Implementations described and claimed herein provide controlled access into the intra-pericardial space. In one implementation, a medical device comprises an outer sheath, an inner sheath, and a nose shaft. The outer sheath comprises a proximal end, a distal end, and a lumen extending between the proximal end and the distal end. The inner sheath extends through the lumen of the outer sheath and comprises a distal portion adapted to pierce the pericardial sac. The nose shaft is adapted to displace relative to a distal edge of the distal portion of the inner sheath. Displacing the distal portion of the inner sheath relative to the outer sheath until the nose shaft displaces relative to the distal edge provides controlled penetration into the intra-pericardial space.
