Method for cardiac restraint
View Patent ↗Apparatus and methods for using the apparatus are disclosed for cardiac restraint. More specifically, the apparatus and methods are directed to accessing the pericardium, accessing the heart within the pericardium, and restraining the heart by at least partially enclosing the heart with the apparatus. An embodiment of a cardiac restraint apparatus according to the present invention comprises a jacket, the jacket having a rim which defines an opening for receiving a heart. The apparatus also comprises a knot pusher that has a hollow elongate body, as well as a strand that extends around the rim of the jacket and is tied into a slipknot. The strand is positioned such that at least one end portion of the strand extends through the knot pusher such that a distal end of the knot pusher can be moved into engagement with the slipknot, whereby pulling the end portion of the strand away from the heart while pushing the knot pusher against the slipknot and reducing the diameter of the opening defined by the rim. In addition, the apparatus comprises one or more guide elements that are attached to the jacket.
1. A method for constraining expansion of the heart comprising the steps for:
forming a subxiphoid entry incision;
introducing through the subxiphoid entry incision an endoscopic cannula having at least one lumen extending therethrough;
advancing the endoscopic cannula toward the pericardium;
introducing through a lumen of the endoscopic cannula a pericardial entry instrument to form an aperture near the apical pericardium into the intrapericardial space about the heart;
advancing the endoscopic cannula through the aperture;
introducing cardiac restraint apparatus through a lumen of the endoscopic cannula into engagement with the heart; and
manipulating the cardiac restraint apparatus within the intrapericardial space into substantially surrounding engagement about at least a portion of the heart.
2. The method according to claim 1 in which advancing the endoscopic cannula includes dissecting the linea alba and forming a passage posterior to the sternum toward the apex of the heart.
3. The method according to claim 1 in which introducing the cardiac restraint apparatus includes configuring the cardiac restraint apparatus within a volume dimensioned to pass through a lumen within the endoscopic cannula and through the pericardial aperture into the intrapericardial space about the heart.
4. The method according to claim 3 in which manipulating the cardiac restraint apparatus includes expanding within the intrapericardial space the cardiac restraint apparatus from the confined configuration thereof for positioning the unconfined cardiac restraint apparatus about a portion of the heart within the intrapericardial space.
5. The method according to claim 4 in which the cardiac restraint apparatus includes a jacket having a rim defining an opening for receiving a heart and including attached to the rim at least one guide handle of sufficient length to extend from the heart out through the subxiphoid entry incision, the jacket and rim and guide handle being configured within the dimension to pass through a lumen of the endoscopic cannula, and the method further comprising the step for:
positioning the rim of the jacket substantially about the heart within the intrapericardial space in response to manual manipulation of the guide handle from outside the subxiphoid entry incision.
6. The method according to claim 5 further comprising the steps for:
selectively tightening the rim about the heart; and
detaching the guide handle from the rim for removal of the guide handle through the lumen of the endoscopic cannula.
7. The method according to claim 4 in which the cardiac restraint apparatus includes an elastic band for encircling the heart, the method further comprising the steps for:
introducing the elastic band through the lumen of the endoscopic cannula into the intrapericardial space; and
positing the elastic band substantially encircling the heart.