US 5,423,807 A · Cryogenic mapping and ablation catheter

Abstract

The invention provides a catheter for ice mapping and ablation and a method of ablation using the catheter. The catheter includes at least two conduits for circulating a refrigerating fluid adjacent an ablation device located at the end of a catheter. The refrigerated ablation device is used to chill a localized region of myocardial tissue, thereby permitting the resulting change in electrical activity to be determined. In response to the test results, the ablation device may be used to make a lesion in the myocardial tissue to correct a cardiac arrhythmia. In one embodiment, the ablation device is an electrode which uses radio frequency energy to ablate the myocardial tissue. Alternatively, the ablation device is an electrode adapted for direct current ablation. In another embodiment, the electrode is replaced with an optical fiber in communication with a laser which uses the laser's light energy to ablate tissue. Yet another embodiment is a cryogenic catheter having combined or separate mapping and ablation devices. In another embodiment, a cryogenic catheter is provided having an inner conduit with a stepped down diameter. The embodiments may include provisions for steering the catheter and for stabilizing the ablation device at the proposed lesion site.

Claims16

Dependent claims

A cryogenic catheter comprising:

a first conduit, having a proximal end and a distal end, concentric with a second conduit, said first conduit permitting a cooling fluid to flow from said proximal end to said distal end, said second conduit, having a proximal end and a distal end, permitting said cooling fluid to flow from said distal end to said proximal end;
a conductive boiling chamber connecting said distal end of said first conduit and said distal end of said second conduit, said boiling chamber permitting boiling of said cooling fluid into a gaseous state;
said first conduit having a flow restrictive section adapted to control delivery of said cooling fluid to said boiling chamber at a pressure greater than a vapor-pressure of said cooling fluid at room temperature and less than 300 pounds per square inch;
a first electrode wire in conductive contact with said boiling chamber;
and
second electrode wire isolated from said boiling chamber.

3 more elements

Dependencies are inferred from the claim text.

Cryogenic mapping and ablation catheter

Life of this patent

Cryogenic mapping and ablation catheter

Life of this patent

Abstract

Claims16