Devices for accessing the pericardial space surrounding the heart

Abstract

Devices for accessing the pericardial space surrounding the heart. In at least one embodiment of a delivery catheter for use in accessing a pericardial space surrounding the external surface of a heart, the delivery catheter comprises comprising an elongated tube comprising a wall extending from a proximal end of the tube to a distal end of the tube, a first lumen, and a steering channel extending from a proximal end of the tube to a distal end of the tube, the steering channel forming an orifice at the distal end of the tube, and a steering wire system at least partially located in the steering channel, the steering wire system comprising at least two steering wires attached to the wall of the tube within the steering channel and a controller attached to a proximal end of each of the at least two steering wires, wherein the first lumen extends from approximately the proximal end of the tube to or near the distal end of the tube, the first lumen having a bend, relative to the tube, at or near the distal end of the tube and an outlet through the wall of the tube at or near the distal end of the tube.

Description

PRIORITY[0001]This U.S. continuation patent application is related to, and claims the priority benefit of, U.S. Nonprovisional patent application Ser. No. 12 / 596,964, filed Oct. 21, 2009, which is related to, claims the priority benefit of, and is a U.S. national stage application of, International Patent Application No. PCT / US2008 / 053061, filed on Feb. 5, 2008, which (i) claims priority to U.S. Provisional Patent Application Ser. No. 60 / 914,452, filed Apr. 27, 2007, and (ii) is related to, claims the priority benefit of, and in at least some designated countries should be considered a continuation-in-part application of, International Patent Application No. PCT / US2007 / 015207, filed Jun. 29, 2007, which is related to, and claims the priority benefit of, U.S. Provisional Patent Application Ser. No. 60 / 914,452, filed Apr. 27, 2007, and U.S. Provisional Patent Application Ser. No. 60 / 817,421, filed Jun. 30, 2006. The contents of each of these applications are hereby incorporated by ref...

AI Technical Summary

Problems solved by technology

However, endoluminal drug delivery has several shortcomings, such as: (1) inconsistent delivery, (2) low efficiency of localization, and (3) relatively rapid washout into the circulation.

Such patients generally have an abnormality in conduction that causes the right and left ventricles to beat (i.e., begin systole) at slightly different times, which further decreases the heart's already-limited function.

Like the local delivery of drugs to the heart, the placement of CRT leads on the heart can be challenging, particularly when the target placement site is the left ventricle.

Problems with these methods of lead placement can include placement at an improper location (including inadvertent placement at or near scar tissue, which does not respond to the electrical signals), dissection or perforation of the coronary sinus or cardiac vein during placement, extended fluoroscopic exposure (and the associated radiation risks) during placement, dislodgement of the lead after placement, and long and unpredictable times required for placement (ranging from about 30 minutes to several hours).

The additional clearance tends to decrease the likelihood that the myocardium will be inadvertently punctured when the pericardial sac is pierced.

Although this technique works well in the normal heart, there are major limitations in diseased or dilated hearts—the very hearts for which drug delivery and CRT lead placement are most needed.

When the heart is enlarged, the pericardial space is significantly smaller and the risk of puncturing the right ventricle or other cardiac structures is increased.

Additionally, because the pericardium is a very stiff membrane, the suction on the pericardium provides little deformation of the pericardium and, therefore, very little clearance of the pericardium from the heart.

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