Optimization of energy delivery for various applications
Energy is transmitted to a body lumen or passageway in the form of pulsed electric fields (PEFs) and in a manner which provides focal therapy. In some embodiments, PEFs are delivered through independent electrically active electrodes of an energy delivery body, typically in a monopolar fashion. Such delivery concentrates the electrical energy over a smaller surface area, resulting in stronger effects than delivery through an electrode extending circumferentially around the lumen or passageway. It also forces the electrical energy to be delivered in a staged regional approach, mitigating the effect of preferential current pathways through the surrounding tissue. Focal delivery of PEFs can provide increased tissue lethality by employing precise timing and sequencing of energy delivery to the electrodes.
1. A system for treating a passageway within a body comprising:
a catheter comprising a first electrode and at least one additional electrode disposed near its distal end, wherein the distal end of the catheter is configured to be positioned within the passageway so that the first electrode and the at least one additional electrode are able to transmit pulsed electric field energy to an inner circumference of the passageway which destroys at least a portion of cells within a cellular matrix along the inner circumference without destroying the cellular matrix; and
a generator in electrical communication with the first electrode and the at least one additional electrode, wherein the generator includes at least one energy delivery algorithm that
a) provides an electric signal of the pulsed electric field energy to the first electrode so as to prioritize energy delivery through the first electrode to create a first treatment area and
b) switches to individually provide an electric signal of the pulsed electric field energy to each of the at least one additional electrodes so as to prioritize energy delivery through each of the at least one additional electrodes when provided the electric signal so as to create an additional treatment area corresponding to each of the at least one additional electrodes,
wherein the first treatment area and the additional treatment areas extend along the inner circumference of the passageway so as to create a functionally continuous treatment area spanning the inner circumference.
2. The system as in claim 1 , wherein the passageway is disposed within a heart and the distal end of the catheter is configured to be positioned within the heart, and wherein the at least one energy delivery algorithm includes signal parameters causing the functionally continuous treatment area to comprise an electrical disconnection between a pulmonary vein and a left atrium so as to treat arrhythmia.
3. The system as in claim 2 , wherein the passageway comprises the pulmonary vein and the distal end of the catheter is configured to be positioned within the pulmonary vein.
4. The system as in claim 3 , wherein the signal parameters cause the functionally continuous treatment area to comprise a transmural lesion.
5. The system as in claim 1 , wherein the passageway comprises an airway within a lung and the distal end of the catheter is configured to be positioned within the airway, and wherein the at least one energy delivery algorithm includes signal parameters causing the functionally continuous treatment area to comprise a vacancy of cell types while maintaining a cartilage layer of the airway.
6. The system as in claim 5 , wherein the cell types include epithelial cells, goblet cells and/or submucosal gland cells.
7. The system as in claim 5 , wherein the functionally continuous treatment area has a depth of up to and not beyond 2.5 cm.
8. The system as in claim 1 , wherein the pulsed electric field energy is biphasic.
9. The system as in claim 1 , wherein the at least one energy delivery algorithm provides pulsed electric field energy to the at least one of the plurality of electrodes for less than or equal to 10,000 μs to create the first treatment area and/or each of the at least one additional treatment areas.
10. The system as in claim 9 , wherein the at least one energy delivery algorithm provides pulsed electric field energy to the at least one of the plurality of electrodes for less than or equal to 500 μs to create the first treatment area and/or each of the at least one additional treatment areas.
11. The system as in claim 10 , wherein the at least one energy delivery algorithm provides pulsed electric field energy to the at least one of the plurality of electrodes for 5 μs-50 μs to create the first treatment area and/or each of the at least one additional treatment areas.
12. The system as in claim 1 , wherein the pulsed electric field energy is comprised of 40-500 packets.
13. The system as in claim 12 , wherein the pulsed electric field energy is comprised of less than or equal to 10 packets.
14. The system as claim 1 , wherein the pulsed electric field energy is delivered in a monopolar arrangement.
15. The system as in claim 1 , wherein the at least one additional electrode comprises two to seven additional electrodes.
16. The system as in claim 1 , wherein the at least one energy delivery algorithm provides the electric signal of the pulsed electric field energy to each of the first electrode and at least one additional electrode in series.
17. The system as in claim 1 , wherein the first treatment area and the at least one additional treatment areas overlap.
18. The system as in claim 17 , wherein the at least one energy delivery algorithm is configured to provide the electric signal of the pulsed electric field energy to the first electrode in a plurality of phases and to the at least one additional electrodes in a plurality of differing phases, wherein the plurality of phases and the plurality of differing phases do not coincide.
19. The system as in claim 18 , wherein the plurality of phases and the plurality of differing phases form a repetitive pattern.
20. The system as in claim 18 , wherein the at least one energy delivery algorithm provides maintenance pulsed electric field energy to the first electrode and/or the at least one additional electrodes in between phases, wherein the maintenance pulsed electric field energy has a lower voltage than the pulsed electric field energy.
21. The system as in claim 20 , wherein the maintenance pulsed electric field energy has a voltage of less than half that of the pulsed electric field energy.
22. The system as in claim 1 , wherein the first electrode and the at least one additional electrode are mounted on or imbedded in an expandable member.
23. The system as in claim 1 , wherein the first electrode and the at least one additional electrode comprises a plurality of wires or ribbons forming an electrode delivery body having an expandable basket shape, wherein a portion of the basket shape is insulated.