Devices and methods for treatment of heart failure by splanchnic nerve ablation
A method for treating a heart failure patient by ablating a nerve of the splanchnic sympathetic nervous system to increase venous capacitance and reduce pulmonary blood pressure. A method including: inserting a catheter into a vein adjacent the nerve, applying stimulation energy and observing hemodynamic effects, applying ablation energy and observing hemodynamic effects, applying simulation energy after the ablation and observing hemodynamic effects.
1. A method for increasing splanchnic venous capacitance in a patient, comprising:
positioning an endovascular catheter comprising a proximal region, a flexible shaft, and a distal region, wherein the flexible shaft connects the proximal and distal regions and is a length sufficient to access a T9, T10, or T11 intercostal vein of the patient relative to an access location when the proximal region remains external to the patient, and wherein the distal region is configured to be advanced through patient vasculature and dimensioned to terminate in the T9, T10 or T11 intercostal vein and make contact with an inner wall of the T9, T10 or T11 intercostal vein and comprises at least one ablation element, at least one stimulation element, and at least one detection element;
advancing the distal region through an azygous vein;
advancing the distal region from the azygous vein and into the T9, T10, or T11 intercostal vein;
activating the at least one ablation element;
ablating a greater splanchnic nerve using energy generated with the at least one ablation element; and
removing the endovascular catheter from the patient.
2. The method of claim 1 , further comprising confirming positioning success.
3. The method of claim 1 , further comprising confirmation of an ablation of the greater splanchnic nerve.
4. The method of claim 1 , wherein the proximal region comprises an energy source and a controller with embedded logic and software.
5. The method of claim 4 , wherein the proximal region further comprises a user interface.
6. The method of claim 1 , wherein the at least one ablation element is associated with the at least one stimulation element.
7. The method of claim 1 , wherein the at least one detection element comprises at least one of a systemic, pulmonary arterial and venous pressure transducer, a cardiac output detector, or a blood flow monitor.
8. The method of claim 1 , further comprising positioning a second detection element in a different part of the patient vasculature than the T9, T10 or T11 intercostal vein.
9. The method of claim 1 , wherein the at least one ablation element comprises at least one of an electrode, a cryo console, a drug delivery device, an injection of neurolytic blocking agent, an ultrasound device, a radio frequency device, a thermal ablation device, or a laser emitter.
10. The method of claim 9 , wherein the at least one ablation element comprises a radio frequency device that outputs an electrical current having a frequency in a range of 350 to 500 kHz and a power in a range of 5 to 50 W.
11. The method of claim 1 , wherein the at least one detection element comprises a blood pressure transducer.
12. The method of claim 1 , wherein the at least one detection element comprises a tissue temperature sensor.
13. The method of claim 1 , wherein the at least one detection element comprises a hemodynamic sensor.
14. The method of claim 1 , wherein the at least one detection element comprises an environmental temperature sensor.
15. The method of claim 1 , wherein the at least one detection element comprises a tissue impedance sensor.
16. The method of claim 1 , wherein the distal region comprises a deployable structure comprising at least one of a balloon, a cage, a basket, a preformed shape, lasso or loop.
17. The method of claim 1 , wherein the access location is a radial, brachial, subclavian, jugular or femoral vein.
18. The method of claim 1 , wherein the positioning step is proceeded by an introduction and advancement of a guide-wire to facilitate advancement of the endovascular catheter through the patient vasculature.
19. The method of claim 1 , wherein the at least one ablation element and the at least one stimulation element are positioned on the endovascular catheter relative to one another so that an area in which a stimulation signal delivered by the at least one stimulation element correlates with an ablation zone in which the energy delivered by the at least one ablation element is sufficient to cause irreversible ablation of the greater splanchnic nerve.
20. The method of claim 2 , wherein confirming the positioning success of the distal region is performed by an automated algorithmic process to confirm a change in at least one selected hemodynamic or physiological parameter.
21. The method of claim 20 , further comprising selecting an electrode or an electrode pair of the at least one stimulation element, recording a baseline of the selected hemodynamic parameter, delivering a stimulation pulse with a current (I), a pulse width (pw), a frequency (F) and a duty cycle (D) in about I=0-10 mA, pw=100-1000 us, F=20-40 Hz, D=50% pulsing between 20-60 s; and recording a measurement of the selected hemodynamic parameter.
22. The method of claim 21 , further comprising determining if the measurement of the hemodynamic parameter is >20% from the baseline, allowing the selected hemodynamic parameter to return to the baseline and repeating for at least three measurements, recording average measurements for the at least three measurements, and if a standard error is within +/−10%, confirming the change in the at least one hemodynamic parameter or physiological parameter.
23. The method of claim 20 , wherein the at least one selected hemodynamic or physiological parameter is selected from the group of responses consisting of pupil dilation, increased sweating, increased heart rate, increased blood pressure, and increased mean arterial pressure.
24. The method of claim 1 , further comprising
applying electrical stimulation to the greater splanchnic nerve;
detecting physiological changes to confirm positioning success; and
re-applying electrical stimulation to the greater splanchnic nerve to confirm irreversible ablation of the greater splanchnic nerve.
25. The method of claim 24 further comprising re-positioning the distal region, and repeating the applying the electrical stimulation until positioning success is confirmed.
26. A method for increasing splanchnic venous capacitance in a patient, comprising:
positioning an endovascular catheter comprising a proximal region, a flexible shaft, and a distal region, wherein the flexible shaft connects the proximal and distal regions and is a length sufficient to access a T9, T10, or T11 intercostal vein of the patient relative to an access location when the proximal region remains external to the patient, the distal region comprising at least one ablation element;
advancing the distal region through an azygous vein;
advancing the distal region from the azygous vein and into the T9, T10, or T11 intercostal vein;
activating the at least one ablation element;
ablating a greater splanchnic nerve using energy generated with the at least one ablation element; and
removing the endovascular catheter from the patient.
27. The method of claim 26 , further comprising confirming a proper position of the at least one ablation element in the T9, T10 or T11 intercostal vein.
28. The method of claim 26 , further comprising confirming that the greater splanchnic nerve has been ablated.
29. The method of claim 26 , wherein the at least one ablation element comprises a balloon, the method further comprising expanding the balloon in the T9, T10, or T11 intercostal vein prior to the ablating with the at least one ablation element.
30. The method of claim 29 , wherein the balloon has a cylindrically shaped expanded configuration, wherein expanding the balloon comprises expanding the balloon towards the cylindrically shaped configuration.
31. The method of claim 29 , wherein expanding the balloon comprises expanding the balloon to have a diameter from 2 mm-6 mm.
32. The method of claim 29 , wherein expanding the balloon comprises distending a wall of the T9, T10, or T11 intercostal vein.
33. The method of claim 26 , wherein advancing the distal region from the azygous vein and into the T9, T10, or T11 intercostal vein comprises advancing the distal region into a right T9, T10, or T11 intercostal vein.