Morphological Differences in the Aorto-iliac Segment in AAA Patients of Caucasian and Asian Origin.

OBJECTIVE: The objective was to quantify aorto-iliac morphology differences between AAA patients of Caucasian and Asian origin. Additionally, the impact of patient demographic characteristics was assessed, which could influence the morphological differences. METHODS: This international multicentre study included two tertiary referral institutions from Europe and one from China. CT scans with 3D reconstruction of 296 patients with infrarenal AAA >5 cm were analysed. Eighteen measurements were recorded from each CT scan and compared between Caucasian and Asian patients. RESULTS: Caucasian patients had longer common iliac arteries (right: 65.0 vs. 33.1 mm, p < .001 left: 65.0 vs. 35.2 mm, p < .001), longer aneurysm neck (33.0 vs. 28.4 mm, p < .001), greater aneurysm to aortic axis angle (153.0° vs. 142.2°, p < .001), and longer combined aorto-iliac length (195.7 vs. 189.2 mm, p < .001). However, Asian patients had a longer infrarenal abdominal aorta (152.0 vs. 130.0 mm, p < .001), longer AAA (126.2 vs. 93.0 mm), and greater linear distance from renal artery to aorto-iliac bifurcation (143.6 vs. 116.0 mm, p < .001). Caucasian patients had a larger inner common iliac artery diameter (right: 16.0 vs. 14.9 mm, p < .001, left: 16.0 vs. 15.2 mm, p < .001), larger inner exernal iliac artery diameter (right: 9.0 vs. 7.5 mm, p < .001 left: 9.0 vs. 7.7 mm, p < .001), and larger inner common femoral artery diameter (right: 10.0 vs. 5.9 mm, p < .001 left: 10.0 vs. 6.1 mm, p < .001). No difference was observed in AAA transverse diameter (62.0 vs. 63.1 mm, p = .492). CONCLUSION: The results showed that aorto-iliac anatomy in Caucasians differs significantly from Asians, particularly in the length of the common iliac arteries and infrarenal abdominal aorta, and in the transverse diameter of the common, external iliac, and common femoral arteries. Therefore, the exact criteria for stent graft design are dependent on the racial origin of the patient.

Prevalence of Non-thrombotic Iliac Vein Lesions in Patients with Unilateral Primary Varicose Veins.

OBJECTIVES: A role of non-thrombotic iliac vein lesions (NIVLs) in the development of primary varicose veins (PVVs) has not been studied. It seems that intravascular ultrasound (IVUS) is the most accurate method to diagnose these lesions. The aim of the study was to investigate the association between the presence of NIVLs and PVVs and the frequency of NIVLs in asymptomatic and PVV limbs. DESIGN: This was an observational study. MATERIALS: Thirty-three patients with unilateral PVV and great saphenous vein incompetence who were qualified for surgical treatment were analyzed. Nineteen patients (57%) presented with varicose veins on the right side. METHODS: During varicose vein surgery, IVUS of the iliac veins and the inferior vena cava was performed. In all patients the iliocaval outflow was interrogated by IVUS in both the limb with and without PVVs. The PVV side was accessed through the surgically exposed sapheno-femoral junction and the non-PVV side was accessed by an ultrasound guided percutaneous puncture of the common femoral vein. In both the common iliac (CIVs) and the external iliac veins (EIVs) the minimal and reference lumen area were measured and the percentage stenosis calculated. RESULTS: There were no intra- or post-procedural complications. The minimal lumen area (MLA) was smaller and the stenosis of the CIV was greater on the left side than the right: median 57 and 108 mm(2) (p = 0.001) and 69 and 34% (p < 0.001), respectively. However when the PVV and non-PVV sides were compared, no statistically significant differences of MLA or stenosis of the CIV were found: 88 and 67 mm(2) (p = 0.38) and 44% and 51% (p = 0.40), respectively. With regard to EIVs, no statistically significant differences in either MLA or stenosis between the left and right and PVV and non-PVV sides were found. The frequency of ≥50% stenosis of CIV and EIV in the PVV limbs and the non-PVV limbs was 42% and 48% and 51% and 39%, respectively. CONCLUSIONS: NIVLs are common in patients with PVV but do not seem to be associated with the presence of ipsilateral PVV.

Dielectric relaxation of a protein-water system in atherosclerotic artery wall.

Measurements of the dielectric properties of healthy and atherosclerotic human artery tissues were made in the frequency range of 100 Hz-100 kHz and temperatures from 22 to 260 degrees C. The temperature dependencies of the dielectric parameters for healthy tissues reveal distinctively the temperature ranges corresponding to the release of water up to 200 degrees C and the decomposition processes of elastin and collagen, above this temperature. The influence of atherosclerosis on the dielectric properties of artery tissues is significant in the whole temperature range. The relative permittivity for atherosclerotic tissues at the same temperature is much lower than for the healthy tissues. This suggests, that the polarization in atherosclerotic tissues due to protons hopping between a smaller number of sites than in healthy tissues, as a results of the thermal degradation of collagen-water. The data obtained above 200 degrees C indicate that the atherosclerosis induces the higher physico-chemical changes in the collagen when compared to elastin.

Restenosis after carotid endarterectomy: incidence and endovascular management.

SUMMARY: Surgical procedures designed to restore vascular patency for a recurrent stenosis following carotid endarterectomy (CEA) are burdened with technical difficulties as well as with the possibility of serious neurological complications. An endovascular approach employing transluminal percutaneous angioplasty and stenting (PTAS) is a promising solution to these problems. We aimed to evaluate the incidence of carotid artery restenosis following CEA, and to evaluate the safety and efficacy of treating post-CEA restenosis with an endovascular technique (PTAS). One hundred and two patients who underwent CEA for symptomatic and asymptomatic stenosis were included in the analysis. Clinical and sonographic follow-up examinations identified carotid artery restenosis in 16 patients, who fulfilled our criteria for endovascular treatment. Carotid PTAS was performed on symptomatic patients with a stenosis over 60% of the artery lumen (n=7) and in asymptomatic patients with a stenosis over 80% (n=9). The post-PTAS patients were evaluated by duplex sonography every three months over a 24 month follow-up period for evidence of restenosis. The cumulative incidence of post-CEA carotid restenosis qualifying for PTAS was 9.3% during an average 12-month follow-up interval. The average time from CEA to carotid PTAS was 11 months. All 16 endovascular procedures were technically successful. All of the carotid arteries were widely patent following PTAS. There were no immediate perioperative complications. One patient died two days after carotid PTAS from a cerebral hemorrhage. Thirteen of the 16 patients remained asymptomatic and had no sonographic evidence of significant restenosis during the 24- month post-PTAS follow-up period. One patient developed a symptomatic 80% restenosis proximal to the stent six months after carotid PTAS. Another patient developed an asymptomatic 60% restenosis proximal to the stent at 24 months. One patient was lost to follow-up. Following CEA, there is a significant risk of developing a symptomatic or high-grade carotid artery restenosis requiring correction. Endovascular treatment (PTAS) of a recurrent stenosis after CEA is a safe and effective alternative to repeat carotid surgery.

The influence of cryopreservation on changes in diameter and compliance of allografts in an animal experimental model.

OBJECTIVE: The purpose of this study was to analyze the influence of cryopreservation on changes in diameter and compliance of allografts. METHODS: Sixty aortic allografts implanted in situ in rats were analyzed. The animals were divided into four groups that received fresh or cryopreserved isogenic (Lewis to Lewis) grafts, or fresh or cryopreserved allogenic (Lewis to DA) grafts, respectively. The diameter and compliance of the grafts were then visually evaluated with the digital video camera recorder after 15, 30, 60, 90 and 120 days. RESULTS: Gradual increase in diameter and decrease in compliance in case of all allogenic and cryopreserved isogenic grafts were observed. The observed changes in cryopreserved grafts were smaller when compared with fresh grafts, however, the differences did not reach statistical significance. CONCLUSION: Cryo preservation does not protect allografts from stiffening and dilatation.

Cryopreserved arterial allografts in the treatment of prosthetic graft infections.

AIM: The purpose of this study was to evaluate the effectiveness of cryopreserved arterial allografts in the management of prosthetic graft infection. MATERIAL AND METHODS: Over a 5-year period 45 patients with infection of prosthetic vascular grafts were treated. There were 39 intra-abdominal infected grafts (group I) and six extra-abdominal infected grafts (group II). Treatment consisted of total graft removal and in situ or extra-anatomic implantation of cryopreserved arterial allografts. Six patients were operated on as an emergency. Four patients presented with aorto-enteric fistula. Follow-up ranged from 30 to 78 months. RESULTS: There were six in-hospital deaths and two additional patient deaths during follow-up, yielding an overall mortality rate of 18%. Six patients died due to complications directly related to infection or insertion of an allograft. Combined short and long-term mortality rate was much higher in patients operated on as an emergency (67%) compared to elective cases (11%). Patients with aorto-enteric fistula had the highest mortality rate (75%). Primary and secondary 3-year allograft patency rates for group I were 84 and 94%, respectively and for group II were 60 and 80%, respectively. CONCLUSIONS: Aortic allografts are useful in the treatment of infection of major vascular prosthetic grafts, except for patients with aorto-enteric fistula. Patients with infection of the prosthetic graft should be promptly assessed for graft removal, since results of elective surgery are much better than results of emergency procedures.

The mechanical properties of fresh and cryopreserved arterial homografts.

OBJECTIVES: To assess the effect of cryopreservation on the elasticity and compliance of arterial allografts. MATERIALS AND METHODS: Iliofemoral segments of arteries and veins harvested from multiorgan donors were divided into two groups: fresh-control, tested for 24 hours after harvesting, and cryopreserved in liquid nitrogen after pretreatment with 20% dimethylsulphoxide and stored for an average time of 22 days. Vessel wall elastic properties were evaluated from the stress-strain relationship in a specially designed test cell fixed to the Instron Universal Testing Machine. RESULTS: The elastic modulus of the artery control group (1.54+/-0.33 MPa, n=20) was not significantly different from the cryopreserved group (1.69+/-0.61 MPa, n=15). Similarly, values for unfrozen veins (3.11+/-0.65 MPa, n=47) were not significantly different from those of frozen samples (2.71+/-0.85 MPa, n=38). Control compliance (6. 86+/-1.79x10(-5)%/Pa, for arteries; 3.84+/-0.81x10(-5)%/Pa, for veins) was similar to that of the cryopreserved group (6.66+/-1. 80x10(-5)%/Pa, for arteries; 4.16+/-1.21x10(-5)%/Pa, for veins). CONCLUSIONS: Cryopreservation maintains the important elastic properties of arterial and venous allografts during average storage time of 22 days.

Sutureless intraluminal graft for repair of high abdominal aortic aneurysm.

The aim of our study was experimental and clinical assessment of bifurcated grafts with ring on its main branch made of the same polyester as the prosthesis. This type of prosthesis facilitates quick anastomosis with the aorta through tying the aortic wall on the ring using a polyester tape. Experimental studies carried out on 18 pigs demonstrated good healing up of such a graft. The prosthesis was used for surgery in 8 patients with abdominal aneurysm which required clamping the aorta above renal arteries. The prosthesis was found to facilitate and accelerate making the proximal anastomosis, diminish the amount of blood loss, and reduces the time of the surgery, especially the time necessary for clamping the aorta above renal arteries which prevents renal ischaemia.

[The importance of excision of the first thoracic rib and accessory cervical rib in the treatment of deep venous thrombosis of the upper extremities]. / Znaczenie usuniecia pierwszego zebra piersiowego i dodatkowego zebra szyjnego w leczeniu zakrzepicy zyl glebokich konczyny górnej.

This paper presents 15 cases of deep venous thrombosis of the upper extremity as a complication of previously asymptomatic thoracic outlet syndrome. The diagnosis was based on clinical examination and phlebography. To achieve prompt recanalisation of the vein streptokinase was used. Fibrinolytic treatment was followed by surgical treatment carried out 6 to 8 weeks after resolution of acute symptoms. The surgery consisted of excision of first rib and accessory cervical rib when present through the axillary approach. In 73% of cases complete lysis of the thrombus was achieved which was confirmed by phlebography and resolution of symptoms of venous hypertension.

[Thrombophlebitis profunda in patients after conventional and laparoscopic cholecystectomy]. / Thrombophlebitis profunda bei Patienten nach der konventionellen und laparoskopischen Gallenblasenentfernung.

The purpose of this study was to compare the incidence of deep venous thrombosis (DVT) in patients undergoing uncomplicated laparoscopic cholecystectomy and in whom conversion to laparotomy was required. Using the Duplex Doppler examination, we found higher incidence of DVT in patients who required conversion than in those who did not (47 vs 58%). Prolonged prophylaxis with low-molecular weight heparin should be considered in these patients.

[Investigations on the pathogenesis of primary varicose veins]. / Badania nad patogeneza pierwotnych zylaków konczyn dolnych.

The data from the clinical course and epidemiology of primary varicose veins of lower limb suggest that sex hormones can directly influence the development of the disease through their intracellular receptor localised in cells of venous wall. The purpose of this study was to determine the stereometric differences in the structure of healthy and varicose veins of lower limb and to determine the presence and localisation of oestrogen and progesterone receptors in the cells of vein. The segments of greater saphenous vein obtained from the 8 women operated for varicose vein were used for the study. The segments of the greater saphenous vein obtained from 8 women that underwent femoro-popliteal venous bypass procedure were used as control group. The vein samples for stereometric analysis were preserved in Buin's solution, embedded in paraffin and then evaluated with automatic analyser MagiCal. To determine the presence of oestrogen and progesterone receptors the immunohistochemic analysis LAB with monoclonal antibodies produced by DAKO was used. The decreased smooth muscle fraction in venous wall, thickening of adventitia, the change of the smooth muscle cells to stroma cells ratio in the muscular layer of venous wall and change of muscular layer to adventitia ratio were observed in varicose veins in comparison with control group. The oestrogen receptors were found in the nuclei of the smooth muscle cells and endothelium. The progesterone receptors were localised in nuclei of smooth muscle cells and cells of subendothelial layer. It seems that quantitative analysis of sex hormones receptor in the venous wall could be useful in the determination of patients with increased risk of the development of primary varicose veins.

[Preoperative autotransfusion and hemodilution and its value in reconstructive vascular surgery]. / Autotransfuzja i hemodilucja przedoperacyjna i jej znaczenie w operacjach rekonstrukcyjnych tetnic.

Autotransfusion and haemodilution are the most safe and well known methods of blood protection in patients planned for vascular operations. During reconstructive vascular surgery autotransfusion with hypovolemic or normovolemic haemodilution were used. In the I group of patients hypovolemic haemodilution was done. In the II group of patients vascular bed was filed up with Ringer solution or with 6% solution of hydroxyethyl starch. The type of haemodilution and its influence on haemodynamics were estimated. Investigations were done by echocardiograph: ATL ULTRAMARK 8. It was concluded that the most effective are autotransfusion and normovolemic haemodilution with filing up vascular bed with Ringer solution.