Definition : Electrocardiographs designed for recording a graphical representation of the sequence of changes in magnitude and direction (i.e., vector representation) of the electric potentials in one or more complete cardiac cycles (i.e., a vectorcardiogram). These instruments record cardiac events in three orthogonal planes (i.e., X, Y, Z) and may be capable of recording: (1) isolated cardiac contractions (i.e., beat-to-beat recording); (2) continuous (timed) recording of events; and (3) separate graphics of the ECG signals for each plane. Vectorcardiographs typically consist of dedicated electrocardiographs including appropriate detachable electrodes, computing capabilities, and software, as well as printers or graphical plotters that can display the vector cardiogram from the electrocardiographic signals. Instruments based on the transmission of signals to an oscilloscope for graphic representation of the vectorcardiogram of isolated cardiac contractions (typically obtained as a photo of the loop displayed on the oscilloscope screen) may be also used. Vectorcardiographs are used to diagnose abnormal and pathologic conditions of the heart; instruments providing continuous recording may be used in the detection and/or monitoring of arrhythmias. Some multichannel interpretative electrocardiographs may provide a vectorcardiogram using appropriate computer algorithms.
Entry Terms : "Cardiographs, Vector" , "Electrocardiographs, Vector" , "Vector Electrocardiographs"
UMDC code : 14345