A catheter body includes a proximal portion, an intermediate portion extending from the proximal portion and defining a longitudinal axis, and a distal portion extending from the intermediate portion and terminated by a distal end of the catheter body; the distal portion forms a coil about a central loop axis, which is substantially parallel to the longitudinal axis. A first lumen extends through the proximal and intermediate portions of the catheter body and is terminated at an opening proximal to an ablation section, which is formed along the coil.