Angular velocity and acceleration of the QRS vector in the electrocardiogram of rabbits

The curves of the spatial angular velocity (AV) and of its first derivative (AA) are described for 103 healthy rabbits. After analog-to-digital conversion, the amplified X-, Y- and Z-signals after McFee and Parungao are fed for calculation on a microcomputer. In 41 per cent of the cases the AV curve has two basic waves, in 29 per cent--three, in 21 per cent--one, and in 9 per cent--four, which coincide with the lowest points in the spatial magnitude curve. The AA curve consists of biphasic waves with approximately identical amplitudes of their positive and negative parts. The results are interpreted in connection with the chronotopography of the ventricular depolarization and reorientation of the activation front.