Wireless Powered Embedded Cardiac Pacemaker apart Utilization of Resonant Inductive Coupling.

         In deliberation of great advancement in Implantable Cardiac Pacemaker Technology, notwithstanding  clinical challenges are arrived due to lead and battery complications have addressed a abundant of issues regarding when the pacemaker battery becomes functionally down, pacer integrated batteries, recharge or substitute the appliance battery that are inducing electrical abnormalities addressed as insulation breaks, lead dislodgement and conduction coil fractures which outcome in emerging health risks such as additional cardiac simulation vascular occlusion, erosion of the conduction fibers pacemaker ,infections to the Heart valves , bruising at the pacemaker site, adverse reactions to anesthetics, congestive heart failure, atrial tachycardia and hemorrhaging due to that entire pacemaker unit must be replaced which cause risks identical to those of the original surgery.

         During Implant Procedures besides complications originate involve tissue puncture causing perforation and rupture of heart that is life threatening results in death of patient. To eliminate plenty of the risks associated with lead-based devices we devise a wireless power supply prototype to charge continuously implanted pacemaker by utilizing Inductive power transfer that enables wireless powering of bioelectronic devices without mechanical contact to regulate stimulation intervals with significantly reduced power consumption as wire is extremely uncomfortable because the equipment cannot mobile during Powering or charging.

          A technical solution to these problems is substitute disposable batteries with rechargeable batteries that have witnessed the dramatic emergence medical technologies, such as dealing with congestive heart failure, atrial tachycardia, and Developing monitoring- systems.

          Since rechargeable batteries can supply power for high consumption of energy and current, they can outperform rather than batteries that are applied to implantable pacemakers. In addition to delivering shocks to hearts as disposable batteries serve, rechargeable batteries can also supply energy enough to regulate pacemakers, log data of heart rhythms, and perform other functions such as wireless telemetry, multipointing pacemakers, etc.

https://prezi.com/p/nq84k7xj-pee/?present=1 

 

• A wireless power transfer system is constitute of a power transmitter part and a power receiver part.
• POWER TRANSMITTER PART
• The power transmitter part involve an inverter and primary coils.
• The inverter deliver current to the primary coils which generate magnetic flux that transfers power to the power receiver part.
• POWER RECEIVER PART
• The power receiver part includes a pick-up module and a regulator.
• The pick-up module receives the magnetic flux and generates power.
• The regulator stabilizes the output power by controlling the voltage and current of the pick-up module.
• By EMR transmission of signal takes place from transmitter antenna to the receiver part that is placed incide the pacemaker.
• It includes a jaket that is covered with micro antenna patch in fabricated form.
• By signal generator we provide supply to the transmitter antenna.
• Then receiving antenna receive power from tranmitter antenna and transfer EMR to voltage/current which charges battery of pacemaker.

The wireless pacing system consisted of two physically isolated components as shown in the block diagram (Fig. 1A) and circuit diagram (Fig. 1B and C). The cardiac component was miniaturized by maintaining only the core essentials for delivering a stimulatory pulse to the heart muscle. Therefore, it consisted of no internal control mechanism and simply functioned as a transformation unit, acquiring an AC input from the parallel resonant tank circuit to convert into a DC output for cardiac stimulation (Fig. 1C).

In addition, this pacing module did not encompass any charge storage unit, such as a battery or capacitor. Its activity was entirely controlled remotely via intermittent power delivery from the transmitter at short pulses in the range of 0.1 to 1 ms in duration.

The entirety of the functional components was integrated into the power delivery module, consisting of the logic circuitry, class E power amplifier (PA), and series resonant tank circuit (Fig. 1B).

The quality factor, Q, represents the ability of the resonant circuit to retain energy and is heavily influenced by transmission

frequency, f, as shown in Eq. (1)22:

                                                                                                                            (1)

where L is antenna inductance and R is the effective ohmic losses.

While a higher frequency increases the quality factor, it also leads to an increase in tissue absorption. Moreover, increasing frequency results in decreased efficiency of rectification, thus presenting an additional limitation on the parameter selection. The coupling coefficient, k, is heavily influenced by antenna geometry, as shown in

Eq. (2)24:

                                                                                                                       (2)

where d1 is transmitter antenna diameter, d2 is receiver antenna diameter, and D is distance between antennas.

Antenna geometry also impacts the inductance, which in turn influences the quality factor, as shown in Eq(1). The dimensions of the receiving unit, which will be in contact with the cardiac tissue, must be maintained below a few millimeters to prevent mechanical stresses on the fixation anchor, thus ultimately leading to significant reductions in the coupling coefficient. Together, the quality factor and coupling coefficient determine power transfer efficiency as shown in Eq. (3)25:

                                                                                                                  (3)

where Q1 is the quality factor of the transmitter antenna, Q2 is the quality factor of the receiver antenna,

                                                                                                                     and

                                                                                                      

Notably, despite the pacer size reduction to allow deployment inside the anterior cardiac vein, the subcutaneously positioned transmitting unit in the thorax was able to provide continuous pacing at 60 beats per minute (BPM), 2 V voltage amplitude, and 1 ms pulse width. We established a low power rating of less than 1 mW at a wireless range of > 3 cm with no misalignment, at 2 cm with 45° displacement misalignment, at 2 cm with 45° x-axis angular misalignment, and at 2 cm with 45° y-axis angular misalignment.