3D CARDIOGRAPHIC DISPLAY FEATURES
A NEW 3D CARDIOGRAPHIC DISPLAY
A new three-dimensional cardiographic display has been conceived for the display of the X, Y and Z-axis outputs from a modified Frank configuration of electrodes. For each two millisecond of sampled data from a Electrocardiograph (ECG) digitally recorded signal a triangular surface is plotted from the origin to two points in 3D space as related to the X, Y and Z information for the beginning and end of that section of the QRS signal. The X, Y, and Z information can also be derived from other electrode configurations, such as the well-known 12-lead system, which is used extensively in the analysis of ECG data. The purpose of this new display is to make it easier and more accurate for a doctor or medical technician to recognize the presence of heart malfunctions and the specific type of malady that exists. The new display also provides the integration of 12 lead, and Vectorcardiograph information on the same display that can be used to further enhance the diagnosis of heart disease:
© Copyright 1999/2000 Charles Olson
U.S. Patent 5803084 and International Patents Pending
An example of this display for a normal heart is shown in figure 1, showing a 3D vectorcariographic display with color coding for the time of occurrence of each 20 ms sector, and 2 ms segments within this sector.
1. The presentation of the surface formed by the heart vectors during the P-wave, the QRS, and The T-wave in a 3D projection format so that the eye perceives a 3 dimensional display of the vectors in relation to the X, Y and Z coordinates of the body. The display is scaled to provide a reference in mv.
2. The projection of the 3D heart vectors into 3 planes - the frontal, the transverse and the sagittal. These displays have been investigated many years ago (known as vectorcardiography) and provide a very useful method of diagnosis by themselves. The addition of these to the vector display further enhances the interpretation of the vector presentation.
3. The color coding of the time of occurrence of the events in the P-wave, the QRS cycle, the ST offset, and the T-wave to clearly show their inter-relationship and timing.
4. Adding a calibrated display of the magnitude of the vector (Magnitude = square-root (X^2 + Y^2 + Z^2)) makes it easier to evaluate hypertrophy.
5. The delta change in Magnitude from one vector to the next is an indication of the continuity of heart muscle cell activation and an additional indicator of disease.
6. The delta change in the angle of the heart vectors over the same time period as a further indicator of muscle cell activation and smoothness of transition of the depolarization of cells over the myocardium.
7. The vector display may be expanded in steps to allow the more detailed examination of any portion of the vector sequence, to be able to observe in detail the size and direction taken by these signals as a function of time.
8. The vector display position may be shifted in steps both horizontally and vertically from its present location.
9. The vector display may be rotated about the vertical axis - 360 degrees, in steps and rotated about the horizontal axis in angular steps.
10. At the end of the QRS complex and the beginning of the T-wave a bright red vector is drawn from the origin to this point. In the event of a ST voltage offset this red vector shows the magnitude and direction of this offset. In the case of a new infarct (a recent heart attack), ischemic tissue will produce an offset. The vector direction of this offset will point towards the injured tissue.