Guided cardiac ablation catheters

Abstract

Guided ablation instruments are disclosed for creating lesions in tissue, especially cardiac tissue for treatment of arrhythmias, including atrial fibrillation. In one aspect of the invention, a percutaneous catheter is disclosed with an endoscope positionable in the instrument's distal end region to obtain an image. The image allows the clinician to determine whether contact has been achieved (or blood has been cleared from an ablative energy transmission path) before ablation begins or while ablation is occurring. In one embodiment, percutaneous ablation catheters are disclosed having at least one central lumen and one or more balloon structures at the distal end region of the instrument. Also disposed in the distal end region are an illuminating light source and an endoscope capable of collecting sufficient light to relay an image to the user. The instruments can further include an ablation element.

What is claimed is: 
     
         1 . A cardiac ablation instrument for treatment of atrial fibrillation comprising:
 a catheter adapted for disposition within a heart;   an expandable balloon member coupled to the catheter and adapted for positioning proximate to a pulmonary vein;   an ablation element within the balloon member for creating at least one lesion in the vicinity of the pulmonary vein; and   a reflectance sensor for positioning the ablation element relative to the pulmonary vein.   
     
     
         2 . The instrument of  claim 1 , wherein the instrument further comprises at least one orientation marker. 
     
     
         3 . The instrument of  claim 2 , wherein the marker is located on the ablation element. 
     
     
         4 . The instrument of  claim 2 , wherein the marker is on the expandable balloon of the instrument. 
     
     
         5 . The instrument of  claim 2 , wherein the marker is detectable fluoroscopically. 
     
     
         6 . The instrument of  claim 1 , wherein the reflectance sensor is capable of sensing contact between at least a portion of the instrument and cardiac tissue. 
     
     
         7 . The instrument of  claim 1 , wherein the reflectance sensor is capable of capturing an image. 
     
     
         8 . The instrument of  claim 1 , wherein the reflectance sensor comprises at least one optical fiber. 
     
     
         9 . The instrument of  claim 1 , wherein the reflectance sensor comprises an endoscope. 
     
     
         10 . The instrument of  claim 9 , wherein the endoscope further comprises an optical field enhancing element. 
     
     
         11 . The instrument of  claim 9 , wherein the endoscope has a field of view greater than about 70 degrees. 
     
     
         12 . The instrument of  claim 9 , wherein the endoscope has a field of view greater than about 90 degrees. 
     
     
         13 . The instrument of  claim 9 , wherein the endoscope has a depth of field of greater than about 13 mm. 
     
     
         14 . The instrument of  claim 9 , wherein the endoscope has a depth of field of greater than about 25 mm. 
     
     
         15 . The instrument of  claim 9 , wherein the endoscope has a depth of field of greater than about 35 mm. 
     
     
         16 . The instrument of  claim 9 , wherein the endoscope has an f number less than 4. 
     
     
         17 . The instrument of  claim 9 , wherein the endoscope has an f number less than 3. 
     
     
         18 . The instrument of  claim 9 , wherein the endoscope has an f number less than 2.5. 
     
     
         19 . The instrument of  claim 1 , wherein the reflectance sensor is fixed relative to the balloon. 
     
     
         20 . The instrument of  claim 1 , wherein the reflectance sensor is slidably disposed within a lumen of the catheter. 
     
     
         21 - 80 . (canceled)