Ablation system with force control
An ablation system comprises: an ablation catheter and a console. The ablation catheter comprises: a shaft including a proximal end, a distal portion and a distal end; an ablation element configured to deliver energy to tissue; and a force maintenance assembly comprising a force maintenance element and configured to control and/or assess contact force between the ablation element and cardiac tissue. The console is configured to operably attach to the ablation catheter and comprises: an energy delivery assembly configured to provide energy to the ablation element. Methods of ablating tissue are also provided.
1. A method of performing an ablation procedure comprising:
advancing an ablation catheter into the heart of a patient, the ablation catheter comprising:
a shaft including an irrigation lumen, a proximal end, a distal portion, and a distal end;
an ablation element configured to deliver energy to tissue; and
a force maintenance assembly comprising a force maintenance element configured to control and/or assess contact force between the ablation element and cardiac tissue, wherein the force maintenance element comprises a piston including the ablation element, the piston extending from the shaft distal end and at least a portion of the piston translates linearly within the shaft distal portion,
wherein the piston comprises a hydraulic piston, and wherein the force maintenance assembly is configured to control a hydraulic fluid flow to the hydraulic piston to adjust, maintain, and control a hydraulic pressure that the hydraulic piston exerts on and/or against the tissue;
applying force between the ablation element and cardiac tissue via the force maintenance assembly; and
a console delivering ablation energy to tissue with the ablation element.
2. The method according to claim 1 , wherein the hydraulic piston comprises at least one irrigation port configured to allow the hydraulic fluid to exit from the irrigation lumen.
3. The method according to claim 2 , wherein the hydraulic pressure comprises a differential pressure between the flow of hydraulic fluid from the force maintenance assembly and the flow of hydraulic fluid exiting the irrigation lumen.
4. The method according to claim 1 , wherein the console further comprises a force maintenance module.
5. The method according to claim 4 , wherein the force maintenance module is configured to adjust the force maintenance assembly.
6. The method according to claim 4 , wherein the force maintenance module is configured to provide a control signal to the force maintenance assembly.
7. The method according to claim 4 , wherein the force maintenance module is configured to operatively interact with the force maintenance assembly to control a parameter selected from the group consisting of: the fluid flow to the hydraulic piston; fluid pressure within the hydraulic piston; and combinations thereof.
8. The method according to claim 1 , wherein the ablation catheter further comprises at least one mapping electrode.
9. The method according to claim 1 , wherein the ablation catheter further comprises an articulating tip assembly.
10. The method according to claim 9 , wherein the articulating tip assembly comprises a spherical member and a cavity that rotatably engages the spherical member.
11. The method according to claim 1 , wherein the ablation catheter further comprises a contact sensor configured to produce a signal representative of the amount of contact between the ablation element and tissue.
12. The method according to claim 1 , wherein the energy delivered by the ablation element comprises energy selected from the group consisting of: thermal energy; heat energy; cryogenic energy; electromagnetic energy; radio frequency (RF) energy; microwave energy; light energy; light energy provided by a laser; sound energy; subsonic energy; ultrasound energy; chemical energy; and
combinations thereof.
13. The method according to claim 1 , wherein the energy delivered by the ablation element comprises at least two forms of energy selected from the group consisting of: electromagnetic energy; RF energy;
microwave energy; light energy; laser light energy; cryogenic energy; ultrasound energy; and combinations thereof.
14. The method according to claim 1 , wherein the force maintenance assembly is configured to dynamically respond to movement of a heart wall.
15. The method according to claim 1 , wherein the force maintenance assembly is configured to compress up to a maximum compression distance, and wherein the maximum compression distance comprises a distance between 0.1 mm and 10 mm.
16. The method according to claim 1 , further comprising a locking element configured to lock the force maintenance assembly to prevent linear and/or angular movement of the ablation element with respect to the shaft.
17. The method according to claim 1 , wherein the force maintenance assembly further comprises at least one displacement sensor configured to produce a signal correlating to a travel distance of the force maintenance assembly.
18. The method according to claim 17 , wherein the system is configured to determine when the travel distance is equal to a maximum compression distance based on the sensor signal.