Definition

The Holter is a recording technique of cardiac activity of a subject for 24 or 48 hours, to continue its activities normally, without bed rest or hospitalization. This review analysis on 24 or 48 hours, the heart rate of an individual to detect a possible cardiovascular pathology. Registration, which is done on magnetic tape, detects an anomaly in the area of myocardial where arise the influx evoking the contractions of the heart, i.e. the sinus node. The Holter is particularly indicated in certain cardiac pathologies, but also in prevention, with individuals of a pacemaker should be monitored. Its use is also in the monitoring of cardiac arrhythmias (irregular heart rate as premature beats among others).

Medical technique

Electrocardiogram (ECG) is an essential contribution in cardiology. Indeed, it allows to detect and diagnose the different types of heart rate and rhythm disorders. Electrocardiogram saves the heart electrical forces. Whenever the bat heart i.e. at each repetition of the cardiac cycle, approximately every second, occur a series of electrical pulses that reflect precisely the action of the heart pump. These pulses can be recorded using electrodes that are placed on the body surface. Cardiac activity results in the appearance of typical wave (QRS) that can be instantly see on a screen of control and that can be recorded on a strip of graph paper. This band of graph paper is then investigated later by one or several cardiologists. Indispensable tool, also called portable ECG Holter, the name of its inventor in 1961, called also ambulatory electrocardiogram, is recording electrodes are fixed on the chest and connected a small box containing a recording device. Specifically the Holter comes in the form of a recorder the size of a Walkman cassette. The electrodes are glued on the chest of the patient thus enabling the device capture beats and electrical activities of the heart and transmit them to the recorder placed around the waist. The slow progress of the magnetic tape allows the registration of any change in heart rate. The cardiologist will then scroll this band at accelerated speed. This recording contains approximately 100,000 cardiac complex (a complex corresponding to a heartbeat). Any changes of the registration must be correlated with the daily activities of the patient. Some events of the day (such as a meal, some activities,…) are likely to alter the heart rate (emotions, joys, efforts, etc.). The patient should note this on a book to assist the practitioner in his diagnosis. Back in cardiology consultation one to two days later, the cardiologist will have a record that covers a whole day of activity of the heart. Holter system is thus used to diagnose heart rhythm disorders that occur in specific circumstances or unexpected manner. A report is presented to the patient and the attending physician. It includes the activities and the symptoms you describe to the doctor and that you have written during hours that correspond. The physician or cardiologist can thus perform reconciliations between the symptoms you describe, and with the Holter ECG recording. In some patients the symptoms do not occur during the period which has been conducting the Holter. In this case the doctor may then consider using a device to record electrocardiography by telephone. It will be used at the time where the symptoms appear. Can be for example of palpitations, extrasystoles, pain etc. This will lead to better guide the diagnosis.