Brain Cardiac Pacemaker

Abstract

The present invention provides monitoring of brain blood circulation in a patient with cardiac pacemaker for the prevention of symptoms associated with pacemaker syndrome and stroke. The monitoring of brain blood flow velocity is performed using a transcranial Doppler ultrasound device synchronized with an implanted cardiac pacemaker, to select the pacing mode that enhances cerebral perfusion in the patient. The system further detects microembolic signals in the cerebral circulation and triggers sonothrombolysis as well as release of thromolytic and neuroprotective agents for clot dissolution.

Claims

1. A system for cardiac pacing that involves monitoring of cerebral blood flow in a patient with cardiac pacemaker.

2. A system of claim 1 wherein the real-time monitoring of cerebral blood flow velocity using a transcranial Doppler ultrasound instrument is functionally integrated into an implanted cardiac pacemaker in a patient.

3. A system of claim 1 wherein the real-time monitoring of cerebral blood flow velocity uses an implanted transcranial Doppler ultrasound probe placed on one or both sides of the temporal bone in a patient with cardiac pacemaker.

4. A system of claim 1 wherein the real-time monitoring of cerebral blood flow velocity is used to select the cardiac pacing mode for best mental performance.

5. A system of claim 1 wherein the real-time monitoring of cerebral blood flow velocity is synchronized with the function of the cardiac pacemaker and is telemetrically connected with the cell phone and a programming computer.

6. A system of claim 1 wherein the real-time monitoring of cerebral blood flow velocity uses an implanted transcranial Doppler ultrasound probe during cardiac pacing to detect the presence of microemboli in the brain circulation.

7. A system of claim 1 wherein the real-time monitoring of cerebral blood flow velocity uses an implanted transcranial Doppler ultrasound probe during cardiac pacing to detect the presence of cerebral microembolic signals and is programmed to administer thrombolytic and neuroprotective medication including through an automatic implanted drug injection pump.

8. A system of claim 1 wherein the real-time monitoring of cerebral blood flow velocity uses implanted ultrasound probes on both sides of the temporal bones synchronized with cardiac pacing to determine the mental state-of-being in a patient and to alter the cardiac pacing mode to enhance cerebral perfusion.

9. A system of claim 1 wherein the real-time monitoring of cerebral blood flow velocity uses implanted ultrasound probes on both sides of the temporal bones synchronized with cardiac pacing to determine the mental state-of-being in a patient with depression, cognitive decline or memory deficits with the aim to alter the cardiac pacing mode to enhance cerebral perfusion.

10. A system of claim 1 wherein the real-time monitoring of cerebral perfusion is indexed using brain electrical potentials that are synchronized with cardiac pacing to determine the mental-state of being in a patient with implanted cardiac pacemaker and to alter the pacing mode to enhance mental performance.

11. A system for cardiac pacing that hermetically contains the circuits for an implanted cardiac pacemaker integrated and synchronized with that of an implanted transcranial Doppler ultrasound device for measurement of cerebral blood flow velocity said system comprising: pulse generator, microprocessor, power supply system, oscillator, timer, memory digital/analog converters, amplifiers, radio-frequency transmitter for telemetric transmission to an external programming computer, with connections to pacing leads or leadless electrodes and implanted transcranial Doppler ultrasound probe.

12. A system of claim 11 wherein the real-time monitoring of cerebral blood flow velocity uses a synchronized but separately implanted transcranial Doppler ultrasound device with probe placed on the temporal bone on the opposite side of a patient with cardiac pacemaker.

13. A system of claim 11 wherein the real-time monitoring of cerebral blood flow velocity is synchronized with cardiac pacing, said method to select the appropriate pacing mode of the implanted cardiac pacemaker using artificial intelligence.

14. A system of claim 11 wherein the real-time monitoring of cerebral blood flow velocity indexed by a transcranial Doppler ultrasound device with probe in a patient with cardiac pacemaker could be made from nano-scale circuit components with lesser need for power supply.

15. A system of claim 11 wherein the real-time monitoring of cerebral blood flow velocity is used to determine microembolic signals, said method to trigger delivery of anticoagulant and neuroprotective agents and sonothrombolysis.

16. A system of claim 11 wherein the real-time monitoring of cerebral blood flow velocity is used to select the cardiac pacing mode that maintains cerebral perfusion for optimal mental performance.

17. A system for non-invasive monitoring of cerebral blood flow velocity using an external transcranial Doppler ultrasound device with external probes, that is telemetrically connected to a cardiac pacemaker implanted in a patient, said system comprising: pulse generator, microprocessor, power supply system, oscillator, timer, memory digital/analog converters, amplifiers, radio-frequency transmitter for telemetric transmission to the cardiac pacemaker and external programming computer.

18. A system of claim 17 wherein the real-time monitoring of cerebral blood flow velocity is used to determine the mental state-of-being by applying artificial intelligence in a patient with an implanted cardiac pacemaker.

19. A system of claim 17 wherein the real-time monitoring of cerebral blood flow velocity uses an external transcranial Doppler ultrasound device and external ultrasound probes placed on the temporal bones, that is telemetrically connected to the cardiac pacemaker implanted in a patient, said method used to select the pacing mode that maintains adequate cerebral perfusion, to detect microembolic signals and to trigger injection of thrombolytic and neuroprotective agents.

20. A system of claim 17 wherein the real-time monitoring of cerebral blood flow velocity uses an external transcranial Doppler ultrasound device and probes placed on the temporal bones, that is telemetrically connected to a cardiac pacemaker implanted in a patient, said method is connected to a cell phone for communication with the patient and doctor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0060] FIG. 1 shows a schematic block diagram that depicts one embodiment of the invention

[0061] FIG. 2 shows the implanted or ‘internal’ device of the invention.

[0062] FIG. 3 shows a brief description of the flowchart for the function of the invention.

[0063] FIG. 4 shows the ‘external’ embodiment of the present invention comprising an external transcranial Doppler ultrasound device with externally placed probes, which is telemetrically connected to a cardiac pacemaker.

[0064] FIG. 5. The schematic diagram of the present invention as ‘external’ transcranial Doppler ultrasound telemetrically connected to a cardiac pacemaker.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0065] One embodiment of the present invention would be illustrated using measurement of cerebral blood flow velocity indexed by an implanted transcranial Doppler ultrasound device with a probe telemetrically connected to a cardiac pacemaker. However, anyone skilled in the art could program the calculations of brain functional indices measured from brain electrical potentials, cerebral blood metabolism, cerebral blood flow or any other biophysiologic parameter indicative of brain cognitive function, without departing from the spirit and scope of the present invention.

[0066] FIG. 1 shows a schematic block diagram that depicts one embodiment of the present invention.

[0067] The device is hermetically contained in a housing 1, that serves as a hybrid device comprising a cardiac pacemaker and an implantable transcranial Doppler ultrasound device. The implantable transcranial Doppler ultrasound has been described in detail according to the teachings by Njemanze P C in U.S. Pat. No. 6,468,219. The present invention generates cardiac pacing pulses, sends and receives ultrasound pulses for the implanted transcranial Doppler ultrasound probe. The present invention hermetically contains 1 electrical components that derive operating power from an internal power supply 2. The power supplies all energy for operations and electrical pulse generation as a source internal to the housing. The pulse generator 3 generates voltage for the cardiac pacemaker operation as well as the ultrasound signals and is operatively connected to the oscillator 4 and timer 5 systems. The timer 5 is operatively coupled to the memory RAM 6, ROM 7, and microprocessor 8, which are hermetically contained within the housing 1 and is communicatively coupled to the oscillator 4 and pulse generator 3. The microprocessor 8 sends signals through digital-to-analog converter 9 and amplifier 10 to connect 11 to the terminals for the electrodes 12 and ultrasound probe 13, as well as receive sensing information through an amplifier 14, and analog-to-digital converter 15. The microprocessor 8 communicates telemetrically through a digital input-output (I/O) interface 16 and antenna 17, across the chest wall 18 to the antenna 19 attached to the external programming computer 20. The microprocessor 8 has the capacity for processing the ultrasound signals required for spectrum analysis that is telemetrically communicated to the programming computer 20 for display of the blood flow waveforms and for further processing and telemetric transmission. The required information could be communicated to the patient via cell phone device through a special software application. The circuit components, leads and leadless electrodes of the cardiac pacemaker could be obtained from Medtronic a company based in Minneapolis, Minn., in the United States. The microprocessor such as that from Pentium Series could be obtained from Intel Company, of San Jose, Calif. Similarly, the circuit components and ultrasound probe for the transcranial Doppler ultrasound device could be obtained from RIMED, a company at the Industrial Park Raanana, Israel. The circuit described could be made from nano-scale components with less need for power supply, while maintaining similar functionality. There are multiple variations of the circuit and software but the illustration given here is only by way of example, and does not limit the scope of the invention.

[0068] FIG. 2 shows the implanted or ‘internal’ device of the invention.

[0069] The device is implanted on the right or left side of the chest wall below the collarbone 21. The leads 22 are inserted into the jugular vein 23 and the leads guided into the correct chambers of the heart, for example, into the right ventricle and right atrium. A third cable 24 for the ultrasound probe is tunneled subcutaneously along the neck to the temporal region of the head to emerge from under the skin flap 25 that has been cut open for insertion of the ultrasound probe 26. The probe is implanted on the temporal bone window (Purkayastha & Sorond, 2012). The cable connects to the ultrasound probe 26 placed directly on the temporal bone 27. The probe emits and receives ultrasound signals focused at a particular depth in a cerebral artery for example, right middle cerebral artery. In some cases, the probe could be implanted on both sides of the temporal bones depending on indication such as when mental state-of-being needs to be monitored. The ultrasound device monitors cerebral blood flow velocity and counts microembolic signals. In some cases, there could be technical constraints such as battery life, for integration of the implanted cardiac pacemaker with the implanted transcranial Doppler ultrasound device and probe. In such cases, a separate implantable transcranial Doppler ultrasound device could be placed on the opposite side of the body with synchronization with the cardiac pacemaker. In another example, a patient with an implanted cardiac pacemaker who develops signs of pacemaker syndrome, could have a transcranial Doppler ultrasound device implanted and synchronized on the opposite side to help alleviate the symptoms.

[0070] FIG. 3 shows a brief description of the flowchart for the function of the invention.

[0071] The flowchart will be illustrated by way of example. The procedure starts 28, with setting from research the predetermined threshold (t) 29 for the values of heart rate (Heart Rate.sub.t), cerebral mean blood flow velocity (CMBFV.sub.t) and microembolic signal count (MES count.sub.t), followed by creation of file records 30 for the parameters Heart Rate, CMBFV and MES count. The values for each parameter Heart Rate, CMBFV and MES count are read 31, if not all have been read, the previous step 31 is repeated, but if all have been read 32, the system proceeds to store the baseline values of the parameters 33 Heart Rate.sub.b, CMBFV.sub.b, MES count.sub.b, and monitors the real-time baseline values of parameters 34 Heart Rate.sub.r, CMBFVr, MES count.sub.r, and compares them to the set threshold of the parameters 35 Heart Rate.sub.t, CMBFV.sub.t, MES count.sub.t, if below the set threshold parameters 36, then the system repeats step 34, if not, the system proceeds to calculate the percentage change of the real-time parameters 37%Heart Rate.sub.r, %CMBFVr, %MES count.sub.r, from baseline values. It updates the changes in real-time from the file of the parameters Heart Rate.sub.r, CMBFV.sub.r, MES count.sub.r 38, and compares the changes to set threshold 39, and if below 40, then it continues to read the real-time values from step 34, conversely, if not, it checks for artifacts 41 using programmed sub-routines for example motion artifacts. If the artifacts are present, it repeats from step 34, but if not, it triggers telemetry to the programming computer 42 to execute programmed sub-routines specific for each patient including HIFU. The programmed sub-routines are chosen based on the clinical presentation of the patient. There are a variety of options, for example, if the system detects microembolic signals above a set threshold, artificial intelligence (AI) deep machine-learning (ML) software routine could be implemented for diagnosis and risk analysis for severe ischemic event, and the system could trigger the doctor's prescribed dosing of an injectable anti-coagulant and/or neuroprotective agent through an implanted pump, and thereafter monitor the effects on improved cerebral blood flow. The AI-ML could detect states of mental performance, sleep pattern of cerebral blood flow velocity, talking and motor-activity so as to recognize these patterns in real-time and distinguishes them from motion artifacts. The Brain Cardiac Pacemaker described below could have two probes, for example, one focused on the left middle cerebral artery (LMCA) and the other focused on the right middle cerebral artery (RMCA), and hence could monitor mental performance as described in the teachings of the U.S. Pat. No. 639,0979B1, (2002), by Njemanze P C, which could be used for the development of the AI-ML sub-routines for each individual patient. Multiple variations are possible depending on the patient's presentation, such that, each sub-routine is individualized according to the doctor's prescription.

[0072] FIG. 4 shows the ‘external’ embodiment of the present invention comprising an external transcranial Doppler ultrasound device with externally placed probes, which is telemetrically connected to a cardiac pacemaker.

[0073] The design of the external unit of the present invention eliminates the need for revision of functioning implanted cardiac pacemakers. Rather the pacing mode of the cardiac pacemaker could be adjusted based on the mental state-of-being of the patient after evaluation with the external unit of the present invention. A choice could be made on the best mode of pacing to optimize mental performance assessed clinically or according to the teachings of U.S. Pat. No. 6,390,979 to Njemanze, 2002.

[0074] In some patients with cardiac pacemakers, the doctor may choose to synchronize the function with an externally mounted transcranial Doppler ultrasound device 43 with ultrasound head probes 44 placed on the temporal bone mounted on a probe hanger 45, from both sides of the head. The transcranial Doppler ultrasound device synchronizes blood flow velocity measurements with cardiac pacing. The transcranial Doppler ultrasound device is telemetrically communicating with the microprocessor of the cardiac pacemaker to achieve the same functionality as described above in FIG. 3. The design of the external transcranial probe for long-time monitoring could be done in a number of ways for example, as described by in U.S. Pat. No 6,547,737B2 by Njemanze P C. In the clinical setting, the external transcranial Doppler ultrasound is used to evaluate if the symptoms of the patient could be relieved by monitoring the cerebral blood flow velocity and synchronizing the function to different modes of cardiac pacing. The external Brain Cardiac Pacemaker is used for development of AI-ML sub-routines for each patient in the training phase. Once the clinical goals are achieved for the patient, the Brain Cardiac Pacemaker with the permanent telemetric transcranial Doppler ultrasound device with probe could be implanted.

[0075] FIG. 5. The schematic diagram of the present invention as ‘external’ transcranial Doppler ultrasound telemetrically connected to an implanted cardiac pacemaker.

[0076] FIG. 5. shows the device that has the form of a cellular telephone device 46 with the usual features of an LCD display 47, an input keypad 48, a loudspeaker 49 and a microphone 50. An aerial receiver 51 for radio frequency transmission and reception of signals in addition to locating the user's position using global positioning system (GPS). The device has means for telemetric connection including radio frequency, Bluetooth and others. The present invention has a headset connected to an adapter terminal 52 through a cable 53 to the headset with left 54 and right 55 sides placed on the left temporal and right temporal bones, respectively. Each side of the headset has an ear piece on the right 56 and left 57 for audio communication to the patient. There are transcranial Doppler ultrasound probes on the right 58 and left 59 temporal bones contained in the probe housing and focused for measurement of cerebral blood flow velocities in intracranial arteries. The synchronous bilateral probes have artificial intelligent (AI) automated angulation for insonation of cerebral arteries according to the teachings of Njemanze in U.S. Pat. No. 6,547,737. If the patient speaks, the system monitors the audio signals through a microphone 60. The present invention was designed as a portable device to monitor cerebral blood flow velocity which is telemetrically synchronized with a cardiac pacemaker. The cellular phone packaging parts could be obtained from Nokia a company based in Espoo, Finland. The microprocessor such as that from Pentium Series could be obtained from Intel Company, of San Jose, Calif. by way of example. This present invention is a composite device comprising function of a microcomputer for the transcranial Doppler ultrasound, a cellular phone telemetrically connected to the functionality of an implanted cardiac pacemaker. It could be applied in clinical situations when cerebral blood flow velocity needs to be monitored and telemetrically synchronized to another biophysiologic parameter.