Apparatus and methods for placing leads using direct visualization

A system for delivering a lead into a body cavity of a patient, comprising:

• an imaging device comprising a proximal end and an expandable distal end having an inner balloon and an outer balloon, the outer balloon being concentric with the inner balloon, the expandable distal end including a channel defined between the inner balloon and the outer balloon, the imaging device further comprising at least one lumen extending between the proximal and distal ends and an imaging assembly for imaging through the expandable distal end while the distal end is in a fully expanded configuration and manipulated relative to a tissue wall;
• an elongate rail comprising a proximal end and a distal end positionable through the at least one lumen of the imaging device and the channel, the elongate rail comprising a fixation element on the distal end for securing the distal end to a delivery location on the tissue wall;
• and
• a lead comprising a proximal end, a distal end arranged for introduction through the at least one lumen of the imaging device guided by the elongated rail, and one or more electrodes on the distal end.