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.     

Comparison of laser vascular welding,interrupted sutures,and continuous sutures in growing vascular anastomoses

Background and Objectives: The argon laser-assisted vascular anastomosis may solve the problems of conventional sutured anastomosis, such as vascular stenosis and arrest of growth owing to a foreign-body reaction to suture material. Study Design/Materials and Methods: Twelve argon laser-assisted vascular anastomoses, seven conventional anastomoses with interrupted sutures, and five conventional anastomoses with continuous sutures were performed in 12 young mongrel dogs. Results: Five months later, the external diameter at the anastomosis had increased 70.5% in the laser group, 67.0% in the interrupted suture group, and 22.9% in the continuous suture group. Histological examination of the laser-assisted anastomoses showed almost complete healing, with no granulomatous response around the anastomotic site. In the interrupted suture group, marked scaring and foreign body reactions were observed on the vessel wall at the site of the anastomosis. The continuous suture group showed more remarkable disorientation of the vascular layer and intimal hyperplasia than the interrupted suture group. Conclusion: Vascular anastomosis using the argon laser offers advantages over the conventional procedure in growing vessels.     

Argon laser-welded arteriovenous anastomoses

This study compared the healing of laser-welded and sutured canine femoral arteriovenous anastomoses. Arteriovenous fistulas 2 cm in length were created bilaterally in the femoral vessels of 10 dogs and were studied at 1 (n = 2), 2 (n = 2), 4 (n = 3), and 8 (n = 3) weeks. In each animal, one anastomosis (control) was closed with running 6-0 polypropylene sutures, and the contralateral anastomosis (experimental) was sealed with an argon laser (0.5 watt, 4 minutes of exposure, 1830 J/cm2/1 cm length of anastomosis). At removal all experimental anastomoses were patent without hematomas, aneurysms, or luminal narrowing. Histologic examination at 4 weeks revealed that laser-welded anastomoses had less inflammatory response and almost normal collagen and elastin reorientation. At 8 weeks sutured anastomoses had significant intimal hyperplasia whereas laser repairs had normal luminal architecture. Tensile strength and collagen production, measured by the synthesis of hydroxyproline and the steady-state levels of type I and type III procollagen messenger ribonucleic acids, at the anastomoses and in adjacent vein and artery specimens were similar in sutured and laser-welded repairs at 2, 4, and 8 weeks. We conclude that argon laser welding of anastomoses is an acceptable alternative to suture techniques, with the advantage of improved healing without foreign body response and possible diminished intimal hyperplasia at the anastomotic line.     

Argon laser-assisted anastomoses in medium-size vessels: one-year follow-up

Laser-assisted anastomosis of medium-size vessels can be performed with satisfactory short-term patency. This study was undertaken to evaluate patency and structural integrity up to 1 year. An argon laser was used to make bilateral femoral arteriovenous anastomoses in 12 dogs compared to conventional suture method in another 8 dogs. These anastomoses were evaluated for patency and aneurysm formation at 1 hour; 1, 2, 4, and 8 weeks; and 12 months after surgery. All anastomotic sites were patent and without aneurysmal change or luminal narrowing at all harvesting intervals. Histologic examination revealed that within 1 month laser anastomotic sites were almost completely healed and without intimal hyperplasia. In suture anastomoses, foreign-body reaction remained evident up to 1 year. Use of the argon laser for medium size vessel anastomoses resulted in excellent patency without aneurysm formation or intimal hyperplasia even in the long term. These data suggest promising clinical applications.     

Initial evaluation of absorbable polydioxanone suture for peripheral vascular surgery

The long-term integrity of an autogenous vascular anastomosis is primarily dependent on the strength of tissue healing; therefore permanent mechanical support of an autogenous anastomosis with sutures is unnecessary. In this study we evaluated monofilament absorbable polydioxanone as an alternative to polypropylene for suturing autogenous vascular tissue during adult peripheral vascular operations. We used polydioxanone suture for 21 vascular procedures in 20 patients. We evaluated suture handling characteristics during operation and then followed patients with clinical assessments and serial duplex scans to monitor for pseudoaneurysms, anastomotic narrowing, and vessel patency. Indications for surgery included limb salvage (67%), dialysis access (23%), traumatic arteriovenous fistula and claudication (5% each). The operative procedures included infrainguinal bypass (57%), arteriovenous fistula formation (24%), thromboembolectomy (14%), and arteriovenous fistula repair (5%). Polydioxanone sutures were placed in 39 separate test sites (35 arterial, 4 venous). No deaths occurred during operation. Polydioxanone suture was found to have handling characteristics similar to polypropylene. During mean patient follow-up of 7.2 +/- 0.6 months, we found no cases of anastomotic narrowing or pseudoaneurysms. Actuarial test site patency at 1, 3, and 6 months was 97%, 97%, and 86%, respectively. Polydioxanone suture has handling properties that are acceptable for use in vascular applications, and it provides adequate mechanical support for sutured vessels to heal. A randomized trial comparing polydioxanone with polypropylene suture will be necessary to determine whether the lack of permanent foreign material in vascular anastomoses can improve long-term patency.     

Laser radiation in the treatment of prosthetic graft stenosis. A preliminary study of prosthesis damage by laser energy

Transluminal laser recanalization is potentially an important new treatment of anastomotic intimal hyperplasia. However, currently used grafts or sutures may be damaged by laser radiation at power and energy levels required for plaque removal. To investigate this problem, two commonly used grafts (Dacron and polytetrafluoroethylene [PTFE]) and two types of vascular suture (polypropylene and PTFE) were exposed to argon laser radiation in vitro. Dacron and PTFE grafts recovered from amputations were also studied to determine whether graft "healing" affected graft resistance to laser damage. Power and energy levels required to perforate atherosclerotic superficial femoral arteries were determined for comparison. PTFE grafts were significantly (1.5 to 7 times) more resistant to perforation by laser energy than atherosclerotic arteries under all conditions. In contrast, Dacron grafts perforated at power and energy levels one half to one third of that required for vaporization of atherosclerotic plaque. PTFE sutures remained intact at power and energy levels above the levels that perforated atherosclerotic arteries, whereas polypropylene sutures were destroyed by very low levels of power and energy (0.5 joules at 0.5 watts). Because of the variable levels of power and energy that damage different types of prosthetic grafts and sutures, laser angioplasty should only be investigated clinically as a therapy for anastomotic intimal hyperplasia when PTFE grafts and sutures are present.     

Anastomotic tissue response associated with expanded polytetrafluoroethylene access grafts constructed by using nonpenetrating clips.

PURPOSE: The gross, light microscopic, and scanning microscopic appearance of arterial and venous anastomoses in expanded polytetrafluoroethylene (ePTFE) access grafts constructed with nonpenetrating clips were compared with that of those constructed with polypropylene suture. We hypothesized that clip-constructed anastomoses would provide controlled approximation of native vessel intimal and medial components with the ePTFE grafts. We further hypothesized that anastomotic healing with clips would involve primarily an intimal cellular response, as compared with suture-constructed anastomoses in which cells within the media and adventitia walls participate. METHODS: Femoral artery to femoral vein arteriovenous (AV) grafts were constructed in five dogs using 4-mm internal diameter ePTFE graft material. Each animal received one AV graft with anastomoses constructed by using polypropylene sutures in one leg and one AV graft with anastomoses constructed with Vascular Closure System clips in the contralateral leg. Animals were given aspirin for the duration of the study, and grafts were explanted at 5 weeks. At the time of explantation, graft segments were grossly evaluated and then underwent light and scanning electron microscopic analysis. RESULTS: At the time of explantation, all access grafts were patent. Joining the ePTFE grafts to the native vessels with clips resulted in minimal vessel wall damage. The lumenal contours of the discontinuous approximation were smooth and without gross endothelial disruption. These observations are in contrast to the lumenal compromise and endothelial disturbance associated with the sutured anastomoses. Furthermore, hemostasis was achieved immediately in the clipped grafts, decreasing the incidence of perianastomic hematoma. Finally, cellular reconstitution occurred at the anastomotic cleft in both the sutured and the clipped junctions. The neointima exhibited an endothelial cell lining on the lumenal surface and the presence of alpha-smooth muscle cell actin positive cells within the subendothelial layer. CONCLUSION: Vascular Closure System clips are a viable alternative to suture for the approximation of ePTFE AV access grafts to native blood vessels. The use of the clips resulted in a more streamlined anastomosis, with decreased vessel wall damage, immediate hemostasis, and a trend toward shorter procedure times.     

Vascular anastomoses with absorbable suture material: An experimental study

A synthetic, monofilament, absorbable suture material, polytrimethylene carbonate, was tested to determine its suitability for use in arterial anastomoses. The material studied is a copolymer made of trimethylene carbonate and polyglycolic acid, with a retention time in the tissue of up to six months. In an experimental group of 12 mongrel dogs, using simple end-to-end anastomoses, aortic and femoral patch grafts of bovine heterograft material and iliofemoral bypass implants of 5 mm of expanded polytetrafluoroethylene prostheses were performed and arteriographically and histologically documented. Direct intraindividual comparisons were made with the absorbable (polytrimethylene carbonate) and nonabsorbable (polypropylene, expanded polytetrafluoroethylene suture) materials, a total of 108 anastomoses. No suture material-related complications such as ruptures or suture line aneurysms occurred. Polytrimethylene carbonate sutures led to less inflammation and scar tissue formation than polypropylene sutures. Complete absorption of the suture material by hydrolytic decomposition was followed by an almost complete regeneration in all layers of the vessel wall. Regeneration of the connective tissue structures of the media was noted. Initial associated reactions in the intima eventually disappeared. Both suture materials were equivalent histologically in the early months of the study, but after 10 month follow-up differences were observed, especially in the structure of the media, apart from the fact that polytrimethylene carbonate is absorbed completely after four to seven months.     

Nd: YAG laser–welded canine arteriovenous anastomoses

This preliminary report describes formation of femoral arterio-venous fistulas (n = 10) in six dogs using a 1.32-μm wavelength Nd:YAG laser welding technique. Stay sutures (6-0 polypropylene) were placed at 5–7 mm intervals along the anastomoses for vessel apposition. Delivery of laser energy through a 400-μm diameter fiber optic was controlled by a new computer-based software system. At 3 mm distance above the anastomosis, energy fluences of 110–260 J/mm²/cm length of anastomosis were used for laser welding. One or two additional hemostatic sutures were required in seven of the ten anastomoses. Flow was maintained for 1–2 hours prior to tissue harvesting. No thrombosis or delayed anastomotic failures were observed after initial welding and repair. Histologic examination revealed good apposition and adherence between wall layers and a fibrinous coagulum at the intimal junctions. Mild thermal injury of the wall was present at some anastomoses. This early investigation suggests that a 1.32 μm Nd:YAG laser welding technique can successfully create large vessel arteriovenous fistulas in the canine. © 1994 Wiley-Liss, Inc.     

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.     

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.     

Technical frontiers for the vascular surgeon: laser anastomotic welding and angioscopy-assisted intraluminal instrumentation

Innovations in therapy for peripheral vascular disease include laser vessel welding and angioscopy-assisted intraluminal laser instrumentation. Vascular tissue fusion by laser occurs at energy levels lower than those required to coagulate or vaporize. CO2, argon, and Nd:YAG (1.06 micron) lasers have all been reported to fuse anastomoses in microvessels, but adequate welding of larger veins and arteries (3 to 8 mm in diameter) has only been accomplished with the argon laser. Laser welds heal comparably to sutured wounds but do not have the chronic foreign body reaction and disorientation of elastin and collagen associated with sutures. Preliminary evidence suggests that argon laser-welded anastomoses have less intimal hyperplasia than sutured anastomoses. Laser welding may also be a useful adjunct for sealing intimal flaps during endarterectomy. Additional work is needed to determine the mechanism, optimal parameters, and wavelengths required for vascular tissue fusion by laser. Direct application of laser light intraluminally has thus far been associated with a high incidence of vessel perforation. Angioscopy-assisted delivery of a metal hot-tip probe shows promise for angioplasty of occluded medium-sized arteries and for valvulotomy in in situ vein bypasses.     

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.     

Prolene sutures are not a significant factor in anastomotic false aneurysms

Anastomotic false aneurysms have been a significant complication in vascular surgery, and the sutures used have been a major cause. Monofilament sutures have been indicated as contributing to the formation of false aneurysm. However, most of the monofilament sutures operative in the formation of false aneurysms have been made of polyethylene. Polypropylene, although significantly different from polyethylene, has been associated and possibly confused with it. Very few anastomotic aneurysms have resulted from breakage of polypropylene sutures. In this series of 2,400 vascular anastomoses in which polypropylene sutures were used, there were 10 false aneurysms; however, only one resulted from suture failure. In that patient, two Dacron grafts were anastomosed with 5-0 polypropylene suture. Polypropylene is a satisfactory and safe suture material for vascular anastomoses. It does not fragment or break easily when properly handled, and therefore is not a principal cause of false aneurysms.     

The role of suture material on healing of vascular anastomosis

The effect of suture material on healing of vascular anastomosis was examined. Four types of vascular grafts, i.e., autogenous vein, preserved human umbilical cord vein, expanded polytetrafluoroethylene and double velour knitted Dacron, were implanted into the abdominal aorta of 78 adult mongrel dogs using two kinds of absorbable sutures (multifilament polyglycolic acid: PGA and monofilament polydioxanone: PDS) and a nonabsorbable suture (polypropylene: PP). The macroscopic findings and the histologic examinations showed that hyalinoid degeneration and calcification resulting from tissue ischemia due to tight and long lasting suture loops interfered with tissue healing at the PP-anastomotic site. On the other hand, fairly good healing of the anastomoses was observed with absorbable sutures because of the reduction of ischemia. The absorbable suture-anastomoses could tolerate systemic blood pressure within one month after implantation, and there was no anastomotic disruption at 1000 mmHg pressure in the bursting test 12 months after grafting. From Dec., 1984, 55 anastomoses in 34 bypass-operations employing autogenous vein grafts were performed using PGA and PDS in 28 cases clinically. There were no anastomotic complications. In conclusion, the synthetic absorbable suture material, especially in the form of monofilament, seems to be most suitable for suturing or anastomosing autogenous small vessels at present.     

Arcuate-legged Nonpenetrating Vascular Closure Staples (VCS): Early Experience

Vascular closure staples (VCS) provide a novel technique for fashioning vascular anastomoses, allowing a single operator to perform suture-less anastomoses. They may be used primarily or in an adjuvant role. When VCS are compared to a running suture, advantages include the avoidance of intimal damage, platelet aggregation and intimal hyperplasia at the anastomotic suture line, and a shorter time taken to complete the anastomosis. We report our early experience using VCS in an array of vascular anastomoses and conclude that VCS are a useful addition to the vascular surgeon's armamentarium. They help to decrease the time taken to construct an anastomosis, and are particularly useful in an adjuvant setting, complementing conventionally placed sutures.     

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.     

Comparison of indium 111 oxine-labeled platelet aggregation between sutured and argon laser-assisted vascular anastomoses

The thrombogenicity of argon laser-assisted vascular anastomoses (LAVAs) was compared with that of sutured vascular anastomoses (SVAs) by measurement of platelet aggregation at the site of repair in a canine model. Sequential 1 cm longitudinal carotid and femoral arteriotomies (n = 80) or jugular and femoral phlebotomies (n = 80) were performed, with each vessel having two tandem, randomly positioned arteriotomies or phlebotomies separated by a 4 cm length of intact vessel. One incision was repaired by SVA with continuous 6-0 polypropylene sutures and the other by argon LAVA. For the laser fusions, argon laser energy was applied to the adventitial surface of the vessel with a 300 micron fiberoptic probe with 0.5 W power, 1100 joules per square centimeter energy fluence, and 150 second exposure per 1 cm length. The arterial and venous segments of SVAs and LAVAs and an equivalent length of normal vessel were harvested at 48 hours (n = 16, 16, 16), 2 weeks (n = 12, 12, 12), and 4 weeks (n = 12, 12, 12). Autologous indium 111 oxine-labeled platelets were injected intravenously 48 hours before removal of the vascular repairs and the radioactivity of the specimens was determined on removal with a NaI (T1) well-type scintillation counter. Anastomotic platelet adherence index (APAI) was calculated as the ratio of emissions of SVA or LAVA to normal reference vessel.(ABSTRACT TRUNCATED AT 250 WORDS)     

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.     

手术缝线携载反义基因预防血管吻合口内膜增生的实验研究

目的：探讨预防血管吻合口内膜增生的新方法。了解手术缝线携载反义基因对吻合口内膜增生的影响。方法：用分别浸泡过反义，正义及错配c-myc基因溶液的保护薇乔缝线行兔颈外静脉间置于同侧颈总动脉的血管吻合。实验动物24只随机分为对照组，反义组，正义组和错配组，每组6只，4周后血管造影观察吻合口通畅情况，同时取材制片显微镜下观察其内膜增生情况，计算机图像分析测量其内膜，中膜厚度及两者比值；内膜，中膜面积及两者比值。结果：所有吻合口通畅，未见闭塞，扩张或动脉瘤，反义组的内膜厚度，内膜／中膜厚度比值及内膜面积，内膜／中膜面积比值较其他组均低（P＜0．05），其他3组间比较差异均无显著意义（P＞0．05）；各组间的中膜厚度及中膜面积间差异无显著意义（P＞0．05），结论：用浸泡过反义 c-myc溶液的保护薇乔缝线进行血管吻合，能有效地抑制血管吻合口内膜增生。