[Long-term electrocardiogram]

The review deals with the technical and clinical advances achieved in the field of long-term electrocardiography over the past decades, and outlines possible future developments. The technological background is reviewed from the initial conception by Dr Norman J Holter up to the modern loop and implantable recorders. The contemporary clinical applicability is considered including arrhythmia monitoring, tracking the morphological electrocardiographic changes with particular attention to ischaemia monitoring, and high-precision electrocardiographic measurements related to the assessment of drug-induced myocardial repolarisation changes. The section on future outlook discusses the possibility of using long-term electrocardiograms for identification of patients at increased risk of sudden arrhythmic death that might be preventable by prophylactic use of implantable defibrillators.