Patent ID: 7686802

Claim:
A catheter comprising: a catheter shaft having a distal end, the distal end of the catheter shaft having an insulating material and a diameter; and an ablation electrode forming a junction with the distal end of the shaft, the ablation electrode having an exposed surface; wherein, extending from the junction, the exposed electrode surface has a first diameter portion with a first diameter that is smaller than the diameter of the distal end of the shaft, the first diameter portion forming an angle with the insulating material; and wherein the exposed electrode surface has a second diameter portion with a second diameter that is larger than the first diameter of the first diameter portion, the second diameter portion having a largest diameter that is smaller than a length of the second diameter portion; and wherein the exposed electrode surface further comprises a transition face extending from the first diameter portion to the second diameter portion, the transition face forming an approximately ninety degree angle with the first diameter portion; and wherein the insulating material, the first diameter portion and the transition face form a recessed region that allows blood to flow across the first diameter portion and the transition face when the electrode is placed in a blood flow.