Arteriotomy closure by glued patch in the porcine carotid artery

Experimental study of sutureless vascular anastomosis with use of glued prosthesis in rabbits

OBJECTIVE

The objective of this study is to explore the feasibility and efficacy of a new technique for sutureless vascular anastomosis, using glued prosthesis, as a sole anastomosis fixation method in rabbits.

METHODS

Ten rabbits were randomly selected to conduct the experiment. Five rabbits underwent direct anastomosis of infrarenal abdominal aorta, with glued prosthesis. In five other rabbits, reconstruction was done by sutured anastomosis. All animals were immediately examined by echo-Doppler for patency of anastomosis. The burst pressure of the glued anastomosis was measured and compared with that of a sutured artery. The animals were euthanized, and tissue samples were taken for histological examination immediately after the experiment.

RESULTS

Compared to conventional anastomoses, sutureless vascular anastomoses required shorter time of creation and significantly reduced blood loss (P<5%). There was no significant difference on the average blood flow through the anastomosis between two groups at the end of surgery. All anastomoses with glued prosthesis, examined by echo-Doppler, were patent at the anastomotic site, except one, which was stenosed immediately after surgery. In the control group, except one with stenosis, all conventional anastomoses were patent. Mean burst pressure at the anastomotic site for sutureless anastomoses was lower than in control group. Macroscopically, the BioGlue did not demonstrate any adhesion to the surrounding tissue as it was covered by the vascular prosthesis. Histological examination showed low-grade inflammatory reaction in glued anastomoses versus no inflammatory reaction at the sutured anastomoses.

CONCLUSION

This technique may provide a feasible and successful alternative in vascular surgery. However, further long-term studies are necessary to elucidate the break pressure and degree of inflammation at the anastomotic site.

Development of poly(trimethylene carbonate) network implants for annulus fibrosus tissue engineering

PURPOSE

Intervertebral disk degeneration is the main cause of chronic back pain. Disk degeneration often leads to tearing of the annulus fibrosus (AF) and extrusion of the nucleus pulposus (NP), which compresses the nerves. Current treatment involves removing the herniated NP and suturing the damaged AF tissue. This surgical approach has several drawbacks. In this study, we designed a biodegradable AF closure system comprising a tissue engineering scaffold, a supporting membrane and an adhesive material, to not only restore the function of the herniated disc but also to promote tissue regeneration.

MATERIALS AND METHODS

Porous scaffolds with precisely defined architectures were built by stereolithography using resins based on poly(trimethylene carbonate) (PTMC) macromers functionalized with methacrylate endgroups. In addition, a porous photo-cross-linked PTMC membrane was developed that can be used to keep the scaffold in place in the AF tissue.

RESULTS

After synthesis and characterization, the components of the implant are glued together and to the AF tissue using a diisocyanate glue based on polyethylene glycol-PTMC triblock copolymers. The adhesion strengths of the materials to each other and to AF tissue were determined in lap-shear tests.

CONCLUSIONS

This study showed that a device for AF tissue engineering can be prepared from PTMC-based scaffolds, membranes and glues.

Coating the wall of an injured intracranial carotid artery during tumor removal with n-butyl-2-cyanoacrylate: technical case report

OBJECTIVE

Carotid artery injury close to the clinoid process is difficult to repair, and is even more so when the vessel is firmly attached to a calcified tumor. We treated a patient with an intraoperative carotid lesion by coating the vessel wall with n-butyl-2-cyanoacrylate (NBCA).

CLINICAL PRESENTATION

A 7-year-old boy was referred to our clinic with a 3-month history of somnolence, apathy, and headache. Neurological examination revealed bitemporal hemianopsia. The cranial magnetic resonance imaging and computed tomographic scans showed a sellar and suprasellar calcified mass with heterogeneous contrast enhancement, a cyst component in the upper part of the tumor displaced upward and back from the mesencephalic and diencephalic structures.

INTERVENTION

The patient underwent a pterional craniotomy. Using a microsurgical technique, the suprasellar part of the craniopharyngioma was removed. In an attempt to dissect the calcified mass from the carotid artery on the right side, the vessel was unintentionally injured, followed by severe bleeding. Temporary occlusion and suturing of the vessel was impossible because of the overlying hard mass. To avoid a permanent occlusion, we decided to coat the injured artery wall with 100% NBCA. For this, 0.5 ml of NBCA was distributed on the surface of the injured segment and surrounding subarachnoid space by injection through a needle. An excellent hemostasis could be obtained immediately after coating. The patient woke up with no new neurological deficits. A digital cerebral angiogram obtained a few days after the procedure did not show vasospasm, stenosis, or pseudoaneurysm in the supraclinoidal segment of the carotid artery. A magnetic resonance angiogram obtained 3 years later showed a normal shape of the internal carotid artery and a stable residual tumor without inflammatory signs. The child is now attending school and is under hormonal therapy.

CONCLUSION

For hemostatic purposes, the technique of coating an injured arterial wall with NBCA may be useful in cases in which a microsuture is impossible and a permanent artery occlusion is unwanted because of a risk of an ischemic stroke. It could serve as a transitory measure until a microsurgical bypass or the balloon test occlusion tolerance allow the trapping of the affected artery.

Coronary end-to-side sleeve anastomosis using adhesive in off-pump bypass grafting in the pig

BACKGROUND

In the exploration of facilitated coronary anastomosis strategies, we assessed a new octylcyanoacrylate adhesive in combination with a modified end-to-side sleeve anastomosis in off-pump bypass grafting in the pig.

METHODS

Sleeve-adhesive anastomoses (n = 20) were evaluated intraoperatively, at 3 days (n = 4), and at 5 weeks (n = 16) in an off-pump, low (< or = 15 mL/min; n = 10) and high flow (approximately 60 mL/min; n = 10) porcine bypass model. All anastomoses were examined by flow measurement, angiography, and histology.

RESULTS

Anastomosis construction took 8.5 minutes (6.7 to 10.2 minutes; median [15th to 85th percentile]). At 5 weeks, all anastomoses were fully patent (FitzGibbon grade A). The adhesive did not cause impaired vessel wall healing, but was surrounded by a focal acute and limited chronic (foreign body giant cells occasionally seen) inflammatory reaction at the adventitial application site.

CONCLUSIONS

Octyl-cyanoacrylate tissue adhesive combined with end-to-side internal mammary to coronary artery sleeve anastomosis construction proved to be feasible, even in low bypass graft flow conditions (< or = 15 mL/min; prothrombotic milieu) in the pig and deserves interest in exploration of facilitated anastomosis strategies in coronary artery bypass grafting.

Sutureless coronary anastomosis with an anastomotic device and tissue adhesive in off-pump porcine coronary bypass grafting

OBJECTIVE

In the search for a facilitated coronary artery anastomosis, we assessed the feasibility of a hybrid anastomosis technique that used a prototype anastomotic device with an extraluminal frame (crinoline-like) and octyl-cyanoacrylate adhesive.

METHODS

During off-pump coronary artery bypass grafting in pigs (n = 8), a left internal thoracic artery-right coronary artery anastomosis was constructed and evaluated during the operation and at 5 postoperative weeks. The anastomosis was examined by flow measurement, angiography, intraluminal cast geometric analysis, and histologic analysis.

RESULTS

Anastomosis construction required 6.2 +/- 1.3 minutes (mean +/- SD). At 5 weeks all anastomoses were fully patent, with minor anastomotic diameter narrowing (median 16%, 15th-85th percentile 16%-26%). After 30-second graft occlusion, median peak hyperemic flow response was 5.0 (15th-85th percentile 4.4-6.5). As a result of complete, streamlining filling of anastomotic wall recesses by neointima formation, more intimal hyperplasia was found in the crinoline-adhesive anastomoses than in sutured control anastomoses. No excessive, lumen-narrowing neointima formation was observed, however.

CONCLUSIONS

The hybrid coronary anastomosis technique was feasible without any need for dedicated application tools. If technical improvements can be realized, the hybrid technique may provide an alternative to manual suturing.