Snaring systems and methods
View Patent ↗Snaring systems and methods involve engaging objects such as pacemaker pacing leads within a patient. Physicians can use snaring systems having loops, tags, and roller mechanisms to remove a pacing leads from a patient. For example, snaring systems can be inserted through a jugular access site, engaged with a pacemaker pacing lead, and withdrawn through the jugular access site so as to remove a portion of the pacing lead. Lead extraction techniques can be employed to further dislodge the pacing lead from the patient.
1. A snaring system for engaging an object within a patient's body, the system comprising:
an elongate element having a proximal end and a distal end, wherein the elongate element terminates at the distal end; and
a sheath having a central longitudinal axis, the sheath comprising:
a wall forming an inner surface, an outer surface and a cross section of the inner surface and outer surface, wherein the cross section has a central cross-sectional axis that is coterminous with the central longitudinal axis;
a lumen in the wall of the sheath and through which at least a portion of the elongate element extends, wherein the distal end of the elongate element extends distally of the lumen and is configured to form an open loop distally thereof, wherein the lumen has a lumen longitudinal axis parallel with and radially offset from the central longitudinal axis; and
a central lumen formed by the inner surface of the wall and configured to receive a portion of the loop of the elongate element, wherein the central lumen has a central lumen longitudinal axis coterminous with the central longitudinal axis, wherein in an open position, the open loop extends from the lumen to a first position distally of the central lumen, and wherein in a closed position, a portion of the open loop extends from the lumen to a second position into the central lumen.
2. The snaring system according to claim 1 , further comprising a rotatable bearing in operative association with the loop, wherein the rotatable bearing is disposed along the loop at the distal end of the elongate element.
3. The snaring system according to claim 1 , wherein the distal end of the elongate element further comprises a tag, and wherein the central lumen of the sheath is configured to receive the tag.
4. The snaring system according to claim 1 , wherein the elongate element comprises a member selected from the group consisting of a flattened portion, a square crosssection portion, and a rectangular cross-section portion.
5. The snaring system according to claim 1 , further comprising a deflection mechanism coupled with the sheath.
6. A method of engaging a pacing lead disposed within a patient, the method comprising:
inserting a snaring system through a jugular or femoral access site of a patient, wherein the snaring system comprises:
an elongate element having a proximal and a distal end, wherein the elongate element terminates at the distal end; and
a sheath having a central longitudinal axis, the sheath comprising:
a wall forming an inner surface, an outer surface and a cross section of the inner surface and outer surface, wherein the cross section has a central cross-sectional axis that is coterminous with the central longitudinal axis;
a lumen in the wall of the sheath, and through which at least a portion of the elongate element extends, wherein the distal end of the elongate element extends distally of the lumen and is configured to form an open loop distally thereof, wherein the lumen has a lumen longitudinal axis parallel with and radially offset from the central longitudinal axis; and
a central lumen formed by the inner surface of the wall and configured to receive at least a portion of the open loop of the elongate element, wherein the central lumen has a central lumen longitudinal axis coterminous with the central longitudinal axis;
engaging the pacing lead with the snaring system, wherein the open loop grasps the pacing lead when the open loops extends from the lumen to a position distally of the central lumen and wherein the open loop pulls the pacing lead toward sheath when a portion of the open loop enters the central lumen;
sliding the open loop along a length of the pacing lead, so as to move a portion of the pacing lead toward the jugular or femoral access site of the patient; and
withdrawing the snaring system from the jugular or femoral access site, so as to remove at least a portion of the pacing lead from the patient.
7. The method according to claim 6 , wherein engaging the pacing lead comprises engaging the pacing lead with a roller mechanism of the snaring system.
8. The method according to claim 6 , wherein engaging the pacing lead comprises engaging the pacing lead with a capture mechanism of the snaring system.
9. The method according to claim 6 , wherein engaging the pacing lead comprises sliding the elongate element along the lumen.
10. A method of engaging an object disposed within a patient, the method comprising:
inserting a snaring system through an access site of a patient, wherein the snaring system comprises an elongate element and a sheath having a lumen through which the elongate element extends, the elongate element having a proximal end and a distal end, wherein the elongate element terminates at the distal end, and wherein distally of the lumen, the distal end comprises a distal loop, wherein the distal loop comprises a single wire and a rotatable roller mechanism disposed along the wire, wherein a distal end of the wire forms a tag end;
engaging the object with the rotatable roller mechanism and the tag end of the snaring system; and
withdrawing the snaring system toward the access site, so as to move at least a portion of the object toward the access site.
11. The method according to claim 10 , wherein the elongate element comprises a tag end disposed distal to the rotatable roller mechanism.
12. The method according to claim 10 , wherein the rotatable roller mechanism comprises a bearing having a tubular shape.
13. The method according to claim 10 , wherein the rotatable roller mechanism comprises a bearing having a spherical shape.
14. The method according to claim 10 , wherein the rotatable roller mechanism comprises a first cylindrical bearing defining a first central longitudinal axis and a second cylindrical bearing defining a second central longitudinal axis, and wherein the first central longitudinal axis is angularly offset from the second central longitudinal axis.
15. The method according to claim 14 , wherein the first central longitudinal axis is angularly offset from the second central longitudinal axis by about 90 degrees.
16. A snaring system for engaging an object within a patient's body, the system comprising:
a sheath having a lumen;
an elongate element extending through at least a portion of the lumen, wherein the elongate element has a proximal end and a distal end, wherein the elongate element terminates at the distal end, and wherein distally of the lumen, the distal end comprises a loop, wherein the distal loop comprises a single wire and a tag end formed by a distal end of the wire; and
a rotatable bearing disposed along the single wire and in operative association with the loop, wherein the rotatable bearing is disposed along the loop at the distal end of the elongate element.
17. The snaring system according to claim 16 , wherein the rotatable bearing is disposed on a first section of the loop, the loop comprising a second section distal to the first section and a third section proximal to the first section, such that the second section and the third section are in substantial parallel alignment.
18. The snaring system according to claim 17 , wherein the first section is in substantial perpendicular alignment with each of the second section and the third section.