US-12616831-B2 - Transvascular nerve stimulation apparatus and methods

Abstract

The invention, in one aspect, relates to an intravascular electrode system. The system comprises one or more electrodes supported on an elongated resiliently flexible support member, and the support member may be used to introduce the electrodes into a blood vessel. As the support member is introduced into the blood vessel the support member bends to follow the path of the blood vessel.

Inventors

• Joaquin Andres Hoffer
• Marc-Andre Nolette
• Viral Thakkar
• Bao Dung Tran

Assignees

• LUNGPACER MEDICAL INC.

Dates

Publication Date

20260505

Application Date

20220512

Claims (17)

1. 1 . A nerve stimulation system, comprising: a catheter including at least one lumen configured to remove a fluid from a patient or deliver a fluid to the patient; a plurality of first electrodes supported by the catheter, wherein at least one first electrode is configured for stimulating a right phrenic nerve; and a plurality of second electrodes supported by the catheter, wherein at least one second electrode is configured for stimulating a left phrenic nerve; wherein a first length of the catheter is more flexible than a second length of the catheter; and wherein at least one electrode of the plurality of first electrodes, or the plurality of second electrodes, is configured to monitor bioelectrical activity of the patient, and monitoring the bioelectrical activity of the patient includes ECG monitoring.
2. 2 . The system of claim 1 , further comprising a control unit configured to determine a first combination of first electrodes that most effectively stimulates the right phrenic nerve and a second combination of second electrodes that most effectively stimulates the left phrenic nerve.
3. 3 . The system of claim 2 , wherein a circumferential orientation of the first combination is different than a circumferential orientation of the second combination.
4. 4 . The system of claim 1 , further comprising a control unit configured to monitor stimulation parameters and results of stimulation.
5. 5 . The system of claim 4 , further comprising a sensor configured to acquire positional data and relay the positional data to the control unit.
6. 6 . The system of claim 1 , wherein the first length is closer to a distal end of the catheter than the second length, the plurality of first electrodes are supported by the first length of the catheter, and the plurality of second electrodes are supported by the second length of the catheter.
7. 7 . A nerve stimulation system, comprising: a catheter including at least one lumen configured to remove a fluid from a patient or deliver a fluid to the patient; an electrode assembly supported by the catheter and including a plurality of electrodes, wherein a portion of the plurality of electrodes is configured for stimulating a phrenic nerve; and a control unit configured to: measure a first amount of current required to stimulate the phrenic nerve from a first combination of electrodes; measure a second amount of current required to stimulate the phrenic nerve from a second combination of electrodes; and based on the first and second amounts, determine a combination of electrodes that most effectively stimulates the phrenic nerve.
8. 8 . The system of claim 7 , wherein the control unit is further configured to monitor stimulation parameters and results of stimulation.
9. 9 . The system of claim 7 , wherein the system further comprises a sensor configured to acquire positional data and relay the positional data to the control unit.
10. 10 . The system of claim 7 , wherein the electrode assembly includes a metal ribbon and an insulative layer.
11. 11 . The system of claim 10 , wherein the insulative layer is a first insulative layer, and a portion of the metal ribbon is disposed between the first insulative layer and a second insulative layer.
12. 12 . The system of claim 10 , wherein an aperture of the insulative layer includes metal, and the metal connects the metal ribbon to at least one electrode of the plurality of electrodes.
13. 13 . The system of claim 10 , wherein the insulative layer comprises Teflon™, polyurethane, or silicone.
14. 14 . The system of claim 7 , wherein the electrode assembly further comprises a thermistor, an oxygen sensor, and/or a CO 2 sensor.
15. 15 . A nerve stimulation system, comprising: a catheter; a plurality of first electrodes supported by the catheter, wherein at least one first electrode is configured for stimulating a right phrenic nerve; a plurality of second electrodes supported by the catheter, wherein at least one second electrode is configured for stimulating a left phrenic nerve; and a control unit configured to determine a first combination of first electrodes that most effectively stimulates the right phrenic nerve and a second combination of second electrodes that most effectively stimulates the left phrenic nerve; wherein a circumferential orientation of the first combination is different than a circumferential orientation of the second combination; wherein at least one electrode of the plurality of first electrodes, or the plurality of second electrodes, is configured to monitor bioelectrical activity of the patient; and wherein the plurality of first electrodes, the plurality of second electrodes, or both, includes a plethysmography electrode.
16. 16 . The system of claim 15 , wherein monitoring the bioelectrical activity of the patient includes ECG monitoring.
17. 17 . The system of claim 15 , wherein the at least one electrode is connected to a metal ribbon disposed between a top insulative layer and a bottom insulative layer.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 16/676,983, filed Nov. 7, 2019, which is a continuation of U.S. patent application Ser. No. 14/383,285, filed Sep. 5, 2014 (now U.S. Pat. No. 10,512,772, issued on Dec. 24, 2019), which is a 371 national stage application of PCT Patent Application No. PCT/CA2013/050159, filed Mar. 4, 2013, which claims priority from U.S. Provisional Patent Application No. 61/606,899, filed Mar. 5, 2012. The entirety of each of the above applications is incorporated herein by reference. TECHNICAL FIELD The invention relates to neurophysiology and in particular to apparatus and methods for stimulating nerves through the walls of blood vessels. Non-limiting embodiments include nerve stimulation apparatus, electrode structures, electrodes and related methods. BACKGROUND Nerve stimulation can be applied in the treatment of a range of conditions. Nerve stimulation may be applied to control muscle activity or to generate sensory signals. Nerves may be stimulated by surgically implanting electrodes in or near the nerves and driving the electrodes from an implanted or external source of electricity. The phrenic nerves normally carry signals that cause the contractions of the diaphragm that are necessary for breathing. Various conditions can prevent appropriate signals from being delivered to the phrenic nerves. These include: chronic or acute injury to the spinal cord or brain stem;Amyotrophic Lateral Sclerosis (ALS);disease affecting the spinal cord or brain stem; and,decreased day or night ventilatory drive (e.g. central sleep apnea, Ondine's curse). These conditions affect a significant number of people. Mechanical ventilation (MV) may be used to help patients breathe. Some patients require chronic mechanical ventilation and many more patients require temporary mechanical ventilation. Mechanical ventilation can be lifesaving but has a range of significant problems and/or side effects. Mechanical ventilation: tends to provide insufficient venting of the lungs. This can lead to accumulation of fluid in the lungs and susceptibility to infection and pneumonia.requires apparatus that is not readily portable.can adversely affect venous return because the lungs are positively pressurized.interferes with eating and speaking.requires costly maintenance and disposables.tends to cause positive pressure ventilator induced lung injury (VILI) and ventilator associated pneumonia (VAP). A patient on mechanical ventilation is tied to a ventilator, and does not breathe independently. This can lead to atrophy of the diaphragm muscle (ventilator induced diaphragmatic dysfunction; VIDD) and an overall decline in well being. Muscle atrophy can occur surprisingly rapidly and can be a serious problem. In patients on mechanical ventilation, the central respiratory drive of the diaphragm is suppressed. The inactivity of the diaphragm muscle causes rapid disuse atrophy. According to a published study (Levine et al., New England Journal of Medicine, 358: 1327-1335, 2008), the diaphragm muscle could shrink by 52-57% after just 18-69 hours of mechanical ventilation and sedation. Ventilator-induced diaphragm atrophy could cause a patient to become ventilator-dependent. Patients in intensive care units (ICU) who become dependent on mechanical ventilation (MV) are at high risk of complications such as ventilator-acquired pneumonia (VAP) and nosocomial infections and are seven times more likely to die in the ICU. It has been reported that in 2008, 1.58 million ICU patients in the United States require MV every year, of which 20-30% (about 400,000 mechanically ventilated patients) have difficulty weaning from MV and are at risk of becoming ventilator-dependent. Three methods have been used to reverse or slow down atrophy in disused diaphragm muscles by stimulating the phrenic nerves and are discussed below. Method 1. Phrenic nerve pacing uses electrodes implanted in the chest to directly stimulate the phrenic nerves. The Mark IV Breathing Pacemaker System available from Avery Biomedical Devices, Inc. of Commack, New York, USA, is a diaphragmatic or phrenic nerve stimulator that has surgically implanted receivers and electrodes mated to an external transmitter by antennas worn over the implanted receivers. Implanting electrodes and other implantable components for phrenic nerve pacing requires significant surgery. The surgery is risky and complicated by the fact that phrenic nerves are thin (approximately 2 mm in diameter) and delicate. The surgery involves significant cost. Method 2. Laproscopic diaphragm pacing developed by biomedical engineers and physician researchers at Case Western Reserve University is another technique for controlling breathing. Laproscopic diaphragm pacing involves placing electrodes at motor points of the diaphragm. Method 3. A method using intravascularly implanted electrodes to stimulate a nerve has been developed by Joaquin A