A catheter includes multiple primary leads to deliver energy for ligating a hollow anatomical structure. Each of the primary leads includes a resistive element located at the working end of the catheter. Separation is maintained between the leads such that each lead can individually receive power. The catheter can include a lumen to accommodate a guide wire or to allow fluid delivery. Energy is applied until the diameter of the hollow anatomical structure is reduced to the point where occlusion is achieved. In one embodiment, a balloon is inflated to place the resistive elements into apposition with a hollow anatomical structure and to occlude the structure before the application of energy. The inflated balloon impairs blood flow and facilitates the infusion of saline, or medication, to the hollow anatomical structure in order to reduce the occurrence of coagulation and to improve the heating of the structure by the catheter.