[Effect of biological glues on vascular wall in an experimental model of aortic dissection]

INTRODUCTION

The use of biological glues and their application between the two dissection layers and into the anastomosis region is a common integral part of surgical management of thoracic aortic dissections.

AIM

The aim of the experimental study was to assess and evaluate histopathological changes of vascular wall following deposition of the following three types of glue--GRF, Tissucol, Bioglue, based on qualitative and quantitative parameters. The secondary aim of the study was to assess dynamics of these changes depending on the glue effect duration and to formulate expected behaviour of the vascular wall during the time beyond the experimental period.

METHODOLOGY

The dissection model was performed with pigs of the same gender and age, assigned to four groups. Different glues were used to close artificial infrarenal aortic dissections in Group 1-3, while direct suturing and no glue was used to close false lumini in Group 4. Samples of the dissected aorta were then collected at Month 1, 6 and 12 and then histologically examined.

RESULTS

Upon assessment of the whole group of qualitative and quantitative parameters, the most significant changes in the smooth muscle histological picture were observed with the use GRF glue. The smooth muscle changes following the Bioglue application and, in particular, Tissucol glue application, are similar to changes observed in Group 4, where no glue was used.

CONCLUSION

Based on the results, the authors present a hypothesis that, in a long-time horizont, vascular wall destructions, eventually redissections, are likely to occur more frequently in patients, in whom GRF glue is used.

[Intraarterial peroperative thrombolysis in therapy of the acute limb ischemia]

Acute limb ischemia is serious situation, jeopardizing limb salvage, causing embolization or thrombosis of the native arteries or vascular graft. Immediate surgical revascularization with balloon thromboembolectomy is indicated in patient with acute ischemia stage IIB of the Rutherford classification. Unfortunately, operative thromboembolectomy is frequently incomplete, with persistent thrombus remaining in the majority of patients. Residual thrombus compromises the clinical outcome, leading to poor revascularization and an increased risk of tissue loss. On depending of amount of the residual thrombus after surgical thromboembolectomy, we can choose one of the three options of intraoperative thrombolysis. This article summarized indication and technical realisation of intraoperative thrombolysis and describe cause report of the first patient treated with this method in our country. The combined use of intraoperative thrombolytics following mechanical thromboembolectomy is safe and efficacious method in patients with acute vascular occlusion.

[Clinical experience with cold-preservation of venous and arterial allografts. long-term outcomes]

INTRODUCTION

Venous and arterial allografts extend the possibilities of peripheral arterial disease as well as vascular prosthesis infections treatment.

MATERIAL AND METHODS

Between 10/1997 and 1/2009 we used 112 allogeneic vessels (30 arteries, 82 veins) in 104 patients. Venous allografts were used for 82 reconstructions in 75 patients (M/F 41/34, aged 41-85 years, median 66 years) with critical limb ischemia and no suitable autogenous venous material. Arterial allografts were used in 9 patients (M/F 8/1, aged 56-77 years, median 63 years) with aortoiliac prosthetic infections or mycotic abdominal aortic aneurysms and in 20 transplanted patients (M/F 11/9, aged 32-67 years, median 56 years) with aortoiliac atherosclerotic disease.

RESULTS

Patients survival rate after allovenous bypasses was 92% at 1 year and 78% at 3 years. Limb salvage rate was 67% at 1 year and 53% and 3 years. Secondary patency rate was 48% at 1 year and 27% at 3 years. Patient survival rate after alloarterial bypasses was 86% at 1 year and 69% at 3 years. No signs of arterial grafts aneurysmal formation and no need for secondary intervention of any arterial reconstruction was observed during the follow up period in any patient after alloarterial transplantation.

CONCLUSIONS

Cold-stored venous and arterial allografts are suitable alternative conduits for limb salvage procedures, vascular prosthesis infections as well as for arterial reconstructions in transplanted patients.

[Dual kidney transplantation]

Despite the increasing demand for organs for transplantation, the number of cadaveric donors remains stable and waiting time for transplantation is gradually getting longer. In addition to the options of using kidneys from living donors and those of non heart-beating donors (NHBD), an alternative approach is transplantation of both kidneys from adult marginal donors who would otherwise be considered unsuitable for single-kidney donation. Dual kidney transplantation involves the use of both kidneys from a marginal donor for a single recipient without the recipient having to cope with the drawbacks of a limited number of functioning nephrons. Normally. these kidneys would be excluded from the transplantation program and remain unused. The submitted presentation provides information on donor and recipient selection criteria and describes the course of the first dual kidney transplantation in an adult recipient in the Czech Republic.

[First experience with PTFE mesh prothesis in surgery of arteriovenous access]

The authors present their initial experience with implantation of external porous PTFE prosthesis in transpositioning of the basilic vein in brachiocephalic fistules in 5 patients and in the management of radiocephalic fistules in 4 subjects during, operated from October 2006 to April 2007. Implantation of the external porous PTFE prosthesis in venous transpositions to form AVFs is aimed at prevention of pseudoaneurysms formation, as well as at prevention of development of intimal hyperplasias. The external prosthesis implantation is indicated in aneurysmoraphies, where the venous wall is weakened as a result of its suturing, which makes it predisposed for development of a new pseudoaneurysm.

[Experimental use of the peritoneal graft as a vascular prosthesis]

INTRODUCTION

The parietal peritoneum appears to be a suitable material for the vascular system reconstructions.

AIM

The aim was to assess and compare thrombogenicity and ability for endothelization of the mesothelial and submesothelial side of the parietal peritoneum in the canine venous system.

MATERIAL AND METHODOLOGY

EXPERIMENTAL ANIMALS

canis familiaris (n = 13), half-breeds of both sexes, aged between 1 and 2 years, weighting 15-25kgs, underwent authological transplantations of the peritoneal grafts with the mesothelial side in the lumen- the group M (n = 5) and with the submesothelial side in the lumen the group S (n = 5). In the control group K (n = 3) a part of the venous wall was used as a graft and was affixed back to its original place. The bioptic samples collected on the 10th, 20th, 30th and 40th postoperative day (POD) were stained using the HE staining, NADPH-d and imunohistochemically on the intermedial filaments. The endothelization rate of the peritoneal graft was measured using morphometry and the trombogenicity was assessed peroperatively.

RESULTS

In none of the trial groups a presence of thrombi was detected peroperatively. In the first trial group (group M), the onset of the peritoneal graft epithelization (reaching 20%) was recorded on the 10th POD. The endothelization process was completed on the 30th POD in this trial group. In the second trial group (group S), the peritoneal graft epithelization reaching 10% was recorded on the 10th POD. The process was completed on the 40th POD. In the third trial group K, no endothelial changes were recorded during the experiment.

CONCLUSION

Both sides of the peritoneum do not show signs of thrombogenicity and possess ability for endothelization.

[Histologic changes in the jejunal wall after autotransplantation in a dog]

INTRODUCTION

Damages to the small intestinal wall resulting from ischemic-reperfusion changes, represent common complications of the clinical transplantation of the small intestine.

AIM

Evaluation and quantification of the histological changes in the jejunal wall following its autotransplantation in a dog using the scale according to Park.

MATERIAL AND METHODS

In dogs (n = 8), mongrel of both sexes, aged from 6 months to 2 years, weighting from 10 to 25 kgs, a resection of the jejunum followed by its autotransplantation was performed. At the time of the jejunal harvest, then after one-hour-long cold ischemia, 20 minutes after its reperfusion and then the 10th and the 20th day after the transplantation, bioptic samples of the whole jejunal wall were taken to be examined histologically. After being stained with hematoxyllin-eosine, the samples were evaluated according to the Park grading system.

STATISTICS

The severity of the jejunal wall damage at the respective biopsy samples collection times was evaluated using the t-test for two dependent samples.

RESULTS

After an hour-long cold ischemia, signs of increasing damage to the intestinal wall were observed, when compared to the peroperative sample (0 +/- 0) up to the degree 0.68 +/- 0.5 of the Park grading schema (p < 0.05). This damage degree increased 20 minutes after the reperfusion up to the value of 4 +/- 0 (p < 0.05). On the 10th and the 20th day a practically normal histological picture of the jejunal wall was observed. The histological changes in both cases were graded 0.38 +/- 0.5 (p < 0.05).

CONCLUSION

Maximum histological changes following the autotransplantation of the small intestine with an hour-long cold ischemia were observed 20 minutes after the reperfusion. After 10 postoperative days, a practically normal histological picture of the small intestinal wall structure was observed. It remained unchanged even on the 20th postoperative day.