Instruments and methods for accessing an anatomic space

An epicardial lead access instrument for implanting an epicardial lead into the myocardium at an epicardial implantation site between the epicardium and the pericardium accessed through the thorax from a skin incision, the epicardial lead of the type having an elongated lead body extending between at least one proximal electrical connector element and a distal fixation mechanism extending from a distal electrode head, the lead body supporting at least one electrode coupled through an electrical conductor to a proximal electrical connector element, the access instrument comprising:

• an elongated access instrument body formed of an elastomer extending between a access instrument body proximal end and a access instrument body distal end, the access instrument body having a access instrument body axis, a access instrument body width in a width direction with respect to the access instrument body axis, and a access instrument body thickness in a thickness direction substantially orthogonal to the width direction, the access instrument body width exceeding the access instrument body thickness enabling bending of the access instrument body in the thickness direction and resisting bending of the access instrument body in the width direction, the access instrument body enclosing an inflation lumen extending from the access instrument body proximal end through the access instrument body to an inflation lumen distal end opening and a working lumen extending from the access instrument body proximal end through the access instrument body to the access instrument body distal end dimensioned to enable passage of the lead body and distal fixation mechanism therethrough;
• and
• a distal header coupled to the access instrument body distal end comprising a header body supporting a header plate extending laterally of the access instrument body axis in the width direction to a atraumatic plate rim, the header plate having a first plate side bounded by the atraumatic plate rim, the header body enclosing a header lumen extending between the working lumen at the access instrument body distal end and a working lumen exit port through the first plate side, and an inflatable balloon mounted to the header plate adapted to be inflated by introduction of inflation media through the inflation lumen distal end opening into an inflation space between the balloon and at least a portion of the first plate side,
• whereby the access instrument is adapted to be advanced through the thorax from the skin incision between the epicardium and the pericardium to dispose the deflated balloon and first plate side toward the epicardium at the epicardial implantation site to enable inflation of the balloon to position the working lumen port facing toward and spaced from the epicardium allowing passage of the distal fixation mechanism from the working lumen exit port and fixation to the epicardium.