Late potential (LP) analysis in the signal-averaged ECG is a useful clinical tool in the detection of patients at risk after myocardial infarction (Mi). The presence of abnormal LP activity has been correlated with inducible ventricular tachycardia (VT) at programmed electrical stimulation in post-MI patients. A novel and reliable approach which quantifies the chaotic-like nature of LP activity in the time domain is presented here. By establishing the basin of attraction of the LP attractor in the microvoltage, 3-dimensional space, and then computing the fractal dimension (delta) of the attractor's trajectory, the strangeness of the dynamical behaviour of late potentials was quantified. Thus, the parameter delta provides an index of the chaotic behaviour of the terminal dynamic of the ventricular depolarization process which could reflect the patient's susceptibility to VT. In order to study this relationship, the parameter delta was evaluated in a control group of 30 healthy subjects (Group 1) and in 30 post-MI patients which were VT inducibles as a result of programmed electrical stimulation (Group 2). The results of the study indicated that the value of delta was significantly higher (a more chaotic attractor) in Group 2 than in Group 1 (p < 0.001). Thus, these results suggest a close correlation between the chaotic nature of late potentials and the subject's susceptibility to enter into a catastrophic arrhythmia such as VT. A value of delta > 1.3 may be considered as the criterion for discriminating post-MI patients that are at risk or as having chaotic LP activity.
|Title of host publication||Unknown Host Publication|
|Editors||M Cerrolaza, D Jugo, CA Brebbia|
|Place of Publication||ASHURST LODGE, SOUTHAMPTON, HANTS, ENGLAND S04 2AA|
|Publisher||Computational Mechanics Publications|
|Number of pages||10|
|Publication status||Published - 15 Dec 1996|
|Event||International Conference on Simulation Modelling in Bioengineering, BIOSIM 96 - Merida, Venezuela|
Duration: 15 Dec 1996 → …
|Conference||International Conference on Simulation Modelling in Bioengineering, BIOSIM 96|
|Period||15/12/96 → …|
- Computational methods
- Computer simulation
- Patient monitoring
- Time domain analysis
- Catastrophic arrhythmia
- Late potential (LP) analysis
- Myocardial infarction (MI)
- Ventricular tachycardia (VT)
- high-resolution ECG.
Escalona, OJ. (1996). Incidence of chaotic behaviour of ventricular late potentials on patient's susceptibility to a catastrophic arrhythmia. In M. Cerrolaza, D. Jugo, & CA. Brebbia (Eds.), Unknown Host Publication (Vol. 1, pp. 281-290). Computational Mechanics Publications.