Abstract: A method for operating a steerable ablation catheter having at least one multiple-needle electrode at the tip section of an inner catheter within a heart chamber, wherein the ablation catheter including at least one multiple-needle electrode is inserted into a chamber of the heart to create a plurality of deep, large, and contiguous lesions by applying radiofrequency energy and cooled fluid to the electrode.

Abstract: An improved ablation catheter having a distal tip section made of flexible porous plastic material for fluid infusion and irrigation at its electrode comprises a catheter shaft having a distal section and at least one lumen extending therebetween, wherein the catheter is inserted into the chambers of the heart to create deep and large lesions by applying radiofrequency energy along with irrigated fluid to the electrode.

Abstract: An electrophysiology catheter suitable for radiofrequency ablation of cardiac tissues comprises a proximal section, a catheter shaft section and a distal section whereby a distal loop electrode having a temperature sensor and a close-loop temperature control. A conducting wire extends through the lumen and is connected to the loop electrode. The steerable catheter having a loop electrode is inserted into the chambers of the heart to create a continuous, non-linear lesion by supplying radiofrequency energy to said conducting wire.

Abstract: A catheter system comprising a delivery catheter with distal and proximal ends; a handle attached to the proximal end of the delivery catheter; the delivery catheter having an electrode deployment means where said electrode deployment means includes a retractable tip section comprising a plurality of deployable parallel electrodes. The tip section has a non-deployed state when it is positioned in the delivery catheter. On the other hand, the tip section has a distended deployed state when it is advanced out of the distal end of said delivery catheter; wherein the deployed electrodes on the tip section has a preformed shape in a parallel manner. This catheter is particularly useful for treating the patient having tachycardia as a result of its more effective electrodes arrangement for intimate tissue contact.

Abstract: A catheter system having a tip with fixation means for use in treatment of tissues, such as ablating tumors in a natural body conduit or cavity by applying RF energy through the tip, wherein the catheter system passes through a natural body opening to reach the target tissue, wherein the catheter system stays at a desired position via its fixation means, and delivers therapeutic RF energy to the target tissue for improved tissue treatment.

Abstract: This invention discloses an ablation catheter system with fixation means for use in treatment of cardiac tissues and in other medical applications, such as ablating tumors in a natural body conduit or cavity by applying RF energy, and an inner catheter having alternate energy sources for enhanced ablation. The catheter system passes through a natural body opening to reach the target tissue, where the catheter system stays in a desired position via its fixation means and delivers therapeutic energy selected from the group of laser energy, microwave, inductive radiofrequency and ultrasonic energy to the target tissue for improved treatment.

Abstract: An RF ablation apparatus has a delivery catheter with distal and proximal ends. A handle is attached to the proximal end of the delivery catheter. The delivery catheter has an electrode deployment means where said electrode deployment means includes a retractable tip section comprising a deployable electrode with portion of one side having a sharp edge. The tip section has a non-deployed state when it is positioned in the delivery catheter. On the other hand, the tip section has a distended deployed state when it is advanced out of the distal end of said delivery catheter. The deployed tip section has a preformed shape while the farther distal deployed electrode defines an ablation target along with portion of the forward side having a sharp edge on said electrode. The forward edge of the deployed electrode has a slightly curvature or an essentially straight shape. Said deployable electrode has ultrasonic imaging capabilities.

Abstract: A catheter system having a tip with fixation tines for use in treatment of tissues, such as ablating tumors in a natural body conduit or a cavity by applying RF energy through the tip, wherein the catheter system passes through a natural body opening to reach the target tissues, wherein the catheter system stays at a desired position via its fixation tines and delivers therapeutic RF energy to the target tissues for improved tissue treatment.

Abstract: An RF ablation device has a delivery catheter with distal and proximal ends. A handle is attached to the proximal end of the delivery catheter. The delivery catheter has an electrode deployment means where said electrode deployment means includes a retractable tip section comprising a deployable electrode with portion of one side having a sharp edge. The tip section has a non-deployed state when it is positioned in the delivery catheter. On the other hand, the tip section has a distended deployed state when it is advanced out of the distal end of said delivery catheter. The deployed tip section has a preformed shape while the farther distal deployed electrode defines an ablation target along with portion of the forward side having a sharp edge on said electrode. The forward edge of the deployed electrode has a slightly curvature or an essentially straight shape. Alternatively, the forward edge of the deployed electrode has sections with plurality of concave or convex curvatures.

Abstract: An improved catheter system having at least one electrode at its tip section, can be used in ablating the arrhythmogenic point of a patient. A catheter suitable for radiofrequency ablation of cardiac tissues comprises a catheter shaft having a distal section, a distal end, a proximal end and at least one lumen extending therebetween, wherein a rotatable ball electrode is disposed at the tip section of said catheter. In one embodiment, the ablation catheter has a temperature sensor and a close-loop temperature control mechanism. In another embodiment, the ablation catheter has fluid infusion and irrigation means at its distal tip section for creating a deep and large lesion by applying radiofrequency energy and cooled fluid to said electrode.

Abstract: An improved ablation catheter with at least one multiple-needle electrode can be used in ablating the arrhythmogenic region instead of an arrhythmogenic point of a patient. This catheter is particularly useful for treating the patient with atrial fibrillation (AFib) indications. A catheter suitable for radiofrequency ablation of cardiac tissues comprises a delivery catheter and an inner catheter having a distal section, a distal end, a proximal end and at least one lumen extending therebetween. The ablation catheter has a temperature sensor and a close-loop temperature control. The ablation catheter having at least one multiple-needle electrode is inserted into the chambers of the heart to create a plurality of deep, large, and contiguous lesions by applying radiofrequency energy and cooled fluid to said electrode.

Abstract: A catheter system suitable for electrophysiology mapping and radiofrequency ablation of cardiac tissue comprises a catheter shaft having a distal end, a proximal handle, and at least a lumen extending therebetween, wherein a distal section of the shaft is either a fixed curve or deflectable; and safety anchoring means being provided to maintain the integrity of the catheter by holding the tip electrode in place. In one embodiment, the safety means is a tip electrode with safety anchoring pins. In another embodiment, the safety means is a tip electrode with extended flexible stem having open slots on said stem.