A catheter is disclosed including an elongated shaft having a distal end and a proximal end, where the catheter includes a thermal element at the distal end thereof. The thermal element may be used in an ablation procedure or other procedure to heat a tissue adjacent a vessel. The configuration of the distal end of the elongated shaft at or near the distal tip may encourage the cooling of or transferring of heat from the vessel wall. The configurations may include protrusions extending from and indentations extending into the shaft, which may manipulate the flow of fluid through a vessel in which the catheter has been inserted. Alternatively or additionally, a cap or thin insulative layer may be placed at or near the distal tip of the catheter shaft to cool the wall of the vessel.