Surgery – Instruments – Surgical mesh – connector – clip – clamp or band
Reexamination Certificate
2000-09-01
2004-11-02
Woo, Julian W. (Department: 3731)
Surgery
Instruments
Surgical mesh, connector, clip, clamp or band
C606S151000, C606S213000, C606S219000
Reexamination Certificate
active
06811555
ABSTRACT:
TECHNICAL FIELD OF THE INVENTION
The present invention relates to the art of surgery. More specifically, it relates to the field of apparatus and methods for performing anastomosis without hand-suturing.
BACKGROUND OF THE INVENTION
In the United States, many coronary artery bypass graft (CABG) procedures performed on patients annually. Each of these procedures may include one or more graft vessels which are hand sutured. Until recently, coronary artery bypass procedures have been performed with the patients on cardiopulmonary bypass while the heart is stopped with cardioplegia and the surgery is performed on an exposed, stationary heart.
The vast majority of CABG procedures performed currently are accomplished by opening the chest wall to gain access to the coronary vessels. Through the use of heart lung bypass machines and a drug to protect the heart muscle, the heart is stopped and remains still during the procedure. In this setting, the surgeon has ample time and access to the vessels to manipulate hand suturing instruments such as forceps, needle holders and retractors.
However, with increasing costs of hospital stays and increased awareness by patients of other minimally invasive surgical procedures, interest in developing a minimally invasive CABG procedure is increasing. Hospitals need to reduce costs of procedures and patients would like less post-operative pain and speedier recovery times.
With an increased incentive to reduce costs, there is a renewed interest in redesigning cardiothoracic procedures. A few pioneering surgeons are now performing minimally invasive procedures whereby the coronary artery bypass is performed through a small incision in the chest wall. There are some surgeons that believe that the best way to perform a minimally invasive coronary artery bypass procedure is to perform the procedure on a beating heart, i.e., without heart-lung bypass and cardioplegia. This minimizes the time it takes to perform the procedure and reduces the cost of the operation by eliminating the heart lung bypass machine.
In the case of minimally invasive procedures on a beating heart, the surgeon starts by making a mini-thoracotomy between the fourth and fifth ribs and, sometimes, removing the sternal cartilage between the fourth or fifth rib and the sternum. The space between the fourth and fifth ribs is then spread to gain access to the internal mammary artery (IMA) which is dissected from the wall of the chest. After dissection, it is used as the blood supply graft to the left anterior descending artery of the heart (LAD). Below the IMA lies the pericardium and the heart. The pericardium is opened exposing the heart. At this point, the LAD may be dissected from the fissure of the heart and suspended up with soft ligatures to isolate the artery from the beating heart. Typically, a special retractor gently applies pressure to the heart muscle to damp movement at the LAD. A small arteriotomy is performed in the LAD and the graft IMA is sutured to the LAD.
Traditionally, to gain access to the cardiac vessels to perform this procedure the sternum is sawn in half and the chest wall is separated. Although this procedure is well perfected the patient suffers intense pain and a long recovery.
Until recently all bypass graft procedures have been performed by hand suturing the tiny vessels together with extremely fine sutures under magnification. The skills and instruments required to sew extremely thin fragile vessel walls together have been perfected over the last twenty years and are well known to the surgical community that performs these procedures.
FIG. 1
shows a conventional anastomosis using hand-sutures, in which coronary artery
10
and graft vessel
12
are connected in side-to-side fashion One end (
13
) of vessel
12
is tied closed, and the side wall of vessel
12
near this closed end is to be attached to artery
10
. The opposite end of vessel
12
(not shown) is to be attached to an aorta or IMA. In typical cardiopulmonary bypass procedures, one end of a graft vessel is grafted to a coronary artery (at a “distal” graft site) and the other end of the graft vessel is grafted to the aorta (at a “proximal” graft site).
FIG. 1
shows a distal graft site. An incision
14
is made in artery
10
and a corresponding incision
16
is made in graft
12
. The surgeon aligns the incisions and hand-sutures the aligned edges of the incisions together using sutures
18
and
20
. Hand-suturing can also be used to perform an end-to-side anastomosis, in which an open end of the graft vessel is aligned with an incision in the sidewall of another vessel (e.g., an aorta) and the aligned tissue is hand-sutured together. The present invention can be used to perform either end-to-side or side-to-side anastomosis without hand-suturing.
There is a need (which is addressed by the present invention) for methods and apparatus useful for performing anastomosis during CABG surgery on a beating heart. When performing anastomosis during such surgery on a beating heart, use of hand-suturing to attach the graft vessel is very imprecise due to the translation of movement from the beating heart to the suspended artery. This motion may cause imprecise placement of the suture needles. Any imprecise placement of the sutures may cause a distortion of the anastomosis which may cause stenosis at this junction. The sutures used for this procedure are extremely fine (0.00” in diameter) and are placed less than 1 mm apart.
As one can imagine it is difficult enough to place suture needles the size of a small eyelash into a vessel wall with placement accuracy of better than 1 mm. To accomplish this feat of precision on a moving target is extremely difficult. To make matters worse, the site is often bloody due to the fact that the heart has not been stopped. During beating heart surgery, the surgeon can attempt to minimize the deleterious effects of the beating heart motion by using suspension or retraction techniques, but it is impossible to isolate all such movement (and attempts to minimize the motion can damage the vessel being restrained or cause myocardial injury). Even when performing anastomosis in an ‘open chest’ surgical setting in which the surgeon has adequate access and vision of the surgical site to manipulate the anatomy and instruments, it is difficult to perform the hand-suturing required in traditional methods. When performing anastomosis in a minimally invasive procedure, access to (and vision of) the site is more limited and the hand-suturing is more difficult.
If the sutures are not placed correctly in the vessel walls, bunching or leaks will occur. During a minimally invasive procedure this is disastrous, usually resulting in the conversion to an open chest procedure to correct the mistake. Any rough handling of the vessel walls is detrimental as inflammation can cause further postoperative complications.
An anastomosis must seal without leaking to prevent exsanguination. Therefore, any anastomosis technique which does not require hand sutures must provide a leak free seal in a very confined space, while providing proper flow area in the vessel after healing is complete.
Although minimally invasive CABG procedures are taking place now with hand-sutured anastomosis they require superlative surgical skills and are therefore not widely practiced. There is a need for methods and apparatus which permit the forming of a precise anastomosis without requiring the stopping of a beating heart, during either minimally invasive or open chest surgery, and without requiring hand suturing.
Several techniques have been proposed for performing anastomosis of blood vessels. However, the prior art techniques often require the vessels to be severely deformed during the procedure. The deformation may be required to fit the vessels together or to fit a vessel to an anchoring device.
For example, some prior art anastomosis techniques have used rigid rings to join two vessels together. In one such technique (indicated by FIG.
2
), rigid ring
30
′ is positioned around the edges of an incision in the
Blackwood Bradley D.
Callas Peter
Christakis George T.
Davis John W.
Knight Andrew
Law Office of Alan W. Cannon
Origin Medsystems Inc.
Woo Julian W.
LandOfFree
Method and apparatus for performing anastomosis with... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for performing anastomosis with..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for performing anastomosis with... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3312796