A method and apparatus for ablation of cardiac tissue at a selected cardiac location is achieved by providing at least one flexible elongated guide facility having a first end, a second end, and an intermediate portion extending between the first and second ends and by providing an ablation instrument which includes at least a pair of relatively moveable clamping jaws being disposed to engage and ablate the selected cardiac location. Each guide facility is adapted for introduction into a patients chest through an opening and for advancement to the selected cardiac location such that the intermediate portion engages the selected cardiac location and the guide facility is withdrawn through the instrument receiving passage. At least one jaw of the ablation instrument engages with the guide facility and is guided to the selected cardiac location with the aid of the guide facility to ablate the selected cardiac location.
