A definition of myocardial infarction, applicable for both clinical practice and research, must be globally accepted. The aim of the Global Myocardial Infarction Task Force, formed by the ESC, AHA, ACC, WHF and WHO, is to propose such a definition. Although the final version of the document is not yet available, diagnostic criteria similar to those proposed by the ESC/ACC Task Force in 2000, will be used (1).
Distinction between myocardial necrosis and infarction
Dr Joseph Alpert (Tucson,US), co-chair of the current Task Force, highlighted the most important changes in MI diagnosis that will be introduced in the new document. There will be a distinction between myocardial necrosis and infarction. Clinical classification of different types of myocardial infarction will be proposed.
Detection of elevated values of cardiac biomarkers above the 99th percentile of normal, together with ischaemic symptoms, ECG changes indicative of new ischaemia, development of pathological Q waves or imaging evidence of new loss of viable myocardium, will be required for the diagnosis of acute myocardial infarction. Several other criteria will be also proposed.
Definition of myocardial infarction related to coronary interventions, both surgical and percutaneous, is still under debate.
Impact of the new MI definition in countries with economy in transition
Dr George Mensah (Altanta, US) discussed the impact of the new MI definition in countries with economy in transition. He said that there are important variations between countries in economics, policies, public health infrastructures, as well as in advancement in science and technology. Therefore global implementation of the guidelines that require some investment in technology may be very difficult. Dr. Mensah also remarked that the new definition will have an impact on assessment of incidence and dynamics of CVD in different geographical areas. He stated, however, that the new definition is a necessary change, based on recent advances in science and practice.
Potential consequences of the new definition for the patients
Prof. Philip Poole-Wilson (London,UK) reviewed potential consequences of the new definition for the patients. He pointed out that patients are unlikely to be directly interested in the changes in definition, and are rather concerned about pain, survival, and future – including continuation of work and insurability. The two latter aspects can be indeed affected by the new definition of MI. He also said that about 80% of infarcts occur in low income countries. Therefore, the UN Millenium Goals should include CVD, in order to streamline economical aid to these areas. Prof. Poole-Wilson indicated that the new MI definition will reflect a global consensus, but will have no impact on pathology, and hence should not influence such areas as employment or insurability. A proper educational campaign for patients, media and politicians is therefore desirable.
Implementation difficulties
Finally, Dr Shanti Mendis (Geneva, CH) addressed difficulties in the implementation of new diagnostic criteria in different parts of the world. She said that in many countries there is only a limited access to technology, and for a majority of people primary medical care has to be provided without any technical aid. Guidance on minimum facilities for primary healthcare should be provided, which will facilitate the implementation of diagnostic criteria outlined in the document.