The inclusion of the digital system in the Holter recording and analyz
ing systems and the development of micro-computers have multiplied the
possibilities and increased the accuracy of this technique. Analysis
of the ST segment has resulted in a definition of the silent myocardia
l ischaemia syndrome. It has also made it possible to evaluate the imp
ortance of myocardial ischaemia in daily life and to assess the effica
cy of anti-ischaemic treatments.