specifies location and severity of acute events

An electrocardiogram (ECG) provides important information about the location and seriousness of the vessel blockage in patients suffering from an acute AMI/ACS. In the case of stable angina pectoris, abnormalities are only visible on the ECG when the patient is actually experiencing the symptoms. Therefore patients with (suspected) angina pectoris are subjected to an examination, such as a treadmill test, in which their heart is put under strain. A possible oxygen shortage can then be identified.

The course of disease depends on various factors

The prognosis of patients with IHD is dependent on the seriousness of the atherosclerotic abnormalities of the heart and other possible affected organs (brain, kidney, large blood vessels), the remaining functions of the heart and the presence and scope of the known risk factors for atherosclerosis.