A method and system for ablation of cardiac tissue in a living being via the esophagus is provided. The method includes the step of introducing a photodynamic substance to the cardiac tissue. A deformable, elongated body defining a proximal end and a distal end is inserted into an esophagus of the living being. The distal end of the elongated body is located proximate the cardiac tissue. A first set of electromagnetic radiation is then directed from the distal end of the elongated body towards the cardiac tissue. Reflective and opaque surfaces at the distal end of the elongated body may be used to direct the electromagnetic radiation and an expandable membrane at the distal end may be used to urge the distal end of the elongated body to a predetermined position within the esophagus.
