Nitinol U-clips Research Articles

Eleven-year outcomes of U-clips in totally robotic coronary artery bypass grafting versus standard hand-sewn running suture in robotic-assisted coronary artery bypass grafting.

The aim of this study was to evaluate the clinical outcomes of patients undergoing off-pump robotic coronary artery bypass grafting (CABG) with either interrupted nitinol U-Clips in totally endoscopic coronary artery bypass (TECAB) or standard running suture anastomosis in robotically assisted direct coronary artery bypass (RADCAB) over a decade. From January 2007 to December 2017, 280 patients underwent robotic off-pump CABG using the da Vinci S/Si Surgical System in our centre. TECAB with interrupted nitinol U-Clips anastomosis was performed in the left internal mammary artery (LIMA) to LAD grafting in 126 patients and RADCAB (n = 154) of the LIMA to LAD was completed with standard running suture. After discharge, patients were contacted through telephone interview and were invited to attend the outpatient clinic every 6 months or 1 year. The graft patency was assessed by coronary angiography or computed tomography angiography. All cases were completed without conversion to median sternotomy or cardiopulmonary bypass. A total of 275 single internal mammary artery (IMA) grafts (271 LIMAs, 4 right internal mammary arteries) and 5 bilateral IMA grafts were used as single graft or composite grafts. All the patients were discharged without in-hospital mortality or adverse outcomes. The average follow-up was 89.7 ± 30.4 months (range, 14-143 months). The cumulative survival rates (P = 0.53), the cumulative IMA patency rates (P = 0.83), and the rates of freedom from major adverse cerebrovascular and cardiovascular events (P = 0.41) between TECAB and RADCAB all showed no significant difference in the follow-up. Robotic off-pump CABG using IMA grafts is safe and can provide reliable long-term outcomes. Compared with the standard hand-sewn running suture technique in RADCAB, interrupted suture with the nitinol U-Clips in TECAB showed similar long-term clinical results and graft patency in LIMA to LAD bypass grafting.

Robotic mitral valve repair: 7-year surgical experience and mid-term follow-up results.

The feasibility and safety of robotic mitral valve repair has been proven in several studies but the mid-term to long-term outcomes are unclear. We aim to summarize our surgical experience with robotic mitral valve repair and demonstrate the follow-up results out to 7 years. From 2007 to 2014, 110 consecutive patients underwent robotic mitral valve repair with da Vinci Surgical System (Intuitive Surgical, USA) in our center. The operative data were collected, and patients were echocardiographically followed regularly up to 7 years. The patients' average age was 45±13 (14 to 70) years with male to female ratio of 2.3:1. Mitral regurgitation (95.5%) or stenosis (4.5%) was diagnosed. The triangular or quadrangular resection was the most performed type of repair (63.3%). Nitinol U-clips (58.1%), running suture (31.1%), and Cor-Knot™ suture device (LSI Solutions, Victor, NY) (10.8%) were used to secure the annuloplasty ring. All cases were performed by the same surgeon. One case of conversion to sternotomy was noted. The mean CPB time was 121±34.3 (range, 70 to 152) minutes, and the mean cross-clamp time was 82.6±25.3 (range, 47 to 122) minutes. After surgery, one death (0.91%) and two cases of transient neurocognitive defect (1.82%) occurred. Three cases of early failure of repair that required reoperation (2.73%) were noticed. All patients were successfully followed for a median of 4.1 (range, 1 month to 7 years) years and 94.5% had freedom of re-operation. Robotic mitral valve repair is a safe and effective procedure with excellent mid-term outcomes.

Robotic mitral valve repair: perioperative and seven-year follow-up results

To summarize surgical experience during the conduction of robotic mitral valve repair and evaluate the long-term follow-up results. From January 2007 to September 2014, 110 consecutive patients underwent robotic mitral valve repair under da Vinci Surgical System (Intuitive Surgical, USA) in Chinese PLA General Hospital were enrolled. The age of the patients was 14 to 65(45±12) years old. The male to female ratio was 2.3∶1. Among them, 95.5%(105/110) of the cases was diagnosed as mitral regurgitation and 4.5%(5/110) of them was diagnosed as mitral stenosis, and most of them (63.3%) needed triangular or quadrangular resection. Nitinol U-clips (58.1%), running suture (31.2%) and Cor-Knot™ suture device (10.8%) were used to secure the annuloplasty ring. The operative data were collected and patients were regularly followed up echocardiographically as long as 7 years. All the surgeries were finished by the same surgeon. One case required conversion to sternotomy. The mean cardiopulmonary bypass (CPB) and cross-clamp time was 70 to 152 (121.0±34.3) and 47 to 122 (82.6±25.3) minutes respectively. After surgery, one death (0.91%) and two cases of stroke (1.82%) occurred. Three cases of early prosthetic failure (2.73%) were noticed. All patients were successfully followed up for a median of 50 (range, 1 month to 7 years) months and 94.5%(104/110) of them had no re-operation. Robotic mitral valve repair is a safe and effective surgical method with excellent long-term outcomes.

A Nitinol “U-Clip” versus Sutured Arteriovenous Anastomosis: Local Tissue Response and Intimal Hyperplasia Development in a Sheep Model

This study sought to compare the local tissue response and subsequent volume of intimal hyperplasia (IH) that develops throughout the maturation of an arteriovenous fistula created using continuous/interrupted polypropylene with that of a novel, metal-alloy, penetrating anastomotic clip device. Forty-six fistulae were created in 23 sheep under a paired design using the nitinol U-Clip (n = 23) in one hind limb and continuous (n = 20) or interrupted (n = 3) polypropylene suture for the other. Animals were killed at 4 (n = 3), 14 (n = 3), 28 (n = 10), 42 (n = 3), and 180 (n = 4) days. Histological sections were evaluated for quantitative histology and immunohistochemistry. Compared with continuous polypropylene, U-Clip specimens demonstrated less intima–media area per unit length (IMA/L), proliferating cells, and tissue necrosis at all time points (MANOVA, F = 9.8–24.1, all p≤.005; observed power >82%). Specifically, values of IMA/L were reduced by 5% (p = .97), 37% (p = .02), 33% (p < .01), 9% (p = .42), and 14% (p = .22) at the time points of 4, 14, 28, 42, and 180 days respectively. Proliferating cells were reduced by 75% (p < .01), 72% (p = .03), 76% (p = .03), 27% (p = .31), and 60% (p = .01) and tissue necrosis by 67% (p < .01), 58% (p = .02), 40% (p = .33), 21% (p = .43), 77% (p = .11). In a 28-day comparison between U-Clip and interrupted polypropylene the U-Clip group demonstrated a 4% (p = .65) reduction in IMA/L, 74% (p < .01) in proliferating cells and 49% (p < .05) in tissue necrosis. These results provide evidence of reduced local tissue necrosis, proliferating cells, and IH, favouring arteriovenous fistulae created using the U-Clip anastomotic device over conventional polypropylene suture techniques most evident over the first 4 weeks.

A Nitinol “U-Clip” versus Sutured Arteriovenous Anastomosis: Local Tissue Response and Intimal Hyperplasia Development in a Sheep Model

This study sought to compare the local tissue response and subsequent volume of intimal hyperplasia (IH) that develops throughout the maturation of an arteriovenous fistula created using continuous/interrupted polypropylene with that of a novel, metal-alloy, penetrating anastomotic clip device. Forty-six fistulae were created in 23 sheep under a paired design using the nitinol U-Clip (n=23) in one hind limb and continuous (n=20) or interrupted (n=3) polypropylene suture for the other. Animals were killed at 4 (n=3), 14 (n=3), 28 (n=10), 42 (n=3), and 180 (n=4) days. Histological sections were evaluated for quantitative histology and immunohistochemistry. Compared with continuous polypropylene, U-Clip specimens demonstrated less intima-media area per unit length (IMA/L), proliferating cells, and tissue necrosis at all time points (MANOVA, F=9.8-24.1, all p≤.005; observed power >82%). Specifically, values of IMA/L were reduced by 5% (p=.97), 37% (p=.02), 33% (p<.01), 9% (p=.42), and 14% (p=.22) at the time points of 4, 14, 28, 42, and 180 days respectively. Proliferating cells were reduced by 75% (p<.01), 72% (p=.03), 76% (p=.03), 27% (p=.31), and 60% (p=.01) and tissue necrosis by 67% (p<.01), 58% (p=.02), 40% (p=.33), 21% (p=.43), 77% (p=.11). In a 28-day comparison between U-Clip and interrupted polypropylene the U-Clip group demonstrated a 4% (p=.65) reduction in IMA/L, 74% (p<.01) in proliferating cells and 49% (p<.05) in tissue necrosis. These results provide evidence of reduced local tissue necrosis, proliferating cells, and IH, favouring arteriovenous fistulae created using the U-Clip anastomotic device over conventional polypropylene suture techniques most evident over the first 4 weeks.

A Prospective Evaluation of U-clips for Arterial Microvascular Anastomoses

The nitinol U-clip (Medtronic, Inc.; Minneapolis, MN, USA) is similar to conventional suturing but eliminates knot tying, thereby decreasing ischemia time. This study is the first clinical trial of this new technology for arterial microsurgical anastomoses in free tissue transfer. We performed a prospective clinical trial of nitinol U-clips for 25 consecutive arterial microsurgical anastomoses. Standard microsurgical techniques and instruments were used, and the primary outcome was free flap survival. The secondary outcomes were ischemia time, operating room (OR) time, number of clips used, and recipient/donor-site complications. Significant recipient/donor-site complications were defined as those requiring re-operation. Descriptive statistics were used and minimum follow-up was 3 months. All anastomoses were successful (25/25). The most common etiology of the defect was cancer resection (92%), and 44% of the recipient vessels had been irradiated prior to surgery. Mean ischemia time was 29 minutes (range 12 to 54 minutes), and mean OR time was 7.4 hours. On average, seven U-clips were used per arterial anastomosis (range 5 to 12). At 3-month follow-up, there was a 100% flap survival rate with no significant recipient-site or donor-site complications. This study suggests that the nitinol U-clip provides rapid, reproducible microvascular arterial anastomoses.

U-clip for airway reconstruction: an experimental study of the feasibility of a robot-assisted endoscopic procedure

The U-clip anastomotic device was developed to facilitate interrupted anastomoses without the need to tie sutures. Recently, this technology has been expanded into various fields of surgery. However, in the field of airway reconstruction, there have been no previous reports of this technology being used. The present study examined the technical feasibility of performing safe and efficient robot-assisted endoscopic airway reconstruction using nitinol U-clips in rabbits. A total of six tracheal anastomoses with S60 U-clips were performed using the da Vinci Surgical System. Anastomosis time and complications were recorded. The effectiveness of anastomoses was evaluated by postoperative observation of rabbits for 8 weeks and measurement of anastomotic strictures and pathological findings. All procedures were completed safely. Mean procedure time was 14 ± 1.8 min (mean ± SD). There were no perioperative complications; however, all animals died between postoperative days 14-27, and anastomotic stricture was the likely cause of death. All anastomoses had severe strictures; the mean stricture rate was measured as being 51.1 ± 33.3 (%). Although the technical feasibility of robot-assisted endoscopic airway reconstruction using U-clips has been demonstrated in rabbits, the safety of this technique has not been evaluated. Our data suggest that U-clips are not a feasible approach for airway reconstruction surgery because of the occurrence of severe postoperative anastomotic stricture.

Interrupted nitinol U-Clips versus standard running suture for the central arterial T-graft anastomosis: a prospective randomized study

Studies carried out to date suggest that the interrupted suture technique using U-Clips for anastomoses in coronary surgery may be superior to the standard running polypropylene suture. The purpose of this study was to compare safety and effectiveness of a central T-graft anastomosis constructed with the left internal thoracic artery (LITA) in situ (to the left anterior descending (LAD)) in which the free right internal thoracic artery (to the circumflex branch of the right coronary artery (RCX)) was implanted (RITA-to-LITA) using either self-closing nitinol U-Clips or simple continuous suture. We hypothesized that internal thoracic arteries could adapt their diameter to the blood flow. Thirty patients underwent total arterial revascularization using a T-graft constructed with free LITA in situ to LAD in which the free RITA to the circumflex artery was implanted (central T-graft anastomosis). In all cases, free RITA was used as a sequential graft with two peripheral anastomoses. Patients were randomly assigned to two groups: in group A (n=15), central T-graft anastomosis was performed using a standard 8/0 polypropylene running suture. In group B (n=15), central T-graft anastomosis was performed using U-Clips. Intra-operative transit time flow measurements were recorded. Patency control was performed in 30 patients 2 weeks and 6 months postoperatively, using 64-slice computed tomography (CT) angiography. The diameter of the LITA was measured proximal and distal and the diameter of the RITA distal to the central T-graft anastomosis. Perioperative results were similar in the two groups (P=ns). Intra-operative transit time flow measurement showed patent grafts in all patients. There were no hospital deaths. Two weeks postoperatively, all grafts were patent. At 6-month follow-up, one RITA and one LITA (both in group B) were closed distal to the central T-graft anastomosis. There was no death and no re-intervention during follow-up. Statistical analysis showed no significant changes in graft diameters after 2 weeks and 6 months in both groups. The U-Clip anastomosis technique is in our experience safe but not superior to the standard running suture using polypropylene material. Remodeling of the ITA grafts close to the central T-graft anastomosis was neither observed for the standard running suture nor for the U-Clip anastomoses.

Circumferential Watertight Dural Repair Using Nitinol U-Clips in Expanded Endonasal and Sublabial Approaches to the Cranial Base

In recent years, significant advances have been made in the field of expanded endonasal approaches that permit treatment of different cranial base intradural lesions. To report our technique of cranial base dural repair by the application of nitinol U-Clips in endoscope-assisted extended endonasal or sublabial approaches. Closure techniques and postoperative cerebrospinal (CSF) leaks are reported. We reviewed 11 patients with different kinds of cranial base tumors or vascular diseases (2 tuberculum sellae meningiomas, 1 planum sphenoidale meningioma, 4 craniopharyngiomas, 1 recurrent clival chordoma, 1 esthesioneuroblastoma, 1 ethmoidal melanoma metastasis, 1 basilar trunk aneurysm) who underwent an endoscope-assisted extended endonasal or sublabial approach. Dural repair was performed using nitinol U-Clips to circumferentially suture AlloDerm or fascia lata directly to the existing dural borders. Lumbar drainage was not used in 9 patients and was used in 2 patients for 5 days. Patients were evaluated for the appearance of CSF leaks. Postoperative CSF leak was observed in 1 patient (9%). This required a second transnasal repair. Circumferential dural closure with U-Clips is a useful adjunct to prevent CSF leaks after expanded endonasal or sublabial approaches to the cranial base for treatment of intracranial pathology.

Endoscopic Skull Base Suturing with a Self-Closing U-Clip: A Report of Two Cases and Review of the Literature

Objectives: Self-closing nitinol U-clips (Medtronic, Inc., Minneapolis, MN) have primarily been used by vascular surgeons to facilitate vessel anastomosis. The advantage of this device is that it obviates the need for suturing when manipulation of the tissue or needle is prohibitive. The current report describes a novel use of the U-clip as an aid in endoscopic reconstruction of the skull base. Methods/Participants: Two patients underwent U-clip assisted skull base repair. The first patient underwent transnasal endoscopic repair of an ethmoidal meningoencephalocele requiring primary dural closure and the second underwent odontoidectomy for basilar invagination via an endoscopic transnasal approach requiring primary closure of the soft tissues. Study Design – Case Series Results: The defects were successfully closed using the U-Clip anastomotic device. No cerebrospinal fluid leaks were experienced postoperatively. Intraoperative evaluation combined with postoperative imaging confirmed a satisfactory reconstruction. Conclusions: The U-clip device may be used as an adjunct in select cases to facilitate endoscopic skull base reconstruction. The use of this tool may prevent tissue migration and enhance dural closure. It may be particularly useful in cases where narrow operative corridors make conventional suturing technically difficult.

Self-closing Nitinol U-Clips for intracranial arterial microanastomosis: a preliminary experience on seven cases

To report experience on the use of self-closing nitinol U-Clips for different types of intracranial arterial microanastomosis. We treated 7 patients (3 females and 4 males, age ranging from 25 to 68 yo) admitted from November 2005 to January 2008 to the Neurological Institute C. Besta of Milan. One patient had cerebral hypoperfusion and the others a complex intracranial aneurysm. In each patient a bypass procedure was completed by using self-closing Nitinol U-Clips for intracranial arterial microanastomoses. The total time of temporary occlusion was 15.71 +/- 4.386 min. Bypass patency was confirmed intraoperatively by near-infrared indocyanine green videoangiography and microdoppler in each patient. No spasm of the graft was encountered and immediate post-operative bypass patency was confirmed in 6/7 patients. The graft thrombosed in 1 patient with antiphospholipid syndrome. 1 patient died from a massive Subarachnoid Hemorrhage due to rupture of an aneurysm while waiting for an endovascular procedure. In the 5 patients at the last follow-up, long-term patency of the bypass was confirmed and no neurological deficits occurred related to the procedure. This is the first report of the use of U-Clips for intracranial microanastomosis. Our data indicated that it is a safe technique, reduces the time taken to perform an anastomosis and the risk of an ischemic complication. Further studies of the longer-term patency of bypass as performed with U-Clips are required.

Use of self-closing U-clips for dural repair in mini-invasive surgery for herniated disc

The feasibility of a new technique of dural repair (self-closing U-clips) in mini-invasive surgery for herniated disk is demonstrated in this case report. A 44-year-old male patient underwent lumbar microdiscectomy at out Institute, with subsequent dural leak as surgical complication; the dural leak re-appeared even after a second intervention in which we used muscle and dural graft and fibrin glue to repair the leak. We then decided to employ self-closing nitinol- U-clip to achieve primary dural closure. After the intervention the patient no more presented signs or symptoms due to the unintended durotomy, and the postoperative course was uneventful. Self-closing nitinol U-clips (Medtronic, Inc., Minneapolis) can be used for closing a dural tear through a mini-invasive approach that could make a conventional microsuturing technique very difficult.

Repair of Indirect Inguinal Hernias by “Laparoscopic Joining of the Edges”

To evaluate a new laparoscopic technique for the treatment of indirect inguinal hernias. Using the rabbit model of indirect inguinal hernia, nitinol U-clips (Medtronic Inc, Minneapolis, MN) were applied to the edges of the internal inguinal ring to close the defect and induce a scar. The procedure required only a "needle-scope" and a 3-mm needle holder. Ten male New Zealand rabbits were divided in 2 groups: A=experimental (n=8 animals) and B=control (n=2 animals). Group A underwent laparoscopic placement of clips on day 1, with subsequent laparoscopic assessment on days 15, 30, and 60, and euthanized for histologic assessment on days 90 (n=4) and 120 (n=4). Group B underwent laparoscopy on day 0 (to confirm the presence of the hernias) and were euthanized on day 120. All treated inguinal hernias developed a thick layer of fibrous tissue around the clips and were completely closed (8 out of 8). At day 15 after surgery, all clipped areas showed some fibrosis, and at day 30, the clips were totally covered by scar tissue. The fibrosis involved not only the clips, but also a surrounding area of 2 to 3 cm. Mean operative time was 39 minutes (from skin incision to skin closure), and the mean time for clip placement was 2 minutes. The use of nitinol U-clips proved to be a simple, safe, and effective technique for the laparoscopic treatment of inguinal hernias in this animal model, which has a remarkable correlation with the anatomy of human pediatric indirect inguinal hernias.

Open vs laparoscopic repair of congenital duodenal obstructions: a concurrent series

Objective The advantages of using laparoscopy for repair of congenital duodenal obstructions (CDO) are unclear because of scant data about complications and outcomes. Nitinol U-clips (Medtronic Surgical, Minneapolis, Minn) were developed to assist in the creation of vascular anastomoses in small vessels. Because of their ability to approximate tissue tightly with little tissue damage, we have begun to use these U-clips for laparoscopic repair of CDO. In this report, we investigate the impact of laparoscopic U-clip repair of CDO compared to the traditional open repair. Methods With institutional review board approval, a retrospective analysis of all patients undergoing repair of CDO from January 2003 to July 2007 was performed. During this study period, patients who underwent open repair of CDO (group 1) were compared with patients that underwent laparoscopic repair using the U-clip technique (group 2). Results Twenty-nine patients underwent repair of CDO. Fourteen patients (11 atresia, 3 stenosis) were in group 1 and 15 patients (11 atresia, 4 stenosis) in group 2. A female sex bias existed in group 1 (female-male [9:5]) compared to group 2 (female-male [7:8]). There was no difference in birth weight, age at operation, chromosomal anomalies, or congenital heart disease between the groups. There were no duodenal anastomotic leaks in either group. Operative times were similar between groups (96 vs 126 minutes; P = .06). The length of postoperative hospitalization (20.1 vs 12.9 days; P = .01), time to initial feeding (11.3 vs 5.4 days; P = .002), and time to full oral intake (16.9 vs 9 days; P = .007) were all statistically shorter in group 2. Conclusions The laparoscopic approach to CDO repair using U-clips is safe and efficacious. In addition, patients undergoing laparoscopic repair of CDO had a shorter length of hospitalization and more rapid advancement to full feeding compared to babies undergoing the open approach. We feel that in the hands of experienced laparoscopic surgeons, the preferred technique for correction of CDO will become the laparoscopic U-clip repair.

Use of a Novel Penetrating, Sutureless Anastomotic Device in Arterial Microvascular Anastomoses

The advent of microsurgery and microvascular anastomosis has helped to alter the treatment of many traumatic defects as well as revolutionize the reconstructive options after extirpative surgery. These procedures, however, continue to be technically demanding and intensive. In addition, increased ischemia and operative times are known to raise complications in microsurgery, particularly in older patients. The nitinol U-clip (Medtronic, Inc., Minneapolis, MN) is a new penetrating clip applied in an interrupted fashion that eliminates knot tying and decreases operative time. This technology holds the potential for rapid, reproducible sutureless microvascular anastomoses. In addition, the surgical technique is very similar to conventional suture microanastomosis, lending itself to comparatively decreased learning curves and suitability for training programs. We present three consecutive cases of successful microsurgical anastomoses using this technology.

Significant reduction in annuloplasty operative time with the use of nitinol clips in robotically assisted mitral valve repair

A substantial barrier to widespread adoption of robotically assisted mitral valve repair surgery is increased operative time compared with that of median sternotomy. Nitinol U-clips (Medtronic, Minneapolis, Minn) made of a shape-memory alloy eliminate intrathoracic suturing and may reduce operative times. A retrospective review of robotically assisted mitral valve repair surgery was done at East Carolina University, where preoperative, intraoperative, and postoperative data were collected prospectively. The total time for U-clip or suture placement, as well as those for cardiopulmonary bypass, crossclamp, and annuloplasty band placement, were studied. Patients in whom only U-clips were used ("U-clips" cohort) were compared with those in whom only sutures were used ("sutures" cohort). Comparisons between groups were by two-tailed Student t test. Between May 2000 and June 2004, U-clips were used exclusively in 50 patients (mean age 58.4 +/- 13.2 years), and sutures were used exclusively in 72 patients (mean age 56.2 +/- 12.9 years). The mean total time for placement and deployment of U-clips was shorter than for placement and tying of sutures (101 +/- 45 seconds vs 186 +/- 79 seconds, respectively, P < .001). Cardiopulmonary bypass, crossclamp, and annuloplasty band placement times were shorter in the U-clips cohort (144 +/- 50 minutes vs 169 +/- 35 minutes, 105 +/- 30 minutes vs 132 +/- 29 minutes, and 26 +/- 5 minutes vs 40 +/- 10 minutes, U-clips vs sutures, respectively, all P < .01). Significantly shorter times were observed for placement and deployment of U-clips versus placement and tying of sutures, resulting in a reduction in mean band placement time of 14 minutes and significantly shorter cardiopulmonary bypass and crossclamp times in the U-clips cohort. Therefore, use of Nitinol U-clips instead of sutures may allow for significantly faster robotically assisted mitral valve repair surgery.

SELF-CLOSING U-CLIPS FOR INTRACRANIAL MICROANASTOMOSES IN HIGH-FLOW ARTERIAL BYPASS

Self-closing nitinol U-clips (Medtronic, Inc., Minneapolis, MN) have been used to create vascular microanastomoses by vascular surgeons. This device eliminates the need for suture management and knot tying. Therefore, a high-quality interrupted microvascular anastomosis can be obtained in a shorter period of time. This is the first report of a U-clip intracranial arterial microanastomosis for a high-flow extracranial-intracranial bypass using a radial artery graft. A 24-year-old woman with a history of chronic headache was admitted to the National Neurological Institute Carlo Besta after a brain computed tomographic scan revealed a giant serpentine aneurysm of her right middle cerebral artery. Magnetic resonance angiography and four-vessel angiography confirmed the diagnosis and ruled out other lesions. A radial artery graft was used to create a high-flow bypass between the external carotid artery and the postaneurysmal M2 segment of the right middle cerebral artery. Nitinol self-closing U-clips were used for the interrupted intracranial microanastomosis. After intraoperative near-infrared indocyanine green video angiography confirmed the bypass patency, the aneurysm could be trapped. The postoperative course was uneventful. The patient was discharged on the seventh postoperative day and was neurologically intact. Postoperative angiography documented the successful exclusion of the aneurysm and the presence of revascularization of the distal branches of the right middle cerebral artery through the bypass. This case demonstrates the efficacy of U-clips for intracranial microanastomoses.

Self-Closing U-Clip for Intracranial Microvascular Anastomosis: Report of Three Cases

Purpose: Self-closing nitinol U-clips (Medtronic, Inc., Minneapolis, USA) have been used to create vascular microanastomoses by vascular surgeons. This device eliminates the need for suture management, knot tying, and surgical assistance. Therefore, a high-quality interrupted microvascular anastomosis can be obtained in a shorter time.

Complex Bileaflet Mitral Valve Repair (Barlow's) Using the da Vinci Robotic Surgical System

Robotic mitral valve repair (RMVR) is less invasive and potentially more precise. However, RMVR lengthens both cardiopulmonary bypass and arrested heart times. In our initial experience, only posterior leaflet repair and/or annuloplasty were performed. With increasing experience, we have performed more complex bileaflet RMVR. A 50-year-old man presented with severe mitral regurgitation. Transesophageal echocardiography (TEE) demonstrated a complex bileaflet prolapse and preserved left ventricular function. Through a 4 cm working port and with the da Vinci Robotic Surgical System (Intuitive Surgical, Sunnyvale, CA) RMVR was performed. Details of the technique and patient's hospital course are described. The repair comprised closure of clefts between A3 and P3, quadrangular resection of P2, transfer of multiple chords from P2 to A2/A3 and a #38 Cosgrove-Edwards (Edwards Lifesciences, Irvine, CA) band annuloplasty. Nitinol U-Clips (Medtronic, Minneapolis, MN) were used to complete the annuloplasty. Postoperative TEE showed no mitral regurgitation. The patient was discharged on the third postoperative day. Cardiopulmonary bypass and arrested heart times were 3 hours and 29 minutes and 2 hours and 59 minutes, respectively. Complex bileaflet repair of mitral valve with Barlow's disease can be successfully performed with the da Vinci Robotic Surgical System. Long-term follow-up is needed to assess the durability of repair.

Influence of anastomotic techniques in totally endoscopic coronary artery bypass

Beating heart totally endoscopic coronary artery bypass grafting (TECAB) utilizing a computer-enhanced telemanipulation system is a technically challenging procedure. The objective of our study was to compare two different anastomotic techniques. Ten canine beating heart TECAB procedures were performed using Intuitive's daVinci surgical system. Left internal mammary artery (LIMA) to left anterior descending coronary artery (LAD) anastomosis was performed on all subjects. Anastomosis varied between a conventional running suture (8-0 Gore-tex) (group I) and an interrupted nitinol u-clip anastomosis (group II). On-table angiography was then performed to assess graft patency. While internal mammary artery (IMA) mobilization time decreased over the course of the study (p = 0.017), there was no significant difference in ischaemia time, anastomosis time or angiographic assessment between anastomotic techniques. Although operative time in group II was significantly shorter than in group I, this was likely due to the small sample size. There were no differences in anastomotic time or coronary occlusion time. There were also no significant differences in canine weight, IMA mobilization time, lipectomy/pericardiotomy, LAD identification, subxiphoid port placement, stabilizer position, or LAD dissection time between the cases performed with the conventional running suture and the cases performed with u-clips. Interrupted nitinol clip anastomosis or conventional running suture anastomoses are equally favourable in the short term when performing a TECAB procedure.