A positioning device configured for introduction within a body lumen. Some embodiments include a catheter shaft with a longitudinal axis; an expandable element coupled along a length of the shaft, the expandable element being substantially thin and flexible in an unexpanded state and exerting a gentle outward force in an expanded state; and a deflection mechanism located within the shaft, wherein the deflection mechanism is flexible when in a non-deflected state and wherein, in the deflected state, the deflection curves in a predetermined lateral direction such that the positioning device laterally deflects the body lumen. In some embodiments, the deflection is a lateral curve that moves the body lumen away from a surgical site, such as a cardiac ablation site.