Regional differences in aorta of goat (capra hircus).

Regional differences in the aortic wall are important in explaining the physicomechanical properties and disease distribution in this artery. The goat is a suitable model for studying cardiovascular disease, but the regional features of its aorta are scarcely reported. The purpose of the study was therefore to describe the regional differences in the wall of its aorta. Sixteen healthy adult male domestic goats (capra hircus) were euthanised with intravenous sodium pentabarbitone and specimens obtained from the ascending, arch, each vertebral level of descending thoracic, and various segments of abdominal aorta. The specimens were fixed in 10% formaldehyde solution and routinely processed for paraffin embedding. Seven micron thick sections were stained with Mason's Trichrome and Weigert Resorcin Fuchsin stains. Light microscopic examination revealed that the aortic wall consists of tunica intima comprising endothelium, subendothelial zone and internal elastic lamina, media, and adventitia. Endothelium comprises flat and round endotheliocytes. The population of round cells declines as the internal elastic lamina increases in prominence caudally. Tunica media in ascending, arch, and proximal thoracic aorta comprises two zones: namely a luminal elastic and adventitial musculo-elastic zone, in which muscle islands interrupt some elastic lamellae. These islands progressively diminish caudally until by the eleventh thoracic vertebra they are only patchy. Beyond this point and in the abdominal aorta they are absent and tunica media consists of regular concentric elastic lamellae. Tunica adventitia, on the other hand, increases in thickness and elastic fibre content caudally. Regional variations exist in all three layers of goat aorta. The nature of these differences suggests that they are related to haemodynamic factors. Furthermore, the variations may form the basis for regional differences in physicomechanical strength and disease distribution along the aorta.

Carotid clamping time as a risk factor for early restenosis after carotid endarterectomy.

OBJECTIVE: The aim of our study was to identify risk factors for early restenosis after carotid endarterectomy (CEA). METHODS: Prospective follow-up of 497 primary CEAs was performed at 3, 6, 12 and 24 months by clinical assessment and duplex ultrasound to identify > or = 50% restenosis. RESULTS: Early restenosis occurred in 71 (14.3%) patients. By univariate analysis high carotid clamping time (CCT) (p = 0.002) and absence of shunt use (p = 0.03) were related to early restenosis. High CCT was the only independent predictor of early restenosis in a forward stepwise logistic regression model (OR = 2.25; CI 1.2-4.1; p = 0.008). CONCLUSIONS: Carotid clamping time may be a novel risk factor for early restenosis.

mtDNA analysis of Nile River Valley populations: A genetic corridor or a barrier to migration?

To assess the extent to which the Nile River Valley has been a corridor for human migrations between Egypt and sub-Saharan Africa, we analyzed mtDNA variation in 224 individuals from various locations along the river. Sequences of the first hypervariable segment (HV1) of the mtDNA control region and a polymorphic HpaI site at position 3592 allowed us to designate each mtDNA as being of "northern" or "southern" affiliation. Proportions of northern and southern mtDNA differed significantly between Egypt, Nubia, and the southern Sudan. At slowly evolving sites within HV1, northern-mtDNA diversity was highest in Egypt and lowest in the southern Sudan, and southern-mtDNA diversity was highest in the southern Sudan and lowest in Egypt, indicating that migrations had occurred bidirectionally along the Nile River Valley. Egypt and Nubia have low and similar amounts of divergence for both mtDNA types, which is consistent with historical evidence for long-term interactions between Egypt and Nubia. Spatial autocorrelation analysis demonstrates a smooth gradient of decreasing genetic similarity of mtDNA types as geographic distance between sampling localities increases, strongly suggesting gene flow along the Nile, with no evident barriers. We conclude that these migrations probably occurred within the past few hundred to few thousand years and that the migration from north to south was either earlier or lesser in the extent of gene flow than the migration from south to north.

[Simple vs bifurcated graft operations in patients with abdominal aortic aneurysm]. / Proteza prosta vs proteza rozwidlona w operacjach tetniaków aorty brzusznej.

We analysed 148 patients treated surgically from 1992-1997 because of abdominal aortic aneurysm (AAA). All patients were divided into two groups: group I--118 (79.7%) patients operated with the implantation of the straight graft and group II--30(20.3%) with the bifurcated graft. The aim of the study was to analyse early (30 days after operation) complications in both groups. The mortality rate was 8.5% for group I and 26.7% for group II. The mortality was also analysed according to AAA symptoms (asymptomatic, symptomatic and ruptured). The death rate in asymptomatic patients from group I was 1.1% versus 13.3% in group II. In symptomatic patients the difference was not statistically significant--20% in group I versus 22.2% in group II. The mortality rate in patients with ruptured AAA was 50% for group I and 66.7% for group II. The early morbidity rate was significantly higher in the second group(p < 0.05) although coexisting diseases were similar for both groups. According to our material we conclude, that operation of AAA should be finished in abdomen if there is only technical possibility. It is especially important for patients with ruptured AAA.

[Complication risk after abdominal aortic aneurysm operations]. / Ryzyko powiklan pooperacyjnych tetniaków aorty brzusznej.

Between 1992-1997 185 patients were treated in our Department because of abdominal aortic aneurysm (AAA). The aim of the study was the evaluation of frequency of hospital mortality (30 days) in patients treated because of AAA. One hundred forty eight (80%) patients were operated on and 37 (20%) were treated classically. The surgical group of 148 patients were divided into three parts: group I: 106 patients with asymptomatic AAA, group II: 24 patients with symptomatic AAA and group III: 18 patients with ruptured AAA. Straight graft was performed in 118 patients (79.7%) with hospital mortality rate 8.5% and bifurcated graft implanted in 30 patients with mortality rate 26.7%. Analysis of our material allowed to find that hospital mortality was in group I: 2.8%, group II: 20.8% and in group III: 55.6%. The main cause of deaths in patients from groups I and II was myocardial infarction and hypovolemic shock in group III. The most common postoperative general complications were cardiac and pulmonary and were significantly more often in group III (p < .05). Other not significantly registered postoperative complications as renal insufficiency were also more common in patients from group III. Analysis of our material revealed that patients with abdominal aortic aneurysm should be operated selectively, when aneurysm diameter reaches 50 mm, and optimal method is straight graft which allows to reduce to minimum postoperative complications.

[Internal carotid artery endarterectomy--prospective evaluation]. / Endarterektomia tetnicy szyjnej wewnetrznej--ocena prospektywna.

The aim of this study was to present early and late results of carotid endarterectomy (CEA). We evaluated prospectively 270 CEA performed from 1990 to 1996. More of our patients were men (62%), their age ranged from 28 to 82 years (mean 62.4). Preoperative high grade stenosis (> 70%) of internal carotid artery stenosis was recognized in over 91% of patients according to duplex examination. All operations were performed by the same surgical team with the use of standard CEA without patching. General anaesthesia was used to the middle of 1993. Then all the patients were operated on under regional anaesthesia. Our follow-up consisted of clinical and duplex-scan examination performed regularly from 3 to 72 months after CEA. In the immediate postoperative period (30 days) four patients died (mortality rate 1.5%), mostly due to MI. The long term (72 months) follow-up revealed 12 deaths mostly due to heart attacks or cancer. We observed 11 high grade (> 70%) late recurrent stenoses. There were no deaths due to stroke from the operated artery. Duplex-scan of carotid arteries is a very effective and safe method of preoperative and postoperative evaluation. Regional anaesthesia allows direct estimation of neurological statement during operation. CEA is the only one method of stroke prevention in patients with symptomatic high-grade stenoses.

[Transcutaneous balloon angioplasty in the treatment of subclavian steal syndrome. Characteristics of vertebral basal flow with transcranial Doppler technique]. / Przezskórna angioplastyka balonowa w leczeniu zespolu podkradania tetnicy podobojczykowej. Charakterystyka parametrów przeplywu krwi w krazeniu podstawno-kregowym technika transcranial Doppler.

Subclavian steal syndrome (SSS) appears when the origin of the subclavian artery (SA) is occluded or stenosed. Introduction of transcranial Doppler sonography (TCD) provided an opportunity to evaluate parameters of the blood flow in the vertebral (VA) and basilar artery (BA). Measurements of blood flow velocities performed at rest and after the brachial hyperemia test allow one to classify hemodynamic types of SSS. The aim of the study was to categorize types of steal and to compare the differences of flow patterns before and after percutaneous transluminal SA balloon angioplasty (SA-PTA). Fourty-eight patients with angiographically confirmed SSS (aged from 27 to 68 years, mean 53; 2/1 f/m ratio) were examined with 2 MHz range-gated, pulsed transcranial Doppler device (TC 2-64B EME). Both VA and BA were evaluated by the transoccipital approach at rest and during the brachial hyperemia. In 5 cases (10.4%) permanent reversal blood flow in the BA was observed (complete basilar steal). In flow in the BA blood flow was in the normal direction at rest and altered (reversed or decreased) when induced with brachial hyperemia test (transient basilar steal). In the next 14 patients (29.2%) permanently reversed VA blood flow was observed with only a slight or no alterations of the BA flow after the hyperemia test (complete vertebral steal). In the last 19 cases (39.6%) alterations of the VA blood flow without changes in BA flow were observed (latent vertebral steal). Between 1991 and 1994 twenty seven symptomatic patients with different hemodynamic types of SSS were treated with SA-PTA. TCD evaluation of VA's and BA using the hyperemia test was performed before, 3 to 7 days and 3 months after morphologically and hemodynamically successful subclavian artery balloon PTA. Normal results of vertebrobasilar examinations were obtained in 26 cases after this procedure. In one case the latent vertebral steal was detected. The 28 months mean follow-up revealed no significant changes in TCD flow patterns recorded from VA's and BA. After collecting data of about 60 patients with SSS we examined with TCD we conclude that: in patients with a hemodynamically significant SA stenosis the presence of reversed ipsilateral VA blood flow (a radiologic steal) its not a good determinant of either the presence or type of presenting symptoms and after successful PTA or recanalisation and PTA of SA in almost all cases we examined close to normal TCD recordings in BA and VA.

The effect of internal carotid artery elongation on intracranial blood flow.

Redundant length of the cervical part of the internal carotid artery (ICA) is a clear angiographic entity although the clinical significance is uncertain. Transcranial Doppler sonography (TCD) examinations were performed on 15 patients with 23 elongated ICAs. The recordings were obtained with the use of flat 2 MHz probe from the middle cerebral artery (MCA) and the intracranial part of ICA at rest and in eight possible extreme positions of head and neck rotation. The mean blood flow velocity in the intracranial part of the ICA obtained in the neutral position was 50.1 +/- 8.3 cm s-1 and after head and neck rotations was 49.8 +/- 9.5 cm s-1. The mean blood flow velocity in the MCA was 55.8 +/- 6.7 cm s-1 and did not change significantly after head and neck movements (54.9 +/- 7.6 cm s-1). Analysis of 368 one minute recordings from all possible head positions showed no significant changes of blood flow velocity. Rotation of the head and neck has no significant influence on intracranial blood flow velocity in the presence of carotid artery elongation.

Collateral role of the external carotid artery and its branches in occlusion of the internal carotid artery.

In 40 patients with unilateral occlusion of the internal carotid artery, using a transcranial Doppler device, blood flow velocity in the ipsilateral ophthalmic and middle cerebral artery was registered. During compression of the ipsilateral common carotid artery a decrease of ophthalmic artery flow velocity was noted in 39 patients (97.5%) and a decrease of middle cerebral artery flow velocity in 8 patients (20%). The average decrease of mean velocity in the middle cerebral artery was 4.5% of the initial value. During compression of the ipsilateral superficial temporal and facial arteries ophthalmic artery flow velocity decreased in 10 patients (25%) and no marked decrease of middle cerebral blood flow was noted. Conclusions. The external carotid artery in most of the patients with internal carotid occlusion is of no significance for cerebral blood supply, but it is the most important source of collateral blood supply to the eye. The maxillary artery, and not superficial temporal and facial as it seemed in periorbital Doppler examinations, is the branch of the greatest collateral value for the eye and brain.

Surgical management of abdominal aortic aneurysms in Poland. A multi-centre study.

Abdominal aortic aneurysm resections were performed on 941 patients between 1987 and 1991 in nine selected university vascular units in Poland. The aim of the study was (1) to determine how grave the problem of abdominal aortic aneurysms is in the main vascular centres in our country, (2) to evaluate the methods of management, (3) to trace the most common postoperative complications, and (4) to estimate results. Hospital mortality rate for 730 elective and urgent resections was 8.2%. The emergency resection mortality rate for ruptured aneurysm was 60.2%. The most common postoperative general complications were: cardiac (178-18.9%), pulmonary (76-8.1%), renal failure (58-6.2%) and cerebrovascular accidents (23-2.4%). The postoperative local complications (113) occurred in 87 (9.2%) patients. The most common were: colon ischemia (22-3.5%), haemorrhage (30-3.2%), acute graft occlusion (22-2.3) and peripheral embolism (19-2%). Sixty-five patients required early reoperation undergoing a total of 74 additional operative procedures. The local complications occurring in analysed material significantly influenced the results. Mortality in reoperated patients was almost twice as high as among those not reoperated (p < 0.01). Analysis of the material revealed no differences in the obtained results of aneurysm surgery in the succeeding years of our study, when expecting improvement in the last years. The cause of this could be treatment of more high risk patients. The absolute number of patients with abdominal aortic aneurysms referred to the unit influenced results.(ABSTRACT TRUNCATED AT 250 WORDS)

Prediction of stature from hand measurements.

A sample of 166 normal adult males and females was taken from different colleges of Assiut representing those living in upper Egypt. Each subject has been studied for measurements of stature (S), hand length (HL) and hand breadth (HB). The data were statistically analysed in order to assess the relationship between stature and hand measurements. The correlation matrix of the study indicates close similarity of the relationship between stature and hand measurements in both sexes and in both sides. A generalized multiple regression equation has been designed to estimate stature from values of hand length and hand breadth regardless of sex or side in the form: S = 34.5 + 5.77 HL + 2.7 HB +/- 5.1. This equation may be helpful to obtain approximate stature when there is difficulty in obtaining a direct measurement or where there is a chance print of a criminal or an amputated hand or arm.