Clinical use of the 3M 2.5 mm mechanical microcoupling device in free tissue transfer

Exploring the supremacy of microvascular coupling devices for arterial anastomosis in terms of added expeditiousness, safety concerns: A systematic review

Background

Arterial anastomoses are still most commonly performed using orthodox hand sewing technique. Various rationale such as non-pliable, atherosclerotic, thick-walled or irradiated vessels limit the competency of coupler devices for arterial micro-anastomosis. Microvascular coupling devices (MCD) are well known for venous anastomoses but arterial MCD have relatively been less navigated in reported literatures. This review outlines the current applications, troubleshooting, safety and efficiency of arterial MCD in free flaps.

Methods

Comprehensive search of electronic databases (PUBMED/MEDLINE) in accordance with PRISMA guideline was performed. Data were extracted and collected in four groups of standardised variables.

Results

Out of a total of 263 identified articles, 38 studies were analysed and 16 amidst these were included in final data synthesis. Included studies contained a combined total of 2416 patients who went through 521 arterial and 2460 venous anastomoses using 3 M/Synovis coupling devices. Among all coupled arterial anastomoses, 407 were conducted in head and neck free tissue transfer and 114 were performed in breast reconstruction. The aggregate coupled arterial micro-anastomosis success rate reported was 90.01 % (469/521). Only 9.98 % (52 out of 521) manifested pooled incidence of troubleshooting, thrombosis or flap failure.

Conclusion

Microsurgeons are resisting the frequent use of arterial coupling devices owing to inherent arterial characteristics, but with suitable vessel selection, arterial coupling may be a powerful tool and can be executed in safe, expeditious and reliable fashion. This study embellishes collaborative suggestions and troubleshooting issues related to arterial coupling, however further assessment would be required with controlled trials.

Is there a difference in venous thrombosis rate in free flap anastomoses based on coupler diameter? A systematic review. Does Size Really Matter?

Background

The adage is to use the largest anastomotic coupler device (coupler) size possible, since smaller an anastomosis might be more susceptible to thrombosis. It is unclear if this wisdom is supported by data. This study tests the hypothesis that there is no difference in the reported literature in thrombosis rate between different coupler sizes.

Methods

We searched PubMed, Embase, and the Cochrane Library. After screening 235 studies, we included 11 retrospective case-series. According to the criteria of Newcastle–Ottowa Scale, quality score ranged from 2 to 4 (out of 5) and funnel plots indicated publication bias. We included a total of 5930 coupled anastomoses. We calculated thrombosis rate per coupler diameter with exact confidence intervals (CIs). We regard non-overlapping CIs as a significant difference.

Results

Nine studies reported no difference in thrombosis rate based on coupler size. Two studies report a potentially greater thrombosis rates in smaller sizes: (1) 2.0 mm 27% (95% CI 17%–40%, 17/62 cases) vs. 3.0 mm 6.3% (95% CI 2.8%–12%, 8/126 cases) and (2) 1.5 mm 6.9% (95% CI 2.8%–14%, 7/101 cases) vs. 3.0 mm group 1.2% (95% CI 0.64%–2.1%, 13/1079).

Conclusion

There is some evidence that suggests that smaller coupler sizes are associated with greater thrombosis rate, but the current available evidence has limitations. Performing a second anastomosis, in case, the first anastomosis is performed with a coupler size of 1.0, 1.5, or even 2.0 mm, can potentially reduce this rate, however, this remains to be determined.

Evaluation of a microvascular anastomotic coupler for end-to-side arterial and venous anastomosis for feline renal transplantation

OBJECTIVE

To describe the technique and determine the feasibility of an end-to-side (ETS) anastomosis of the renal vein to vena cava and renal artery to aorta using a microvascular anastomotic coupler (MAC) for feline renal transplantation.

STUDY DESIGN

In vivo experimental study.

ANIMALS

Six purpose-bred domestic shorthair cats.

METHODS

The left kidney was autotransplanted using a MAC for ETS vascular anastomosis. Outcomes included intraoperative hemorrhage from the anastomosis sites, duration of anastomoses, surgical complications, postoperative renal perfusion (including resistive index (RI)) measured by Doppler ultrasonography and computed tomography angiography, and histopathological examination of the left kidney and anastomosis sites (30 days).

RESULTS

Anastomosis was successful in all cats, and intraoperative hemorrhage was negligible. Intraoperative renal perfusion was considered excellent. Venous and arterial anastomoses were completed in 11 minutes 20 seconds (range, 6:38-13:27) and 21 minutes 50 seconds (range, 11:05-30:24), respectively. Vascular occlusion time was 32 minutes (17:43-42:03). One cat was euthanized 5 hours postoperatively because of bleeding from a muscular arterial branch of the dorsal aorta causing hemoabdomen. Renal perfusion and RI of the remaining five cats were within normal range (<0.8) and similar to the contralateral kidney at all time points. Endothelialization of the anastomosis was complete with mild-to-moderate fibrosis surrounding the MAC in all cats.

CONCLUSION

End-to-side anastomosis of the renal vein and artery to the vena cava and aorta, respectively, was consistently achieved in all six cats with the MAC.

CLINICAL SIGNIFICANCE

The use of the MAC may be considered as an alternative to hand suturing for ETS anastomoses for feline renal transplantation.

Microvascular coupler device versus hand-sewn venous anastomosis: A systematic review of the literature and data meta-analysis

BACKGROUND

Successful vascular anastomosis is essential for the survival of free tissue transfer. The aim of the study is to review the current literature and perform a meta-analysis to assess the potential advantages of a mechanical anastomosis coupler device (MACD) over the hand-sewn (HS) technique for venous anastomoses.

METHODS

A systematic Medline search was performed to gather all reports of articles related to MACD from 1984 until now. The following data were extracted: first author and publication date, study design, number of patients and anastomosis, coupler size, site and type of reconstruction, venous anastomotic time, flap failure. A meta-analysis was performed on articles that met the following inclusion criteria: studies comparing MACD and HS technique in venous anastomosis, reporting anastomotic time, and postoperative complications.

RESULTS

Thirty-three studies were included for the analysis. Twenty-four were retrospective case series and nine were retrospective comparative studies. A total of 12,304 patients were enrolled with a mean age of 49.23 years (range 31-72). A total of 13,669 flaps were accomplished. The thrombosis rate recorded with MACD was 1.47%. The meta-analysis revealed that MACD significantly decreased anastomotic time (standard difference in means = -0.395 ± 0.105; Z = -3.776; p < .001) and postoperative flap failure risk (odds ratio [OR] = 0.362, 95% confidence interval [CI] = 0.218-0.603, Z = -3.908, p < .001), but it did not decrease postoperative venous thrombosis risk (OR = 0.504, 95% CI = 0.255-1.129, Z = -1.666, p = .096).

CONCLUSIONS

MACDs are a safe and effective alternative to traditional anastomosis. The anastomotic coupler is easier, much faster, and requires less technical skills than a HS microvascular anastomosis.

Use of venous couplers in microsurgical lower extremity reconstruction: A systematic review and meta-analysis

BACKGROUND

Free tissue transfer for lower limb reconstruction has become a workhorse procedure for limb-salvage. Compared with other recipient sites, the lower extremity has a higher risk of microvascular complications, in particular with venous anastomosis. The study's objective is to evaluate the evidence, safety, and efficacy of venous coupler use in microsurgical anastomosis in lower limb reconstruction to provide objective appraisal of the surgical techniques.

METHODS

A systematic review (SR) and meta-analysis (MA) were performed analyzing articles from PubMed, Cochrane, Embase, and Web of Science from January 1990, to August 2018. Abstracts and titles were screened and assessed for eligibility by independent reviewers. Following full-text review, articles were included in the SR and MA. Case reports were excluded. Cochrane Collaboration and the Quality of Reporting of Meta-analyses (QUOROM) guidelines were followed.

RESULTS

Out of 15 included studies that met the inclusion criteria for the SR, 9 were included in MA. Patients treated with venous couplers did not experience more surgical complications (risk ratio (RR) 0.79; 95% confidence interval (CI) 0.48-1.33; p = .38), total failure (RR 0.61; 95% CI 0.22-1.70; p = .34), venous compromise (RR 0.72; 95% CI 0.23-2.27; p = .57), arterial compromise (RR 0.85; 95% CI 0.25-2.88; p = .80), partial failure (RR 0.77; 95% CI 0.33-1.77; p = .54), or reoperation (RR 11.79; 95% CI 0.49-286.55; p = .13) in comparison with hand-sewn anastomosis.

CONCLUSIONS

Outcomes of venous couplers in lower limb reconstruction are comparable to those of hand-sewn anastomosis. However, this study was limited by the quality of the available literature. Additional prospective studies should aim to directly compare both techniques and potential further benefits in clinical trials.

Utilization of microvascular couplers in salvage arterial anastomosis in head and neck free flap surgery: Case series and literature review

BACKGROUND

In microvascular reconstruction of ablative oncologic defects, coupler devices have traditionally been used for venous anastomosis, whereas the arterial anastomosis is hand-sewn. In the setting of repeated intraoperative arterial anastomotic thrombosis, a coupler device may be of use in reducing the risk of rethrombosis.

METHODS

Two patients were seen with advanced stage head and neck cancer and underwent oncologic resection. During microvascular reconstruction, a clot at the arterial anastomosis was encountered in both cases.

RESULTS

After starting therapeutic anticoagulation and attempting unsuccessful suture reanastomosis, coupler devices were used for arterial anastomosis, resulting in viable free-tissue transfer.

CONCLUSIONS

Although traditionally used for venous anastomosis, coupler devices may serve a purpose in the salvage setting when facing repeated intraoperative arterial thrombosis.

Meta-analysis of venous anastomosis techniques in free flap reconstruction

BACKGROUND

Coupler devices and hand-sewn anastomosis techniques are both routinely employed for venous anastomosis in microsurgical free flap transfer. However, uncertainty remains about whether those two techniques are different in terms of risk of venous thrombosis. The aim of this review was to evaluate the quality of the evidence and quantify the difference in venous thrombosis rates in both techniques.

METHOD

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses compliant systematic review and meta-analysis were performed according to a previously published protocol. MEDLINE and Embase databases were searched from inception to 1 October 2018. Clinical studies using coupler devices for venous anastomoses in free tissue transfer were included. The primary outcome was post-operative venous thrombosis risk. Surgical anastomosis time was a secondary outcome. The risk of bias was assessed with the ROBINS-I or NIH tool and recommendations were made using the GRADE criteria.

RESULTS

A total of 10,851 patients across 32 observational retrospective studies were included, with data available for 12,769 free flaps in breast, head and neck, limb and other reconstructions. Direct comparison meta-analysis of 7 studies showed a reduced post-operative thrombosis risk for venous coupler, although this was an imprecise estimate (RR 0.68 [95% CI 0.39-1.19]). The risk of bias was consistently high across all studies.

CONCLUSION

Venous couplers may reduce the risk of venous thrombosis, but further randomised trial data are needed to improve the accuracy of this estimate. Further research should also assess size-mismatch between donor and recipient vessel, and the influence of coupler size on outcomes (PROSPERO registration ID: CRD42018110111).

Venous Thrombosis in Handsewn versus Coupled Venous Anastomoses in 857 Consecutive Breast Free Flaps

BACKGROUND

The anastomotic coupling device has demonstrated safety and efficacy; however, the coupler has never been compared directly to handsewn venous anastomoses exclusively in breast reconstruction. We hypothesized that rates of venous thrombosis would be lower using the coupler versus handsewn anastomoses in free flap breast reconstruction.

METHODS

We performed a retrospective review utilizing clinic records, hospital records, and operative reports for 857 consecutive breast free flaps at a single institution from 1997 to 2012. Data were collected on reconstruction type, recipient vessels, timing, laterality, preoperative radiation, chemotherapy, venous thrombosis, and flap outcome. We compared rates of venous thrombosis between handsewn and coupled anastomoses for breast free flaps. Chi-square test was used to calculate statistical significance.

RESULTS

A total of 857 consecutive free flaps were performed for breast reconstruction in 647 patients over 16 years. The venous anastomosis was handsewn in 303 flaps, and the anastomotic coupler was used in 554 flaps. The rate of venous thrombosis requiring anastomotic revision in the handsewn group was 0.04% (12/303), compared with 0.01% in the coupled group (8/554; p = 0.02).

CONCLUSION

The anastomotic coupler was more effective in preventing venous thrombosis than handsewn anastomoses in our series. While our study demonstrates improved patency rates using the venous coupler in breast reconstruction, we were unable to definitively separate this finding from potential confounding variables due to the low rates of thrombosis in both the groups. Our data are consistent with current literature, which suggests that the coupler is a safe and effective alternative to hand sutured anastomoses.

The utility of the microvascular anastomotic coupler in free tissue transfer

BACKGROUND

The microvascular anastomosis remains a technically sensitive and critical determinant of success in free tissue transfer. The microvascular anastomotic coupling device is an elegant, friction-fit ring pin device that is becoming more widely used.

OBJECTIVE

To systematically review the literature to examine the utility of the microvascular coupler in free tissue transfer.

METHODS

A comprehensive database search was performed to identify eligible publications. Inclusion criteria were anastomotic coupler utilization and free-tissue transfer. Recorded information from eligible studies included patient age, follow-up, radiation history, number of free-flaps and failure rates, reconstruction subsites, number of coupled venous and arterial anastomoses, coupling time, conversion to sutured anastomosis, coupler size and thrombosis rates.

RESULTS

Twenty-five studies reporting on 3207 patients were included in the analysis. A total of 3576 free-flaps were performed within the following subsites: 1103 head and neck, 2094 breast, 300 limb or body, and 79 nonspecified. There were only 26 reported flap failures (0.7%). A total of 3497 venous and 342 arterial coupled anastomoses were performed. The primary outcome measure was thrombosis rates, and there were 61 venous (1.7%) and 12 arterial (3.6%) thromboses reported. Mean coupling time was 5 min, and 30 anastomoses (0.8%) were converted to suture.

CONCLUSION

Flap survival and revision-free application of the microvascular coupler occurred in more than 99% of cases. There is a substantial time savings with coupler use. Venous and arterial thrombosis rates are comparable with the best results achieved by sutured anastomosis and, when used by experienced surgeons, the coupler achieves superior results.

Technology-assisted and sutureless microvascular anastomoses: evidence for current techniques

BACKGROUND

Since the birth of reconstructive microvascular surgery, attempts have been made to shorten the operative time while maintaining patency and efficacy. Several devices have been developed to aid microsurgical anastomoses. This article investigates each of the currently available technologies and attempts to provide objective evidence supporting their use.

METHODS

Techniques of microvascular anastomosis were investigated by performing searches of the online databases Medline and Pubmed. Returned results were assessed according to the criteria for ranking medical evidence advocated by the Oxford Centre for Evidence Based Medicine. Emphasis was placed on publications with quantifiable endpoints such as unplanned return to theatre, flap salvage, and complication rates.

RESULTS

There is a relative paucity of high-level evidence supporting any form of assisted microvascular anastomosis. Specifically, there are no randomized prospective trials comparing outcomes using one method versus any other. However, comparative retrospective cohort studies do exist and have demonstrated convincing advantages of certain techniques. In particular, the Unilink™/3M™ coupler and the Autosuture™ Vessel Closure System® (VCS®) clip applicator have been shown to have level 2b evidence supporting their use, meaning that the body of evidence achieves a level of comparative cohort studies.

CONCLUSION

Of the available forms of assisted microvascular anastomoses, there is level 2b evidence suggesting a positive outcome with the use of the Unilink™/3M™ coupler and the Autosuture™ VCS® clip applicator. Other techniques such as cyanoacrylates, fibrin glues, the Medtronic™ U-Clip®, and laser bonding have low levels of evidence supporting their use. Further research is required to establish any role for these techniques.

Arterial coupling for microvascular free tissue transfer

OBJECTIVE

The purpose of this study was to demonstrate the efficacy of arterial coupling.

STUDY DESIGN

Retrospective data were collected in a consecutive series of 124 patients undergoing surgical resection of head and neck tumors followed by free tissue transfer (FTT).

METHODS AND MEASURES

The Unilink coupling device was used to perform arterial and venous anastomosis. Flap survival and thrombosis of the arterial anastomoses were determined.

RESULTS

A total of 124 consecutive patients underwent a total of 127 microvascular FTTs. Reconstruction included 90 radial forearm, 26 fibula, 9 rectus abdominis, and 2 iliac crest myocutaneous free flaps. There were four (3.2%) complications related to arterial insufficiency in our series, three of which were salvageable. There were three (2.4%) flap failures, resulting in an overall free flap survival rate of 97.6 percent.

CONCLUSION

The flap survival with the Unilink Microvascular Anastomotic System is similar to that of standard suture techniques. Use of a coupler device is the preferred method in performing microvascular FTT at our institution.

Venous Thrombosis in Coupled Versus Sutured Microvascular Anastomoses

BACKGROUND

The anastomotic coupling device (ACD) is currently used for microsurgical venous anastomoses as an alternative to sutures and can reduce anastomotic time.

METHODS

We reviewed the microsurgical procedures performed at the University of Texas M. D. Anderson Cancer Center over a 40-month period. Procedures were performed for elective reconstruction of the breast, head or neck, or extremities after tumor excision. Thrombosis and ultimate flap salvage rates were compared between cases using ACDs and those using sutures for the venous anastomoses.

RESULTS

Seven hundred twenty-three free flaps were included in the study. There were no intraoperative technical complications using the ACD. Overall, the venous thrombosis rates were not significantly different between the ACD (1.4%, 2/139 cases) and sutured (3.3%, 19/584 cases) groups. Salvage rates following venous thrombosis were not significantly different for venous anastomoses performed with an ACD (50%, 1 of 2 cases salvaged) compared with venous anastomoses performed with sutures (68.4%, 13 of 19 cases salvaged).

CONCLUSION

The ACD is a useful alternative to sutured venous anastomoses that can reduce anastomotic time while achieving similar patency rates.

ENDO-GIA Staplers for Side-to-Side Anastomosis of Veins

OBJECTIVE

To study the application of ENDO-GIA staplers for the side-to-side anastomosis of veins.

MATERIALS AND METHODS

An animal study was conducted. Five dogs received side-to-side anastomosis of allograft IVC by ENDO-GIA staplers (Group 1). In addition, five received the same operation with right renal vein reimplantation to allograft IVC (Group 2). Five dogs, receiving the same operation as in Group 1 using polypropylene sutures (control group, Group 3). An autopsy was performed if the dogs survived more than 8 weeks.

RESULTS

The IVC anastomosis remained patent in four subjects (80%) for Group 1, in five subjects (100%) for Group 2 and in four subjects (80%) for Group 3.

CONCLUSIONS

From the results of our experiment, ENDO-GIA staplers can be considered for use in the side-to-side anastomosis of large veins such as piggyback cavacaval side-to-side anastomosis in cadaveric orthotopic liver transplantation (OLT) or side-to-side splenorenal shunt in portal hypertension.

Routine Use of Microvascular Coupling Device for Arterial Anastomosis in Breast Reconstruction

BACKGROUND

Although microvascular coupling devices are used routinely and successfully for venous anastomosis, there are few published reports demonstrating their efficacy for performing arterial anastomosis. It has been the senior author's (C.Y.A.) preference to perform arterial anastomosis using the microvascular coupling device when feasible.

METHODS

All microsurgical breast reconstructions performed by the senior author at the New York University Medical Center between 1998 and 2004 were retrospectively reviewed. A total of 60 patients underwent microsurgical breast reconstruction, of which 20 were bilateral, for a total of 80 flaps.

RESULTS

Of the 80 flaps performed, there were 47 muscle-sparing TRAM and 22 deep inferior epigastric perforator (DIEP) flaps, and 11 were superior gluteal flaps. Arterial coupling was successfully performed in 60 of 69 flaps based on the deep inferior epigastric artery (87%) and 2 of 11 gluteal flaps (18%); arterial coupling was performed successfully 62 of 74 times (83.9%) when the thoracodorsal artery was the recipient vessel and never performed when the internal mammary artery was the recipient vessel. The overall flap success rate was 100%.

CONCLUSIONS

In our large series, we were able to perform a coupled arterial anastomosis in nearly 80% of the cases, without the loss of any flaps. With proper vessel selection and sufficient experience using the microvascular coupler, arterial coupling may be performed in an expeditious, safe, and reliable fashion with minimal morbidity. Though not commonly practiced, use of the coupling device for arterial anastomosis can provide significant time savings, especially in bilateral breast reconstructions.

First-year outcomes of beating heart coronary artery bypass grafting using proximal mechanical connectors

BACKGROUND

To determine the extended results of mechanical connectors we compared the 1-year outcomes of patients having beating heart coronary artery bypass surgery with at least one sutured or mechanically connected proximal vein graft anastomosis.

METHODS

From May 2001 to December 2001, 166 patients were identified as having undergone off-pump bypass grafting utilizing at least one St. Jude symmetry aortic connector (St Jude Medical Anastomotic Technology Group, St. Paul, MN). Follow-up for major adverse cardiac events (MACEs), which is defined as cardiac mortality, myocardial infarction, or revascularization of a previous target vessel, was obtained on 162 patients (97.6%). A control group of 159 patients was identified from a cohort of patients having beating heart surgery with one or more sutured proximal vein graft anastomosis in the preceding year. The MACE follow-ups were obtained in 136 patients (85.6%) by direct telephone contact.

RESULTS

Patients with connectors showed an accelerated number of MACEs beginning approximately 180 days from the time of surgery and stabilizing at approximately 300 days. Logistic regression analysis identified the presence of diabetes as a significant preoperative risk factor predisposing patients to earlier onset of MACEs (p = 0.03) with an odds ratio of 2.9 (95% confidence interval, 1.1 to 7.6). Insulin dependent diabetics showed no differences between connector and control patients in the frequency or timing of MACEs. Connector patients using oral hypoglycemic agents demonstrated a significant deviation (p = 0.01) from a similar control population in the prevalence and timing of MACEs.

CONCLUSIONS

Connector patients showed an increased incidence of early MACEs. These events were characterized by an increased requirement for early target vessel revascularization and were predominantly in noninsulin-dependent diabetics.

Non-suture methods of vascular anastomosis

BACKGROUND

The main aim of performing a vascular anastomosis is to achieve maximal patency rates. An important factor to achieve that goal is to minimize damage to the vessel walls. Sutures inevitably induce vascular wall damage, which influences the healing of the anastomosis. Over time, several alternatives to sutures have become available.

METHODS

A Medline literature search was performed to locate English, German and French language articles pertinent to non-suture methods of vascular anastomosis. Manual cross-referencing was also performed and many historical articles were included.

RESULTS AND CONCLUSION

The non-suture techniques can be categorized into five groups based on the materials used: rings, clips, adhesives, stents and laser welding. With all these techniques a faster and less traumatic anastomosis can be made compared with sutures. However, each device is associated with technique-related complications. As a consequence, suturing continues to be the standard approach. The disadvantages of the non-suture techniques include: rigidity and a non-compliant anastomosis with rings; toxicity, leakage and aneurysm formation with adhesives; early occlusion with stents; cost, reduced strength in larger-sized vessels and demand for surgical skills with laser welding. Further refinement is needed before widespread adoption of these techniques can occur. Clips, however, may be particularly promising but long-term evaluation is required.

Two generations of the St. Jude Medical ATG coronary connector systems for coronary artery anastomoses in coronary artery bypass grafting

BACKGROUND

In the past, coronary anastomoses have been performed using running and, occasionally, interrupted non-resorbable sutures. Recently, special interest has developed in mechanical anastomotic devices to facilitate minimal invasive techniques or limited access surgery. The experience with two series of patients undergoing coronary artery bypass grafting (CABG) using the St. Jude Medical ATG coronary connector systems (investigational stainless steel device, not yet commercially available) for vein-to-coronary artery anastomoses is reported here.

METHODS

Between November 2000 and April 2002, we evaluated two generations of distal coronary connector systems in 19 patients who were scheduled for multivessel CABG. One vein graft-to-coronary artery anastomosis per patient was performed with a stainless steel mechanical connector, in an ongoing investigational study. Although these two generations of the St. Jude Medical ATG coronary connectors have the same underlying construction, somewhat cumbersome loading of the first-generation system led to simplification of the second-generation system, which is currently evaluated.

RESULTS

With the first generation of distal connector, hemostasis was instantaneous in all cases, and all anastomoses were patent at the end of the procedure. However, retrograde flow to the native coronary artery was restricted in 1 patient. The connector was removed, and the anastomosis was performed with a running suture at the same site. Three-month angiography or magnetic resonance imaging angiography was available in 11 patients with 10 patent connector grafts. With the second-generation connectors one of five had to be removed because of leakage, and the anastomosis could be sutured at the same site. The other four connector anastomoses were patent and hemostatic at the end of the procedure.

CONCLUSIONS

The St. Jude Medical ATG coronary connector system is an effective device for sutureless vein graft to coronary artery anastomoses in CABG. The second-generation system presents a further development eliminating some drawbacks of the first generation such as cumbersome, time-consuming loading as well as suitability for smaller coronary arteries. These connectors allow construction of geometrically round anastomoses and theoretically may also be suitable for sequential anastomoses. After tremendous research and development efforts, an optimized mechanical connection system for small vessel anastomoses has been introduced into clinical investigation. This represents a major step in the era of sutureless vascular connections in cardiac surgery.

The St Jude Medical symmetry aortic connector system for proximal vein graft anastomoses in coronary artery bypass grafting

OBJECTIVES

A new device designed to create proximal vein graft anastomoses to the aorta in coronary artery bypass grafting was recently developed by the St Jude Medical Anastomotic Technology Group (Minneapolis, Minn). This new anastomosis system consists of a nickel-titanium (nitinol) connector, an aortic cutter, and a delivery device.

METHODS

The loading of the vein on the aortic connector and its delivery to the aorta are described. In 43 consecutive patients (mean age 68 +/- 10 years, age range 33-91 years), 65 proximal vein graft anastomoses were performed with the new system. Intraoperative flow rates were assessed for all grafts according to the transit time principle.

RESULTS

All connector anastomoses were performed without the use of any aortic clamp. Times to complete these mechanical anastomoses were less than 10 seconds in all cases. Hemostasis was instantaneous in all cases, with only 3 system failures. These connectors were easily removed so that the anastomoses could be performed with standard suturing technique through the same aortotomy without complications. All vein grafts were patent at the end of the procedure, and there were no intraoperative or postoperative complications related to the device.

CONCLUSIONS

The aortic connector system was easy to handle and allowed quick creation of reliable, reproducible, and uniform anastomoses. In addition, anastomoses could be done without any clamping of the aorta, which is especially attractive for off-pump procedures, because aortic manipulation and therefore the risks of embolism and aortic dissection would be further minimized. In on-pump cases this technique would facilitate the single-clamp technique, again minimizing aortic manipulation.

Clinical outcome of digital replantation using the fibrin glue-assisted microvascular anastomosis technique

A series of 36 digital replants is reported in which microvascular anastomoses were each performed with four to six stitches and topically applied fibrin glue. Thirty-two digits survived, comparable to survival with conventional microvascular anastomosis. The average operative time per replanted digit was 3.2 hours, considerably less than documented with standard replantation technique (4.5 hours per digit). These clinical findings indicate that fibrin glue-assisted microvascular anastomosis does not compromise replant outcome and can reduce the operative time by reducing the number of microsutures that need to be placed in each anastomosis.

Clinical experience with a microvascular anastomotic device in head and neck reconstruction

BACKGROUND

Despite numerous refinements in microsurgical technique and instrumentation, the microvascular anastomosis remains one of the most technically sensitive aspects of free-tissue transfer reconstructions.

MATERIALS AND METHODS

Concurrent with the development of microsurgical techniques, various anastomotic coupling systems have been introduced in an effort to facilitate the performance and reliability of microvascular anastomoses. The microvascular anastomotic coupling device (MACD) studied here is a high-density, polyethylene ring-stainless steel pin system that has been found to be highly effective in laboratory animal studies. Despite its availability for human clinical use over the last 5 years, reported clinical series remain rare. Our clinical experience with this MACD in 29 head and neck free-tissue transfers is reported herein.

RESULTS

Thirty-five of 37 (95%) attempted anastomoses were completed with 100% flap survival with a variety of donor flaps, recipient vessels, and clinical contexts. Two anastomoses were converted to conventional suture technique intraoperatively, and one late postoperative venous thrombosis occurred after fistulization and vessel exposure.

CONCLUSIONS

We conclude that the MACD studied here is best suited for the end-to-end anastomosis of soft, pliable, minimally discrepant vessels. Previous radiation therapy does not appear to be a contraindication to its use. Interpositional vein grafts may also be well suited to anastomosis with the device. When carefully and selectively employed by experienced microvascular surgeons, this MACD can be a safe, fast, and reliable adjunct in head and neck free-tissue transfer reconstructions, greatly facilitating the efficiency and ease of application of these techniques.