Distal balloon impedance and temperature recording to monitor pulmonary vein ablation and occlusion
AssigneeMedtronic CryoCath LP
InventorsBoaz Avitall, Catherine R. Condie
Life of this patent
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Abstract
A cryoablation method, system, and device that allows for real-time and accurate assessment and monitoring of PV occlusion and lesion formation without the need for expensive imaging systems and without patient exposure to radiation. The system includes a cryoballoon catheter with a cryoballoon, a distal electrode, a proximal electrode, and a temperature sensor. Impedance measurements recorded by the electrodes may be used to predict ice formation, quality of pulmonary vein occlusion, and lesion formation.
Claims20
A system for cryoablating tissue, the system comprising:
- a cryoablation device, the cryoablation device including:
- a balloon coupled to a distal portion of the cryoablation device;
- a first electrode located immediately distal to the balloon;
- and
- a second electrode located a distance from the first electrode and distal to the balloon;
- and
- a console including a processor, the processor configured to:
- record a first plurality of impedance measurements from the first electrode and the second electrode;
- record a second plurality of impedance measurements from the first electrode and the second electrode;
- determine a first impedance slope using the first plurality of impedance measurements from the first electrode and determine a second impedance slope using the second plurality of impedance measurements from the first electrode;
- compare the first slope to a first reference slope and compare the second slope to a second reference slope;
- and
- determine whether the balloon catheter is creating a permanent lesion in the tissue based on the comparison of the first slope to the first reference slope and the comparison of the second slope to the second reference slope.
A system of for cryoablating an ostium of a pulmonary vein, the system comprising:
- a cryoablation device, the cryoablation device including:
- a balloon coupled to a distal portion of the cryoablation device;
- and
- at least one electrode located immediately distal to the balloon;
- and
- a console including a processor, the processor being configured to:
- record a first set of impedance measurements from the at least one electrode;
- record a second set of impedance measurements from the at least one electrode;
- determine a first impedance slope using the first set of impedance measurements and determine a second impedance slope using the second set of impedance measurements;
- determine an impedance curve using the first impedance slope and the second impedance slope;
- and
- determine, based on the impedance curve:
- whether the cryoablation device is creating a permanent lesion in the ostium of the pulmonary vein;
- whether the balloon is not occluding the pulmonary vein;
- whether the balloon is partially occluding the pulmonary vein;
- and
- whether the balloon is completely occluding the pulmonary vein.
A system for cryoablating a pulmonary vein ostium, the system comprising:
- a cryoablation device, the cryoablation device including:
- a balloon coupled to a distal portion of the cryoablation device;
- and
- a first electrode located immediately distal to the balloon;
- a second electrode located distal to the first electrode;
- and
- at least one thermocouple proximate the second electrode;
- and
- a console including a processor, the processor being configured to:
- continuously record impedance measurements from the first electrode while the cryoablation device is in use;
- continuously record impedance measurements from the second electrode while the cryoablation device is in use;
- continuously recording temperature measurements from the thermocouple when the cryoablation device is in use;
- and
- determine that a circumferential ablation lesion will be formed around the pulmonary vein ostium when the processor records an impedance measurement from the first electrode of at least 2000 Ω and records a temperature measurement from the thermocouple of−37.8±3.3° C. within 120±30 sec from an onset of a flow of coolant within the balloon.
Dependencies are inferred from the claim text.