An ablation catheter 50 for performing a medical procedure on a patient comprising an elongated, flexible, tubular body member 76 having a proximal end, a distal end and a lumen extending therebetween a first control shaft 48 coaxially disposed and slidingly received within the lumen of the tubular body member and a flexible carrier assembly 85 retractable within the tubular body member including at least two discrete ablation elements configured to deliver energy to tissue wherein retraction of the first control shaft causes the at least two discrete ablation elements to transform from a near linear geometry to a partial helical geometry and a second control shaft 57 slidingly received within the tubular body member, wherein a proximal end of the carrier assembly is attached to the second control shaft, and a distal end of the carrier assembly is attached to the first control shaft.
