A comparison of absorbable suture and argon laser welding for lateral repair of arteries.

Conventional vascular anastomoses between autogenous vessels are performed with nonabsorbable sutures. Recently, use of absorbable sutures and laser-assisted vascular anastomoses has been advocated because of their improved healing characteristics. This study compared arterial repairs with the argon laser, absorbable suture, and nonabsorbable suture for technical characteristics including additional suture and overall success rates, burst strength, and cost. Absorbable and nonabsorbable suture closures were comparable with respect to technique, but laser-assisted vascular anastomosis was technically more demanding and required almost twice as much time for completion. The argon laser successfully closed only 58.6% of the arteriotomies, and 90% of the closures required additional sutures for complete hemostasis. All sutured arteriotomies were successfully completed by use of either absorbable or nonabsorbable suture. Burst strength was similar for all groups, but was uniformly greater than 300 mm Hg for sutured repairs, whereas two of five laser-assisted closures burst below 300 mm Hg. Finally, costs for purchasing ($35,000) and operating ($300/hr.) an argon laser make laser-assisted vascular anastomosis much more expensive than sutured repair. These data suggest argon laser-assisted vascular anastomoses are more technically demanding, less successful, and more expensive than conventional sutured anastomoses when evaluated in large caliber arteries in a canine model. Absorbable suture, however, is comparable to conventional nonabsorbable sutured arterial repairs in expense, handling characteristics, and success rates with the added advantage of eliminating permanent foreign body in the arterial wall when it is absorbed.     

A comparison of CO2 laser-assisted venous anastomoses and conventional suture techniques: patency, aneurysm formation, and histologic differences

The expected patency and the potential complications of CO2 laser-welded end-to-end venous anastomoses have not been well established despite increasing clinical interest in the subject. To further study this relatively new technique we used the internal jugular veins (1.0 to 1.4 mm diameter) of 15 New Zealand White rabbits weighing 2.5 to 3.5 kg. On one randomly selected side, a laser-welded end-to-end anastomosis was performed in all animals by placing three equidistant stay sutures followed by welding the vein edges with a CO2 laser (spot size of 0.27 mm, power of 100 mW, and power density of 175 W/cm2). On the contralateral side, the vein was anastomosed with interrupted 10-0 nylon sutures in 10 animals, and in the remaining five animals a continuous 10-0 nylon suture technique was used. All anastomoses were surgically assessed at 30 days after operation. A significantly lower 30-day patency rate (p less than 0.05, Fisher's Exact Test) was found in anastomoses constructed by use of the continuous technique (20%) compared with either interrupted (90%) or the laser-assisted technique (87%). No significant difference was observed in 30-day patency between laser-assisted and conventional interrupted anastomoses. Anastomoses performed with the continuous and the laser-assisted technique required 12.5 +/- 1.3 and 12.9 +/- 3.0 minutes, respectively, whereas those constructed with interrupted technique required 19.1 +/- 4.5 minutes (p less than 0.05, Student-Neuman-Keuls' Test). No evidence of false or true aneurysm was noted in any of the animals. Histologic evaluation of laser-assisted anastomoses demonstrated early full-thickness coagulation necrosis of the wall with reendothelialization by 7 days and complete healing by 30 days after the procedure. Conventional anastomoses showed reendothelialization and minimal necrosis near the sutures at 7 days, but healing was complete by 30 days after the procedure. The patency rate of vein anastomoses performed with the CO2 laser is excellent and superior to the one obtained with continuous sutures, and except for less operating time, the former technique does not appear to offer any significant advantage over the conventional interrupted suture technique for small vein anastomosis in this animal model up to 1 month of follow-up.     

Laser-assisted microvascular anastomoses: angiographic and anatomopathologic studies on growing microvascular anastomoses: preliminary report

A low-powered carbon dioxide laser was used to perform end-to-end anastomoses of growing femoral arteries (mean diameter 1.6 mm) in miniature swine. Five microvascular conventional anastomoses were performed with 10-0 monofilament interrupted sutures. Nine laser-assisted vascular anastomoses were performed. The mean duration of each anastomosis was 30 +/- 3 minutes for the conventional anastomosis and 20 +/- 2 minutes for the laser-assisted vascular anastomosis (p less than 0.05). All anastomoses were patent at the completion of the procedure. Each laser-assisted anastomosis required an average of eight laser pulses of 2 to 4 seconds. After 13 weeks the external diameters of the conventional anastomoses were 1.8 mm (+15%), while the laser-assisted anastomoses averaged 3.0 mm (+81%) (p less than 0.05). All nine laser-assisted anastomoses were patent, functional, and free of stenosis compared with one out of five conventional anastomoses. Histologically the laser induced minimal or no fibrosis, allowing normal physiologic healing and growth patterns. Electron microscopy confirmed that the integrity of the arterial layers had been restored. These findings suggest that a low-energy carbon dioxide laser has potential clinical application for anastomosis of small growing vessels.     

Low power CO2 laser-assisted microvascular anastomosis: an experimental study

Low power CO2 laser-assisted microvascular anastomosis (LAMA) was used for saphenous artery autotransplantation in 40 rabbits. Eighty end-to-end anastomoses were performed by three methods (conventional interrupted suture, stay suture + laser, laser without stay suture). The long term patency rate in the three types of anastomosis is 93%, 93%, and 100%, respectively. The time needed for the laser procedure is half to one-third of that required for the interrupted suture method. The tensile strength of the bonding site can withstand up to 250 mm Hg of arterial pressure. We have demonstrated that the CO2 laser can be used in microvascular anastomosis with or without stay sutures. Aneurysm formation is a potential risk of LAMA. Accurate coaptation of the transected vessel, precise control of laser energy, and minimal area exposed to the laser beam are the key points for further improving anastomotic quality.     

A comparison of para-anastomotic compliance profiles after vascular anastomosis: nonpenetrating clips versus standard sutures

PURPOSE: Anastomotic compliance is an important predictive factor for long-term patency of small diameter vascular reconstruction. In this experimental study we compare the compliance of continuous and interrupted sutured vascular anastomoses with those using nonpenetrating clips. METHODS: Both common carotid arteries in nine goats (average weight, 57 +/- 5.7 kg) were transected, and end-to-end anastomoses were constructed with nonpenetrating clips or polypropylene sutures. The latter were applied with both interrupted and continuous techniques. Intraluminal pressure was measured with a Millar Mikro-tip transducer, and vessel wall motion was determined with duplex ultrasound equipped with an echo-locked wall-tracking system. Diametrical compliance was determined. Environmental scanning electron microscopy was performed on explanted anastomoses. RESULTS: There was a reduction in anastomotic compliance and associated proximal and distal para-anastomotic hypercompliant zones with the use of all techniques. However, compliance loss was significantly less in those anastomoses with clips and interrupted sutures when compared with continuous suture (P <.001). Furthermore, the total compliance mismatch across anastomoses with continuous sutures was significantly greater than those with clips or interrupted sutures (P <.05). The mean time for constructing clipped anastomoses was 5.7 +/- 1.4 minutes, which was significantly less than either continuous (P <.0001) or interrupted sutures (P <.0001). Furthermore, environmental scanning electron microscopy demonstrated minimal intimal damage with good intimal apposition in the clip group. CONCLUSION: Anastomoses performed with nonpenetrating clips resulted in improved para-anastomotic compliance profiles and reduced intimal damage when compared with those with polypropylene sutures. These benefits may enhance long-term graft patency by reducing the risk of anastomotic intimal hyperplasia.     

Experimental and early clinical evaluation of vascular anastomoses with argon laser fusion and the use of absorbable guy sutures: a preliminary report

This study investigated the feasibility of forming vascular anastomoses by use of argon laser tissue fusion and absorbable, monofilament polydimethylsiloxane guy sutures. In initial animal studies femoral arteriovenous fistulas approximately 1.5 cm in length were created bilaterally in each of 10 dogs and were studied histologically at 2, 4, 8, 16, and 24 weeks (two animals in each interval). In each animal, one anastomosis (control) was formed with continuous 6-0 polypropylene suture, and the contralateral anastomosis (experimental) was performed with an argon laser (0.5 watt, 5 to 7 minutes exposure, energy fluence 1100 to 1500 joules/cm2 per 1 cm length) with stay sutures of 5-0 polydimethylsiloxane at 0.5 to 0.65 cm intervals. At removal, all anastomoses were patent without hematomas, aneurysms, or luminal narrowing. Histologic examination at 2 to 16 weeks demonstrated resorption of the biodegradable suture material by a local inflammatory reaction. By 24 weeks, laser-fused specimens had no evidence of suture material at the anastomotic line, and healing consisted of a bond between artery and vein wall tissues. Control suture specimens at the same intervals exhibited an organized fibrous tissue response to the suture. Clinical adaptability of this technology has subsequently been evaluated in five patients at 10 to 27 months (21.6 +/- 5.8) by physical examination and duplex scanning and demonstrate no evidence of abnormal healing. This study establishes the experimental and preliminary clinical feasibility of laser-fused anastomoses aligned by biodegradable guy sutures and supports further investigation and refinement of the technique.     

Initial human evaluation of argon laser-assisted vascular anastomoses

Forearm Brescia-Cimino arteriovenous fistulas were chosen for the initial clinical evaluation of argon laser-assisted anastomosis of human vessels. Ten patients with chronic renal failure had side-to-side radial artery/cephalic vein fistulas fused by laser. Incisions 1.2 to 1.5 cm in length were made in adjacent segments of artery and vein and were aligned for application of laser energy by four 6-0 polypropylene sutures. The sutures divided each fistula into four segments that were 5.0 to 6.5 mm long. Each segment was sealed satisfactorily in 75 to 100 seconds by use of 0.5 W, 1130 to 1520 joule/cm2 argon laser energy fluence. Seven (17.5%) of 40 bonds required an additional 7-0 biodegradable suture to close small gaps that did not fuse adequately. Serial prospective follow-up studies of the patients by physical examination and duplex scanning for periods of 12 to 20 months (15.4 +/- 2.8, n = 7) postoperatively have shown uniformly patent, compliant anastomoses with no evidence of hematomas, false aneurysms, or luminal narrowing. Histologic examination of two patent fistulas that were excised during revision procedures at 4 and 5 months postoperatively showed healing of the entire circumference of the anastomosis similar to that noted in extensive preclinical canine studies. We conclude from these preliminary results that argon laser vascular tissue fusion is possible in humans when reliable primary sealing of vascular anastomoses is achieved, and that healing occurs without aneurysmal dilatation during follow-up of up to 20 months.     

Comparison of nylon and polypropylene sutures in a microvenous thrombosis model

Thrombosis rates of femoral end-to-end microvenous anastomoses with nylon and polypropylene sutures (9–0 suture, 70 μ needle) were compared in a microvenous thrombosis model. The vessel injuries were produced during anastomosis by using a suture with a knot 1 cm from the needle. Anastomotic thrombosis rates were assessed by visual inspection and strip test at 24 hr postoperatively. Low thrombosis rates (0% and 20%, respectively) of anastomoses with both unknotted nylon and unknotted polypropylene sutures were obtained. Anastomoses with knotted nylon and polypropylene sutures resulted in 65% and 45% thrombosis rates, respectively. Statistical analyses showed that there were no significant differences between thrombosis rates, both in anastomosis performance with unknotted nylon and polypropylene sutures (P > 0.05) and with knotted nylon and polypropylene sutures (P > 0.05), while there were significant differences between the thrombosis rate using unknotted sutures and knotted sutures (P<0.01). It was concluded that vascular injury, not suture material, is the main factor leading to thrombosis in this model. © 1995 Wiley-Liss, Inc.     

A comparison of interrupted and continuous sutures for tracheal anastomoses in sheep.

OBJECTIVE: To study the tensile strength of tracheal anastomoses. DESIGN: Experimental study. SETTING: University medical school laboratory, Germany. ANIMALS: 15 sheep. INTERVENTIONS: Tracheal anastomoses with three different suturing techniques: a continuous suture and interrupted sutures with either a monofilament or a polyfilament material. Anastomoses were tested to breaking after being in place for 1, 2, 4, 8 or 24 weeks. RESULTS: After one week, with all three materials, the trachea broke at the anastomosis. In animals that survived longer, the trachea broke further away from the anastomosis. There was no significant difference between the mean values of the breaking force for continuous sutures and single interrupted sutures (p = 0.9). CONCLUSION: The suturing technique (continuous or interrupted) has less relevance for the tensile strength of the anastomosis than in vitro experiments suggest.     

Minimally occlusive laser vascular anastomosis (MOLVA): experimental study

Background  Temporary occlusion of an intracranial artery during microvascular anastomosis is a major risk factor in cerebrovascular surgery. A new laser vascular welding technique that minimizes the occlusion time of the recipient vessel has been developed and is described in this report. Method  A new minimally occlusive technique of end-to-side microvascular anastomosis was developed employing a diode laser in association with the application of a chromophore in our experimental model of double end-to-side anastomosis. The implantation of a vein graft on the patent carotid artery was obtained through the application of three interrupted sutures at each anastomotic site; the carotid was then clamped, two arteriotomies were performed, followed by the application of a fourth suture and of the laser welding procedure on each anastomosis. Monitoring of the temperature at the site of the anastomosis was introduced in order to control the welding technique. Findings  The time of the clamping of the carotid artery was 12 min to perform two end-to-side anastomoses (i.e., 6 min for each anastomosis). All bypasses were patent after a follow-up of 90 days and histological study confirmed good preservation of the vascular wall. Conclusions  Our laser-assisted technique of vascular anastomosis reduces the duration of the clamping of the recipient artery down to 6 min. This technique can minimize the risk of cerebral ischemia associated with occlusion of a recipient artery in intracranial bypass procedures, promoting an improved vascular healing process with a lower risk of thrombosis and occlusion.     

Growth of the aortic anastomosis in puppies--comparison of monofilament suture materials, whether absorbable or nonabsorbable, and of suture techniques, whether continuous or interrupted

This study compared the growth of vascular anastomoses performed with either polypropylene or polydioxanone sutures and with either continuous running suture or interrupted suture technique. Primary end-to-end anastomoses of the infrarenal aorta were performed in 38 puppies. Nineteen were performed with 5-0 polypropylene sutures; in ten all sutures were placed in continuous fashion, and in nine in interrupted fashion. The other nineteen were performed with 5-0 polydioxanone sutures; in ten the sutures were placed in continuous fashion, and in nine in interrupted fashion. The animals were subjected to the repeated aortograms at 2, 4, 8 weeks, 6 months and 1 year following operation. Each abdominal aorta was subjected to burst test, and pathological examination. All anastomoses were patent and tolerated burst-test (300 mmHg). Neither aneurysm nor dilatation of anastomotic site was observed. Anastomotic area was significantly smaller and more stenotic in the continuous polypropylene suture group than in other three groups at 8 weeks, 6 months and 1 year following operation. There was no significant difference among these three groups. No suture materials were observed in the polydioxanone suture groups after 6 months following operation. This study suggests that polydioxanone suture will be useful for the repair of cardiovascular anomalies where growth of the suture line is required.     

Laser-assisted microsurgical anastomosis

A low power carbon dioxide laser was used to perform 212 end-to-end laser-assisted microvascular anastomoses (LAMA) of femoral arteries (mean diameter, 1.2 mm) in Sprague-Dawley rats. Eighty-two conventional microvascular suture anastomoses (CMSA) utilizing 10-0 monofilament interrupted sutures were done for comparison of techniques and wound healing. The mean duration of each anastomosis procedure was 16 minutes for the LAMA repairs, compared to an average of 27 minutes for the CMSA repairs (P less than 0.05). All anastomoses were patent at the completion of the procedure. Each laser-assisted anastomosis required an average of seven intermittent laser exposures of 0.1 to 0.3 seconds each with approximately 80 mW of CO2 (wavelength = 10.6 micron) radiation at a spot size of 150 micron. A patency rate of 95% was obtained on the LAMA vessels (202 of 212) compared to 96% for the CMSA repairs (79 of 82). A total of 14 aneurysms were noted in the LAMA group (7%) compared to 11 in the CMSA (13%). All aneurysms were in patent vessels. Histological analysis indicates that the progression of wound healing of LAMA and CMSA anastomoses follows similar paths chronologically and morphologically with increased scar tissue formation around the suture. Scanning electron microscopy confirms the comparable luminal healing of the LAMA and CMSA vessels, with complete reendothelialization occurring by 3 weeks postoperatively. The tensile strength of the LAMA repair, although low immediately after operation, is comparable to that of the intact artery at 21 days. These findings suggest that a low energy carbon dioxide microsurgical laser has potential beneficial clinical application for anastomosis of small vessels.     

Scanning Electron Microscopic Evaluation of Nonocclusive Excimer Laser-Assisted Anastomosis in Rabbits

Summary  Background. The nonocclusive Excimer laser-assisted bypass technique has been described in previous studies and proved to be a promising bypass operation in vascular brain surgery. Little is known about the morphological regeneration process of the laser-assisted anastomosis in time.  By way of a scanning electron microscopic study we examined the way in which the anastomosis site created by the nonocclusive Excimer laser-assisted anastomosis technique becomes endothelialized.  Methods. In 14 rabbits the internal jugular vein was placed in a loop on the abdominal aorta. The distal anastomosis was made using the nonocclusive Excimer laser-assisted technique. The proximal anastomosis was made either laser-assisted or conventional end-to-side. After clipping of the aorta between the two anastomoses sites the vein served as a bypass. To evaluate the endothelialization at the laser-assisted anastomosis site in time, a scanning electron microscopic study was performed.  Results. In the first hours after the bypass operation a new intimal surface is formed by fibrin and activated platelets. Some leukocytes are seen during the first days. The endothelialization process of the laser-assisted anastomosis site begins one day after the operation. The gradual endothelialization process evolved along two lines. First, endothelial cells grow from the side of the aorta to the bypass. Second, after one day solitary (blood-borne) endothelial cells deposit on the laser edge and the sutures, covering the platelet aggregates.  Conclusions. The endothelialization of the Excimer laser-assisted anastomosis is more or less completed 9 days after the operation. The edge created by the laser becomes smoother after a few days and is gone for the most part after 9 days.     

Fibrin glue application in microvascular anastomosis: comparative study of two free flaps series

Background: Since the first experiments with fibrin glue application in microvascular anastomoses in 1977, several studies have reported its benefits on suture reduction and anastomosis decreased time. In spite of that, clinical experience has been limited to two neurosurgical and two replantation case series, all of them with good results. This study was conducted to evaluate the feasibility and the potential benefits of fibrin glue application in free flaps. Methods: We performed 24 free flaps in 24 patients, from March 2005 to June 2006. Twenty were included in this study. They were divided into two groups according to the anastomosis technique: conventional group (n = 7 patients) and fibrin glue group (n = 13 patients). In the conventional group, the anastomosis was performed with interrupted sutures, whereas in the fibrin glue group, they were performed using less sutures and fibrin glue application. Results: The application of fibrin glue cut by half the number of sutures required to complete the anastomoses. The mean arterial and venous anastomotic times in the conventional group were 27.2 and 24.0 minutes, respectively. In the fibrin glue group, they were 13.6 and 12.6 minutes, respectively. All these differences were statistically significant. There was no significant difference of ischemic time between two groups (P = 0.26). The survival rate of the flaps was similar in both groups: 84.6% (11 of 13) in the fibrin glue group and 85.7% (6 of 7) in the conventional group (P = 1.0). Conclusions: Fibrin glue application in free flaps was feasible and allowed us to complete the anastomoses with fewer sutures and less time. The survival rate of the flaps was not adversely affected by the fibrin glue. © 2008 Wiley‐Liss, Inc. Microsurgery, 2009.     

Polydioxanone suture material in growing vascular anastomoses. Experimental study

We studied the growth of vascular anastomoses after use of absorbable suture material in 21 piglets. In six piglets, end-to-end anastomosis of the infrarenal aorta was performed with 5-0 continuous polypropylene suture; stenosis developed in two of these animals. In 15 piglets, continuous polydioxanone sutures were used for the anastomoses, and no stenosis developed. On the contrary, 14 of these anastomoses showed some degree of dilation at the anastomotic site. Burst testing to 300 mm Hg caused no disruption. On histologic examination, only scar tissue at media and intima with good degree of differentiation was noted. Growth of a vascular anastomosis after use of absorbable polydioxanone suture material seems to be perfectly possible without stricture formation. Because the growing process takes years instead of months in human beings, with obviously less stress at the anastomotic site, it is likely that dilatation at the level of the suture line will not occur in clinical use.     

An alternative method of vascular anastomosis by laser: experimental and clinical study

In vascular surgery, it is now very difficult to maintain the long-term patency after a conventional vascular anastomosis, especially for small-caliber vessels. A low-energy CO2 laser was experimentally employed to make a vascular anastomosis with only a few sutures. Subsequently, it could be confirmed that optimal conditions for vascular anastomosis by laser were 20-40 mW in output and 6-12 sec/mm in irradiation time. On the other hand, pressure tolerance test as well as tensile strength test and microscopic examinations at the sites of anastomoses by laser were compared with the conventional suture method. There were no significant differences between laser and suture methods. On the basis of the excellent results of this study, the laser was clinically applied for anastomoses of the peripheral vessels in 35 patients. The first clinical laser application in the world was successful in a 44-year-old female patient with chronic renal failure in 1985. All patients are doing well without any complications from vascular anastomosis by laser. From these experimental and clinical studies, it can be concluded that anastomosis by laser should be recommended for small-caliber vessels such as aortocoronary bypass surgery.     

Laser-assisted vasal anastomosis in the rat and man

In order to study the efficacy of laser-assisted vasal anastomosis (LAVA), a microscopic carbon dioxide surgical laser (Xanar) was utilized in the anastomoses of human vas deferens in vitro and the Sprague-Dawley rat vas deferens in vivo. The longitudinal tensile and internal hydrostatic pressure strengths of laser-assisted vasal anastomoses were compared to conventional microsurgical suture anastomoses in the human vas deferens. The LAVA group had a greater mean internal hydrostatic pressure strength (p less than 0.001) and a lesser mean longitudinal tensile strength (p less than 0.001) than the conventional microsurgical group. Further evaluation was performed in the Sprague-Dawley rat model, comparing post-operative fertility, patency, healing and sperm granuloma occurrence among four surgically treated groups and a control group: LAVA, conventional suture anastomosis, sham operated, and vasectomized. Light and scanning electron microscopic examination revealed equivalent healing in both the LAVA and conventional groups. Fertility was not statistically different in the LAVA, conventional, control, and sham operated groups. However, the incidence of gross sperm granulomas observed in the LAVA group (80%) was much higher than in the conventional suture anastomosis group (0%). In conclusion, laser-assisted vasal anastomosis is a fast and simple technique for vasal reanastomosis and was as successful (in pregnancies) as conventional suture anastomosis in producing fertility in rats undergoing vasal reanastomosis, but the incidence of sperm granuloma is higher.     

End-to-side and end-to-end vascular anastomoses with a carbon dioxide laser

This study was designed to compare anastomoses performed with a carbon dioxide laser and conventional anastomoses performed with 7-0 polypropylene suture. In each of 80 rabbits, the divided left carotid artery was anastomosed by a continuous suture technique and the right carotid was anastomosed with a carbon dioxide laser. In each of 40 additional rabbits, both end-to-end and end-to-side laser anastomoses were performed on the same carotid artery. The laser technique involved the placement of three stay sutures (end-to-end technique) or four stay sutures (end-to-side technique) of 7-0 polypropylene and an everting laser seal at a power level of 65 mW. The 1-year overall patency rate was 98% (78/80) in laser anastomoses, 79% (63/80) in suture anastomoses, and 95% (38/40) in combined end-to-end and end-to-side laser anastomoses. Microscopic findings in laser anastomoses demonstrated degeneration of collagen and protein in the adventitia and media, but much less intimal injury than in suture anastomoses, with reendothelialization beginning earlier (within 7 days after anastomosis as compared with 2 to 4 weeks). The tissue tensile strength at 1 hour was less in laser anastomoses than in suture anastomoses, but the laser anastomoses still withstood an intraluminal pressure load of 380 mm Hg. Laser anastomosis improved the microscopic and histologic appearance of the intimal layer, allowing for rapid early reendothelialization and resulting in excellent patency rates.     

Healing of experimental colonic anastomoses. The effect of suture technic on collagen concentration in the colonic wall.

The present experimental study in rats has demonstrated a marked difference in the healing process of anastomoses in the left colon following two different suture technics: continuous and interrupted sutures. Rats having anastomoses constructed of continuous suture showed a high incidence of complications and a marked decrease of collagen concentration in the anastomosis and in the colonic wall proximal to the anastomosis during the first week of healing. In animals with anastomoses made of interrupted sutures there were fewer complications, the decrease in collagen concentration was confined to the anastomotic region, and the recovery of collagen concentration occurred earlier. The findings indicate that the interrupted suture technic is preferable for anastomosis in the left colon.     

Absorbable polydioxanone suture for venous anastomoses: experimental studies using venography and transluminal angioscopy

Because of their increased tendency to stenosis and spasm and thrombosis, results after venous anastomoses are often unsatisfactory. Nonabsorbable sutures and a continuous suture technique have been suggested to have a negative effect on the compliance of vascular anastomoses. Eighty venous anastomoses were performed with either an interrupted or continuous suture technique, using polypropylene or polydioxanone (PDS) sutures, according to a randomised experimental model. The anastomoses were divided in four groups: (1) Nonabsorbable suture material, continuous suture technique; (2) Nonabsorbable suture material, interrupted suture technique; (3) Absorbable suture material, continuous suture technique; and (4) Absorbable suture material, interrupted suture technique. The morphology of the anastomoses was controlled by venography directly after closure of the wound and at weekly intervals for 2 months and monthly intervals thereafter until 2 years had passed. In 10 cases venography was followed by transluminal angioscopy in the early postoperative period and after 1, 2, 4, 8 and 12 weeks. In the first 2 months moderate and high degree stenoses were found in all 4 groups by venography. After 8 weeks there was a significant decrease in the incidence of stenosis in all groups with the exception of the group, in which continuous nonabsorbable suture had been used. Using angioscopy a marked swelling of the intima at the site of the anastomoses could be detected in the early postoperative period in all experimental groups. After 2 months no significant narrowing could be identified in groups 2, 3 and 4.(ABSTRACT TRUNCATED AT 250 WORDS)