Connecting device for natural arteries with artificial arteries

The present invention discloses a connecting device to connect artificial arteries to normal arteries. The object of the invention is the prevention of obstruction of blood flow by hypertrophy of the inner lining of the artery commonly designated as the intima. The connecting device is placing the opening of the artificial artery inside of the natural artery beyond the level of the intima. This arrangement is preventing irritation of the intima of the natural artery by reducing turbulence of the boundary layer of the flowing blood. The connecting device can be manufactured as an integral part of the artificial artery or as a separate part to be connected to an artificial artery. The connecting device consists of a part penetrating the wall of the tapped natural artery and a sleeve to be attached to the outside of the natural artery. The sleeve itself is permanently attached to the connecting device. The distal part of the connecting device can be angled in order to facilitate the desired direction of the implanted artificial artery.

BACKGROUND--FIELD OF THE INVENTION 
This invention relates to the connection of artificial arteries or grafts 
to natural arteries, specifically the end to side connection whereby the 
end of the artificial artery is connected to the side of the natural 
artery. 
BACKGROUND OF THE INVENTION 
Vascular grafts and artificial arteries are well known in the art. See for 
example, U.S. Pat. No. 5,747,128 to Campbell, Chastain, Alvaro, and Pond; 
U.S. Pat. No. 5,716,395 to Myers and Lewis; U.S. Pat. No. 5,700,287 to 
Myers, Lewis, and Campbell; U.S. Pat. No. 5,609,624 to Kalis; U.S. Pat. 
No. 5,246,452 to Sinnott; and U.S. Pat. No. 4,955,899 to Della Corn, 
Farnan, Colone, and Kowligi. Artificial arteries are useful for bypassing 
obstructed natural arteries. All of these prior arts do not address the 
fact that the end to side connection of artificial arteries to natural 
arteries are subject to possible obstruction due to the hypertrophy of the 
intima caused by fluid dynamics in the region of the junction. 
The junction between natural artery and an artificial artery in side to end 
fashion is usually carried out in the following manner. For side to end 
connections, surgeons accomplish the junction of natural artery to 
artificial vessel by forming an opening in the natural artery to be 
fitting the proximal opening of an artificial vessel. Surgeons commonly 
connect artificial arteries to natural arteries by suturing the end of the 
wall of the artificial artery to the side of the wall of the natural 
artery. The differences of natural artery to artificial artery in their 
respective properties make it unavoidable that the dynamics of the blood 
flow constantly irritate the intima of the natural artery at the junction. 
The irritation is leading to hypertrophy of the arterial intima thereby 
narrowing the proximal orifice of the artificial vessel. At this junction 
the innermost layer of the natural artery, which is called "intima" in 
medical terms, is proliferating to such a degree that often blood flow 
into the artificial artery is diminished or cut off completely. Surgeons 
try to prolong the functioning of said junction by making the orifice of 
the junction as large as possible. In order to mitigate the problem 
surgeons prefer to connect the artificial artery at an angle. This 
approach is commonly called "fishmouthing". The connection of the 
artificial artery to the natural artery at an angle is providing a larger 
opening at the side of the natural artery and is, therefore, giving more 
space to the proliferating intima in order to prolong patency of the 
opening of the artificial artery. According to the authoritative textbook 
of Vascular Surgery 2nd Edition by Frank J. Veith, McGraw Hill 1994, 
Biologic and Prosthetic Materials for Vascular Conduits, Chapter 39, Page 
532, Line 49 (Exhibit 1), "small grafts fail at a rate approaching 100,000 
per year in the United States alone". Continuing on the same page, Line 
55, "the biology of the human endothelial cell and its role in maintaining 
blood fluidity remain major areas requiring investigation". 
The problem of "Neointimal Fibrous Hyperplasia: Pathogenesis and 
Prevention" is discussed in Critical Problems in Vascular Surgery, by 
Frank J. Veith, MD., printed by Appleton Century Crotts, New York, 1982 on 
Page 151 by James A. Deweese. On page 152, line 1 to 4, (Exhibit 2), "As 
long as the cause and the prevention of neointimal fibrous hyperplasia at 
anastomoses as well as along the entire graft surface remains 
undetermined, the search for the ideal vascular graft will continue." 
The surgical practice as described above does not take into account the 
mechanics of fluid dynamics, specifically micro whirls caused by the flow 
of blood, which is a suspension of microscopic particles in a viscous 
fluid. The present practice of anatomizing (connecting) of tubing with 
different mechanical properties is also neglecting the fact that the flow 
of any liquid, especially of a liquid with a considerable viscosity, is 
layered whereby the central core layer is moving at the fastest rate. The 
very purpose of the intima is to accommodate laminar flow. This pattern of 
flow is unduly disturbed by the usual side to end connection used 
presently in vascular surgery. The fluid dynamic forces unleashed by this 
technique have a negative effect on the intima at the site of the 
connection. The blood and the red blood cells in particular, due to their 
heavier specific weight, are scraping the intima sidewise and even hit it 
head on at the downstream end of the connection causing the intimate to 
proliferate and obstruct flow. 
There is thus a need for a connecting device which does not promote the 
obstruction of the blood flow into the artificial artery. 
SUMMARY OF THE INVENTION 
The object of the invention is the prevention of the hypertrophy of the 
intima usually seen at the surgical connection. This object can be 
achieved by diverting the flow of the blood from the inside of the natural 
artery. This can be accomplished by inserting part 1 of the connecting 
device (FIGS. 1 and 2) into the lumen of the natural artery through an 
incision into the wall of the artery. The insertion is done in such a 
fashion that the sleeve is touching the outside of the natural artery and 
is thereby determining the position of the orifice of the artificial 
artery within the flowing blood. The sleeve itself is sutured to the 
outside of the natural artery to be tapped. The use of this connecting 
device will prevent hypertrophy of the intima.

NUMBER LIST 
10 Connecting Device 
12 Top Section (penetrating the wall of the natural artery beyond the 
intima) 
14 Mid Section Sleeve 
16 Attachment of Sleeve 
18 Artificial Artery 
20 Holes (or tissue to be penetrated by a surgical needle) 
30 Natural Artery 
32 Wall of Natural Artery 
34 Inner Lining of the Natural Artery (commonly called the intima) 
36 Lumen of the Natural Artery 
40 Suture 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The object of the invention is the prevention of the obstruction of blood 
flow by hypertrophy of the inner lining of the artery commonly designated 
as the intima. This object can be achieved by diverting the flow of the 
blood from the inside of the natural artery. This can be accomplished by 
inserting part 1 of the connecting device (FIGS. 1 and 2) into the lumen 
of the natural artery through an incision into the wall of the artery. The 
insertion is done in such a fashion that the sleeve is touching the 
outside of the natural artery and is thereby determining the position of 
the orifice of the artificial artery within the flowing blood. The sleeve 
itself is sutured to the outside of the natural artery to be tapped. The 
use of this connecting device will prevent hypertrophy of the intima. The 
connecting device is placing the opening of the artificial artery inside 
of the natural artery beyond the level of the intima. This arrangement is 
preventing irritation of the intima of the natural artery by reducing 
turbulence. The connecting device consists of a part penetrating the wall 
of the tapped natural artery and a sleeve to be attached to the outside of 
the natural artery. 
The connecting device 10 can be manufactured as an integral part of the 
artificial artery or it can be produced separately in order to be 
connected to an artificial artery later. When the connecting device is 
made separately from the artificial artery there is a connecting 
arrangement between the connecting device and the artificial artery. Said 
connecting device 10 comprising a tube with an inlet opening (or receiving 
end) and an outlet opening and a sleeve positioned between said openings. 
The length of part 12 of the connecting device 10 should be long enough to 
reach through the natural artery wall 32 and into the lumen of the natural 
artery. (See FIGS. 1, 2, 4, and 5 part 12 and 12A.) 
The sleeve as seen in FIGS. 1, 2, 3, 4 and 5 as part 14 is adjacent to and 
attached to the wall of the natural artery 32 seen in FIG. 4. FIGS. 1, 2, 
3, and 4 show the sleeve itself is attached to part 18 by a reinforcing 
cuff part 16. FIG. 5 shows a possible variation that the attachment of the 
sleeve 16A is also providing a possible bend for the artificial artery 
18A. The inside diameter of the said connecting device 10 is determined by 
the amount of blood to be diverted and the size of the natural artery 30. 
The material of which the said connecting device 10 is made of can be hard, 
soft, flexible, or elastic. The material of which the sleeve is made out 
of should be of such a consistency as to be easily penetrated by a needle 
or staple yet be strong enough to hold the connecting device at the 
intended place or be made of a material that has holes 20 in the sleeve. 
The suture 40 attaches connecting device 10 to natural artery 30. 
Artificial artery 18 or attachment of sleeve 16A of the connecting device 
10 (FIG. 4 and 5) should be provided with curvatures of different degrees, 
mostly between 0 and 90 degrees, to give the surgeon using said connecting 
device 10 the opportunity to choose the most appropriate route for the 
artificial artery, for example parallel to the nonfunctional artery to be 
replaced. 
The distance between sleeve and curvature should allow the surgeon to 
complete the suturing or stapling process. It is evident that the consumer 
should be provided with connecting devices of different inside diameters 
and also with different curvatures and with proper interrelationship 
between diameters of the natural and artificial arteries and the flow rate 
of blood. The top section 12 always protrudes the intima 34 when 
connecting device 10 is attached properly.