[The clinical value of Holter ECG recording].

The Holter ECG is a well established clinical tool to document intermittent arrhythmias. The main indications are palpitations and syncope. However, the occurrence of these events during 24 h recording is very rare. So, it is often a matter of definition, what findings can speculatively "explain" a syncope. Therefore, an event recorder is often more successful. In addition, in patients with organic heart disease and reduced left ventricular function invasive electrophysiologic testing may be more appropriate. In these cases prophylactic implantation of an ICD may be indicated to prevent sudden death. So, in many instances the clinical value of Holter recording is overestimated.