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V Chovanec

Publications and source records attributed to V Chovanec.

8 recordsLinked to original sources
PubMed2006

Temporary liver blood-outflow occlusion increases effectiveness of radiofrequency ablation: an experimental study on pigs.

AIM: To evaluate the feasibility of liver blood outflow (LBOF) occlusion and its impact on the effectiveness of radiofrequency ablation (RFA). METHODS: The experiment was performed on 10 pigs. The animals were divided into groups A and B according to RFA protocol. In group A (n=5) the RFA time was that taken to reach the target temperature of 105 degrees C, whereas group B (n=5) had a constant RFA temperature of 105 degrees C and constant time of 8min. The liver blood flow (LBF) was quantified using Doppler ultrasonography before LBOF occlusion and after that. RFA were performed using an expandable 3cm RF needle. Two liver ablations created in different liver lobes were compared; the first ablation was created before balloon inflation and the second one was created under LBOF occlusion. The time required for RFA procedure, liver ablation volumes, shape and microscopic changes of the thermoablated zones were recorded. RESULTS: The LBF dropped significantly in all liver vessels after balloon inflation. The volume of the ablated area was 8.2+/-2.2cm(3) and increased significantly after LBOF occlusion to 17.4+/-3.8cm(3) (p<0.001), in group A. A significant enlargement of the ablated area with occluded LBF was registered in group B, it was 6.7+/-2.8cm(3) versus 19.4+/-1.8cm(3) respectively (p<0.01). CONCLUSIONS: Temporary LBOF occlusion led to a significant reduction in liver blood flow, enlargement of the thermoablated area volume and homogeneity of the coagulated zones.

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PubMed2006

[Penetrating aortic ulcers--case report on endovascular therapy].

We report our experience with two cases of endovascular treatment of penetrating aortic ulcers (PAU). The first patient was a 71-year-old woman with 30 mm width aortic ulcer accompanied by intramural hematoma of the descending thoracic aorta. The second patient was an 80-year-old obese woman with 50 mm pseudoaneurysma of the abdominal aorta, which was result of PAU. Both patients were successfully treated by means of tubular stentgraft, implanted from surgical cut down of the right femoral artery. Penetrating aortic ulcer represents localized, potentially lethal pathology of the aorta. Together with dissection and intramural hematoma belongs among the acute aortic syndromes. During nature course PAU can progress to the acute classic dissection, pseudoaneurysma or rupture of the aorta. It is principally disease of elderly hypertensive patients. Early diagnosis and appropriate therapy improves prognosis of patients with PAU. Open surgical repair with synthetic graft has been the gold standard of treatment but endovascular therapy is an attractive option in risk elderly patients. It seems to be a safe, effective treatment but stability of results of this method should be proved.

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PubMed2006

[Ischemic disease of the lower extremities versus depression symptoms and quality of life].

BACKGROUND: The study has three main aims: 1. it evaluates occurrence of depression symptoms in patients with peripheral arterial occlusive disease (PAOD), 2. it evaluates global quality of life (QoL) in patients with PAOD and 3. it evaluates effect of age and stage of PAD on seriousness of depression symptoms and on the QoL in patients with PAOD. PATIENTS AND METHOD: the study is local, prospective and cross-sectional. It was carried out at the 2nd Internal Clinic of University Hospital in Hradec Králové. Data were obtained during the year 2006. METHODS AND RESULTS: The total number of respondents with PAOD was 42 (28 male, 14 female). The average age of all respondents with PAOD was 65.4 years and age range was 45-79 years. The evaluation of occurrence of depression symptoms in patients with PAOD was performed by means of self-assessment Zung-SDS and evaluation of QoL in patients with PAOD was performed by means of Czech version of international generic European Quality of Life Questionnaire-EQ-5D Version. Statistical significance was determined by means of analysis of variance. Main The mean SDS index certifies the presence of signs of minimum or light depression in patients with PAOD. The QoL in patients with PAOD is on the low level. The above-mentioned aspects proved statistically significant dependence of QoL in patients with PAOD on depression (p<0.001), on age (p<0.01) and on stage of PAOD (p<0,01). We proved statistically significant dependence of depression in patients with PAOD on age (p<0.01) and on stage of PAOD (p<0.01). CONCLUSIONS: The results show the existence of the association between PAOD and depression symptoms with its negative effect on QoL in patients.

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PubMed2004

[Diagnosis of spontaneous arteriovenous fistula complicating aortoiliac aneurysm using spiral CT. Report of 3 cases].

Acute spontaneous arterio-venous fistula complicating atherosclerotic abdominal aortic aneurysm (AAA) is rare. This life-threatening setting is observed in 1-2% of all AAAs and 2-4% of ruptured of AAAs. The triad of abdominal or lower back pain, pulsatile abdominal mass, and continual abdominal machinery-like bruit is seen only in half of cases. Currently, CT angiography is a noninvasive technique which enables a rapid and exact preoperative diagnosis. The authors describe three cases of aortoiliac aneurysm complicated by an acute arteriovenous fistula which were diagnosed using spiral CT.

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PubMed2000

Autologous vein stent-graft: feasibility study.

PURPOSE: To evaluate expandable stents healed into vein wall as autologous vein stent-grafts for endoluminal grafting. MATERIALS AND METHODS: Balloon expandable stents were placed into external jugular veins of eight dogs. Stent and vein patency was followed by ultrasonography. Five weeks after stent placement, jugular veins with endothelialized stent were harvested. The autologous vein stent-grafts were divided into two groups. In group A, autologous vein stent-grafts (n = 3) were placed immediately into Baker solution for microscopic examination. In group B, autologous vein stent-grafts (n = 3) underwent mechanical manipulation; they were compressed, mounted on angioplasty balloon, pushed through a 9-F sheath and dilated. The autologous vein stent-graft endothelialization and changes after mechanical manipulation were evaluated by light and electron microscopy. RESULTS: Stent placement was successful in seven dogs. One stent migrated into the pulmonary artery. One well placed stent was damaged by compression dressing and thrombosed. At 5 weeks, gross and microscopic examinations revealed the autologous vein stent-grafts were fully covered by a 0.115- +/- 0.036-mm-thick neointimal layer. Small wall thrombus was observed in one autologous vein stent-graft. Repeated manipulations did not result in any intimal damage or stent loosening in the autologous vein stent-grafts. CONCLUSION: Expandable stents healed into a vein have potential to be used as autologous vein stent-grafts for endoluminal grafting without risk of disruption during percutaneous transcatheter introduction.

Animals↗
PubMed2000

[Preservation of venous grafts].

The objective of the work was to find an optimal preservation medium for short-term preservation of venous grafts which could be subsequently used to line metal stents. The external jugular vein of dogs (n = 15) was removed surgically, divided into portions and immersed into preservation media. For hypothermic preservation (+4 degrees C) solutions of Optisol (Chiron, USA), University of Wisconsin (Baxter, USA), Eurocollins (Fresenius, GFR) and saline (Bieffe Medital, Italy) were used. For normothermic preservation (+37 degrees C) in an atmosphere with 5% CO2 Dulbecc's medium for tissue cultures (Sigma, USA) was used. During hypothermic preservation the specimens were kept for 24 hours, 3 and 7 days, during normothermic preservation in Dulbecc s medium also for 24 hours, 3 and 7 days. The specimens were evaluated by light microscopy and raster electron microscopy. The results revealed that minimal changes on the endothelia of venous grafts occurred during normothermic preservation in Dulbecc's medium where after 7 days the endothelium did not become detached and the vitality of cells did not change. During hypothermic preservation the solution of Wisconsin University proved most suitable. By addition of 5% human albumin to this solution it proved possible moreover to reduce pyknosis of the endothelial cell nuclei. The specimens kept in saline displayed deformities of the nuclei, oedema and loss of endothelia incl. incipient oedema of the cellular wall already after 24 hours of hypothermic preservation. The authors consider the use of this solution unsuitable for preservation.

Animals↗
PubMedDate not supplied

Endovascular brachytherapy in the prevention of vascular restenosis.

PURPOSE: To evaluate the technical feasibility and efficacy of endovascular brachytherapy for prophylaxis of restenosis after femoropopliteal percutaneous transluminal angioplasty (PTA). MATERIALS AND METHODS: Ten patients with recurrence of stenosis in the femoropopliteal region underwent PTA followed by endovascular irradiation with Iridium-192 a high-dose rate after-loading technique. We used a single fraction of dose 12 Gy given in 3 mm from the source axis in the stenotic vessel segment. RESULTS: During follow-up of 59-580 days restenosis occurred in four patients 111, 460, 472 and 580 days after irradiation. All other patients are without restenosis. No radiation-associated side effects were observed. CONCLUSIONS: Endovascular brachytherapy of restenosis in the femoropopliteal region is technically feasible, and may be done as a part of the PTA. These encouraging results open the possibility of reduction of restenosis by the present method.

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