Impulsive control as a novel defibrillator algorithm using coupled Van der Pol oscillators

Abstract

This paper proposes a strategy for improving a patient-centric implantable cardioverter defibrillator (ICD) for real time implementation, to deal with heart related ailments like ventricular flutter and sinus bradycardia. A patient-centric dynamic model of heart rhythm is generated similar to the real Electrocardiogram (ECG) signals using three coupled Van der Pol (VdP) oscillators. These oscillators represent the dynamics of three nodes viz. the Sino-Atrial (SA) node, Atrio-Ventricular (AV) node and the His-Purkinje (HP) complex. The coupled VdP oscillator model based closed loop impulsive control methodology is then developed which starts functioning when there is aberrant behavior due to the diseased condition in the electrical activities generated by the different nodes of the heart. An embedded control system can be augmented to the ICD devices with the proposed control methodology having a patient-centric and disease-specific characteristic of the control law. The impulsive control strategy is specifically useful for such purposes over the continuous control techniques, as it helps in conserving the battery power of such devices and enables a longer lifetime of the ICD device. Numerical simulations are shown to illustrate the practicality of the proposed approach.