APPARATUS AND METHODS FOR PUNCTURING TISSUE

1 . A method of confirming a position of a tip of a puncture device relative to a target tissue includes using an elongate puncture device having a tip electrode which is configured for collecting EGMs and for delivering energy for puncturing tissue, and comprises a step of collecting EGMs with the tip electrode to indirectly measure and monitor a pressure applied against the target tissue by the tip electrode of the elongate puncture device.

2 . The method of claim 1 , wherein the target tissue is a pericardium.

3 . The method of claim 1 , wherein the target tissue is a septum of a heart.

4 . The method of claim 3 , wherein the target tissue is an atrial septum.

5 . The method of any one of claims 1 to 5 , wherein the elongate puncture device delivers radiofrequency energy.

6 . The method of claim 5 , wherein the elongate puncture device is a radiofrequency stylet, trocar or guidewire.

7 . The method of claim 1 , wherein the EGMs are collected from a pericardium.

8 . The method of claim 1 , wherein the EGMs are collected from a septum of a heart.

9 . The method of claim 1 or 7 , wherein the elongate puncture device applies pressure against pericardial tissue.

10 . The method of claim 1 or 8 , wherein the elongate puncture device applies pressure against a septum of a heart.

11 . A method of puncturing a target tissue includes using an elongate puncture device having a tip electrode which is configured for collecting EGMs and for delivering energy for puncturing the target tissue, the method comprising collecting EGMs to indirectly measure and monitor a pressure applied against the target tissue by the elongate puncture device, thereby confirming a position of the tip electrode of the elongate puncture device relative to the target tissue.

12 . The method of claim 11 , wherein the target tissue is a pericardium.

13 . The method of claim 11 , wherein the target tissue is a septum of a heart.

14 . The method of claim 13 , wherein the target tissue is an atrial septum.

15 . The method of claim 11 , wherein the elongate puncture device delivers radiofrequency energy.

16 . The method of any one of claims 11 to 15 , wherein the elongate puncture device is a radiofrequency guidewire.

17 . The method of claim 11 , wherein EGMs are collected from a pericardium.

18 . The method of claim 11 , wherein EGMs are collected from a septum of a heart.

19 . The method of claim 11 or 17 , wherein the elongate puncture device applies pressure against pericardial tissue.

20 . The method of claim 11 or 18 , wherein the elongate puncture device applies pressure against a septum of a heart.

21 . A method of gaining access to a pericardial cavity comprising the steps of:

(a) introducing a blunt tipped stylet into an introducer;

(b) advancing the blunt tipped stylet and the introducer, in combination, through adipose tissue towards a tissue of the pericardium;

(c) removing the stylet from the introducer;

(d) installing an elongate puncture device, which is flexible, in the introducer;

(e) advancing the tip of the elongate puncture device to be distal of the introducer under fluoroscopy whereby an electrode of the elongate puncture device is in contact with a pericardium without any significant force being exerted;

(f) monitoring an EGM based on the electrode of the elongate puncture device which is in contact with the pericardium to confirm there is a low ST segment;

(g) exerting force with the introducer and the electrode of the guidewire to tent the pericardium;

(h) monitoring the EGM to confirm the wave is higher than the wave of step (f);

(i) delivered energy through the electrode to the tissue of the pericardium; and

(j) monitoring the EGM the ST segment is higher than the waves of steps (f) and (h).

22 . The method of claim 21 , wherein step (i) includes delivering a short pulse of high voltage AC.

23 . The method of claim 22 , wherein the short pulse is ⅓ second.

24 . The method of claim 21 , further comprising a step (k) of advancing the distal portion of the introducer into the pericardial cavity and monitoring the EGM.

25 . The method of claim 21 , wherein steps (e) and (f) are performed simultaneously.

26 . The method of claim 21 , wherein steps (g) and (h) are performed simultaneously.

27 . The method of claim 21 , wherein steps (i) and (j) are performed simultaneously.

28 . The method of claim 24 , further comprising a step (l) of delivering a contrast media.

29 . The method of claim 24 , further comprising a step (m) of withdrawing fluid from the pericardial space.

30 . The method of claim 24 , further comprising a step (n) of advancing a tip of the elongate puncture device into the pericardial cavity.

31 . The method of claim 24 , further comprising a step (n) of advancing the elongate puncture device into the pericardial cavity.

32 . The method of claim 31 , further comprising a step (o) of confirming access by wrapping the guidewire around the heart at least once and visualizing under fluoroscopy.

33 . A method of puncturing a target tissue to gain access to the pericardial cavity comprises the steps of:

(1) connecting an electrically insulated wire having one distal pole to a recording system that has an electrocardiographic reference to the patient;

(2) puncturing the patient's skin via the subxiphoid, parasternal intercostal or apical approach with a rigid introducer and an engaged stylet;

(3) advancing the rigid introducer and the stylet through various dermal layers and toward the pericardial sac of the heart under the guidance of fluoroscopy and tactile feedback to position the tip of the introducer near the pericardial sac;

(4) removing the stylet while a blunt radial tip of the introducer is docking with the pericardial sac, and installing the elongate puncture device in the introducer;

(5) advancing the elongate puncture device while the introducer is contacting the outside of the pericardial sac; and

(6) delivering energy to the pericardial sac through the electrode at the tip of Elongate puncture device.

34 . The method of claim 33 , wherein step (5) includes recording local epicardial EGMs from the electrode tip of the elongate puncture device.

35 . The method of claim 34 , wherein step (5) further comprises monitoring the EGM to confirm the amplitude of the waveforms increases with higher mechanical force against the heart.

36 . The method of claim 33 , wherein step (6) comprises the energy being delivered as at least one pulse.

37 . The method of claim 33 , wherein step (6) comprises the energy being delivered as a series of pulses, starting with a low pressure level against the pericardial sac in the first iteration to avoid overshoot, and the amount of pressure exerted on the pericardial sac is increased with each iteration while maintaining the same pulse time and energy level.

38 . The method of claim 33 , wherein step (6) comprises checking if the pericardial sac has been punctured and access to the pericardial cavity has been gained.

39 . The method of claim 33 , further comprising a step (7) of monitoring the electrical activity of the epicardial surface using the electrode on the distal tip of the elongate puncture device (after RF puncture of the pericardial sac provides access to the pericardial cavity).

40 . The method of claim 39 , further comprising a step (8) of deploying the elongate puncture device further into the pericardial space to relax pressure at the tip and cause a change in the EGM trace.

41 . The method of claim 40 , further comprising a step (9) of deploying the guidewire for tracking along the epicardial surface of the heart while collecting local epicardial EGM.

42 . The method of claim 40 , further comprising the step of advancing a sheath and dilator over the elongate puncture device.

43 . A method of confirming a position of a tip of an elongate puncture device relative to an introducer wherein the elongate puncture device has a proximal marker which is visible to a naked eye and a distal tip marker which is visible under an imaging system, and the introducer has distal end marker which is visible under the imaging system, the method including the steps of: (1) positioning the elongate puncture device relative to a proximal end of the introducer using the proximal marker without an imaging system; (2) turning on the imaging system; and (3) positioning a distal tip of the elongate puncture device relative to an end of introducer by viewing the distal tip marker and distal end marker using the imaging system.

44 . The method of claim 43 , wherein the imaging system is a fluoroscopy system and the distal tip marker and distal end marker are visible under fluoroscopy.

45 . An elongate puncture device comprising: a mandrel which is electrically conductive and covered by a clear layer of insulation, the clear layer stopping short of a distal end of the mandrel such that the distal end of the mandrel is electrically exposed to define a distal tip electrode, a portion of the mandrel being surrounded by a visible marker, the visible marker being covered by the clear layer, wherein the portions of the elongate puncture device at and adjacent the visible marker have a constant outer diameter.

46 . The elongate puncture device of claim 45 , wherein the mandrel is surrounded by an oxide coating which is covered by the clear layer of insulation, wherein for at least one portion of the mandrel the oxide coating has been removed such that said at least one portion defines at least one visible marker.

47 . The elongate puncture device of claim 46 , wherein the at least one visible marker comprises at least one portion of the mandrel wherein the oxide coating is in contact with the mandrel.

48 . The elongate puncture device of claim 45 , wherein the visible marker may be a proximal marker, an intermediate marker, or a distal marker.

49 . The elongate puncture device of claim 45 , wherein the clear layer comprises a heat-shrink layer.

50 . The elongate puncture device of claim 47 , wherein the heat-shrink layer comprises a polytetrafluoroethylene material.

51 . The elongate puncture device of claim 45 , wherein the mandrel is comprised of a nitinol.

52 . The elongate puncture device of claim 45 , wherein the mandrel is comprised of a stainless steel.

53 . The elongate puncture device of claim 46 , wherein the oxide coating is comprised of a layer of titanium dioxide.

54 . The elongate puncture device of any one of claims 45 to 53 , wherein the elongate puncture device is flexible.

55 . The elongate puncture device of any one of claims 45 to 53 , wherein the mandrel is electrically conductive, and a proximal end portion of the mandrel is uninsulated and operable for connecting to a power supply such that the distal tip electrode is in electrical communication with the power supply, and energy can be delivered through the distal tip electrode to tissue, and the distal tip electrode enables recording epicardial EGM.

56 . The elongate puncture device of claim 55 , wherein a shaft of the elongate puncture device is electrically insulated to reduce noise from any collected local EGM.

57 . The elongate puncture device of any one of claims 45 to 53 , wherein the distal tip electrode has a hemispherical dome with an outer diameter >0.027″ (0.686 mm) and a surface area of about 1.8 to about 2.4 mm 2 .

58 . The elongate puncture device of any one of claims 45 to 53 , further comprising a distal end portion which has a J-profile.

59 . The elongate puncture device of claim 58 , further comprising a radiopaque coil which extends around a curve of the distal end portion which has a J-profile.

60 . The elongate puncture device of claim 59 , wherein an end of the radiopaque coil can be used as a distal tip marker.

61 . The elongate puncture device of claim 59 , wherein the radiopaque coil has echogenic properties when using ultrasound to enable visualization of the guidewire tip.

62 . An introducer for use with an elongate puncture device, the introducer comprising an introducer shaft connected to a hub, the introducer shaft comprising an internal metal tube which is interposed between two layers of insulation with both ends of the two layers being joined together to bond the layers.

63 . The introducer of claim 62 , wherein the two layers of insulation are comprised of high-density polyethylene.

64 . The introducer of claim 62 or 63 , wherein the hub further comprise a male side port for connecting to tubing and a receiving opening for receiving a stylet or a wire whereby the hub is operable to be simultaneously attached to source of fluid while a stylet or a wire is inserted into the hub.

65 . A kit comprising an introducer and an elongate puncture device, the elongate puncture device including a distal tip electrode which enables recording epicardial EGM and a shaft of the elongate puncture device is electrically insulated to reduce noise in any collected local EGM; and

the introducer comprising an introducer shaft which connected to a hub, the introducer shaft comprising an internal metal tube which is interposed between two layers of electrical insulation with both ends of the two layers being joined together to bond the layers to reduce noise in any EGM collected by the elongate puncture device.

66 . The kit of claim 65 , wherein the introducer and the elongate puncture device are configured such that the introducer has the ability to deliver and withdraw fluid while the elongate puncture device is inserted therethrough.

67 . The kit of claim 66 , wherein the radial gap between an inner diameter of a tip of the introducer and outer diameter of the elongate puncture device is >0.025 mm (0.001″).

68 . The kit of claim 67 , wherein the kit is operable to provide contrast flow >15 ml/min at 69 Kilo Pascal (10 PSI).

69 . The kit of claim 67 , wherein the inner diameter of a tip of the introducer is 0.978 mm (0.0385 inches)+/−0.013 mm (0.0005 inches), and the maximum outer diameter of the elongate puncture device is 0.889 mm (0.0350 inches)+/−0.013 mm (0.0005 inches), whereby the minimum gap with this geometry is 0.032 mm (0.00125″).

70 . The kit of any one of claims 65 to 69 , further comprising a stylet wherein a cross section of the stylet varies along the length of the stylet, tapering down towards a distal tip of the stylet to allow a flow of a fluid through a tip of the introducer when the stylet is installed.

71 . The kit of any one of claims 65 to 69 , further comprising a stylet wherein the stylet is electrically insulated and operable to be connected to a recording system to facilitate collecting EGM information to help in positioning a tip of the introducer when approaching the heart.

72 . The kit of any one of claims 65 to 69 , further comprising markers for positioning the elongate puncture device relative to the introducer wherein the elongate puncture device has a proximal marker which is visible to a naked eye and a distal tip marker which is visible under an imaging system, and the introducer has distal end marker which is visible under the imaging system.

73 . The kit of claim 72 , wherein the distal tip marker and distal end marker are visible under fluoroscopy.

74 . The kit of claim 72 , wherein a tip of the elongate puncture device extends distal of a shaft of the introducer shaft when the proximal marker of the elongate puncture device is positioned at a proximal end of a hub of the introducer.

75 . The kit of claim 72 , wherein a tip of the elongate puncture device lines up with a distal end of a shaft of the introducer shaft when the proximal marker of the elongate puncture device is positioned at a proximal end of a hub of the introducer.

76 . The method of any one of claims 1 to 5 , 11 to 15 , 21 , 33 , and 43 , wherein the elongate puncture device comprises a radiofrequency guidewire.

77 . The elongate puncture device of any one of claims 45 to 53 , wherein the elongate puncture device comprises a radiofrequency guidewire.

78 . The kit of any one of claims 65 to 69 , wherein the elongate puncture device comprises a radiofrequency guidewire.