The pathomechanism of the condition is irrelevant. Among ischaemic diseases, a distinction is made between coronary artery disease, which includes myocardial ischaemic states associated with lesions in the coronary arteries.

Coronary artery disease can have an acute or chronic form. In the acute form, a distinction is made between ST-elevation and non-ST-elevation coronary syndromes on the basis of the initial ECG. On the basis of clinical presentation, biochemical markers of myocardial damage and ECG imaging, a distinction is made between unstable angina, non-ST-elevation myocardial infarction, ST-elevation myocardial infarction, unspecified myocardial infarction and sudden cardiac death. Based on the evolution of the ECG image, non-Q-wave or Q-wave myocardial infarction is defined.

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Fresh my ocardialinfarction is diagnosed when there is evidence of cardiomyocyte necrosis in a situation corresponding to acute myocardial ischaemia.

In this case, infarction is diagnosed in any of the situations mentioned:

• an increase and/or decrease in cardiac biomarker values with at least one value above the 99th centile of the upper limit of the range and at least one of the following conditions: subjective symptoms of myocardial ischaemia new ST-segment and Q-wave changes or new left bundle branch block the occurrence of pathological Q-waves on ECG imaging the finding of a new picture of non-viable myocardium or a new abnormality of segmental mobility of the heart wall the detection of a coronary artery thrombus;
• cardiac death;
• myocardial infarction associated with stent thrombosis;
• myocardial infarction associated with percutaneous coronary intervention;
• myocardial infarction associated with coronary artery bypass grafting.

Myocardial infarctionis diagnosed when pathological Q-waves are present on ECG that cannot be explained by any other cause, when a non-viable myocardial area is found, or when features of past myocardial infarction are present on anatomopathological examination.