Pericardial needle mechanism

A method for puncturing a pericardium of a heart of a subject, the method comprising:

• distally advancing a surgical tool toward a heart of a subject, the surgical tool (a) shaped to define a distal end having an outer surface at least part of which is transparent, and (b) shaped to define a suction port at a distal portion of the surgical tool;
• drawing a portion of the pericardium into the surgical tool by applying suction to the pericardium through the suction port;
• and
• activating a user control to distally advance a driving assembly of the surgical tool, the distal advancement of the driving assembly having a distal-mode first phase and a distal-mode second phase,
• the distal-mode first phase distally advancing a needle into the suction port while the needle is rotationally stationary with respect to a longitudinal axis of the surgical tool, thereby puncturing the portion of the pericardium within the suction port, and
• the distal-mode second phase rotating the needle in a first rotational direction while a puncturing tip of the needle is between the pericardium and myocardium of the heart.

Apparatus comprising:

• a surgical tool shaped to define a lumen and comprising a handle disposed at a proximal end of the surgical tool;
• a driving assembly disposed within the handle and comprising proximal and distal portions, the proximal and distal portions being slidably coupled to each other;
• and
• a needle slidably disposed within the lumen of the surgical tool and coupled to the proximal portion of the driving assembly such that (i) during distal advancement of the driving assembly with respect to the handle the needle is advanced distally within the lumen of the surgical tool, the needle being rotationally stationary with respect to a longitudinal axis of the surgical tool, and (ii) subsequently to the needle being advanced distally within the lumen of the surgical tool, distal advancement of the distal portion of the driving assembly with respect to the proximal portion of the driving assembly rotates the needle in a first rotational direction around the longitudinal axis of the surgical tool.