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In rare cases the usage of the internal thoracic vessels as recipient vessels in reconstructive surgery of the head and neck region with free tissue transfer is a challenging but valid alternative if local recipient vessels are unusable.
The prognostic implications of coronary collateral channels were examined in 359 medically treated patients with one vessel coronary artery disease and a normal left ventricular ejection fraction (greater than or equal to 50%). There were 149 patients with isolated left anterior descending coronary artery disease (group I) and 210 patients with isolated left circumflex or right coronary artery disease (group II). Collateral channels were present in 68 patients (46%) in group I and 115 patients (55%) in group II. During a follow-up period of up to 82 months (mean +/- SD 34 +/- 18), there were 23 cardiac events (4 patients died of cardiac causes and 19 patients had a nonfatal acute myocardial infarction). Actuarial survival analysis showed that the risk of cardiac events was not related to the presence of collateral channels in the two groups. Thus, the risk of cardiac events is not related to the presence or absence of collateral channels in patients with one vessel coronary artery disease. Further, the risks of cardiac death (0.3%/yr) and nonfatal myocardial infarction (1.9%/yr) are very low in medically treated patients with one vessel coronary artery disease and a normal left ventricular ejection fraction.
The aim of this interdisciplinary study was to evaluate power Doppler imaging as a method of collecting reliable preoperative data concerning the diameters and topography of exemplary internal mammary vessels as recipient vessels in reconstructive microsurgery. Thirteen female patients (range, 37 to 58 years; mean, 45.6 years) were examined preoperatively with power Doppler imaging from the first to the fifth intercostal space parasternally and bilaterally. These data are compared with measurements obtained intraoperatively in each individual. Mean velocity in the artery in the second intercostal space on the right side is 47.11 cm/sec (range, 15 to 90 cm/sec) and on the left side is 42.25 cm/sec (range, 18 to 95 cm/sec). Mean velocity in the vein in the second intercostal space on the right side is 17.80 cm/sec (range, 10 to 30 cm/sec) and on the left side is 13.06 cm/sec (range, 5.3 to 32 cm/sec). The topographic results are in close agreement with intraoperative measurements and previous anatomical studies. Sonographic preoperative data of arteries (mean, 1.88 mm) show slightly smaller diameters than intraoperative measurements (mean, 2.08 mm), whereas veins show slightly larger diameters in sonography (mean, 2.33 mm) than intraoperatively (mean, 2.12 mm). Mean sonographic diameter of artery ranges from 2.14 mm (second intercostal space) to 1.46 mm (fifth intercostal space), of the vein from 2.76 (second intercostal space) to 1.25 mm (fifth intercostal space). In one case, a vein was not detectable. This noninvasive method leads to confirmation of the preoperative choice of the optimal recipient vessels for free tissue transfer and does not harm the patient.
Acute hypertensive damage to small arteries and arterioles in rats was induced by intravenous injections of Hypertensin. The in vitro immunological method of the agarose migration technique was used to demonstrate delayed-type autoimmunity against arterial vessel-wall antigens. By this technique the autoimmunity could be demonstrated for about 16 weeks after the acute hypertensive damage to the arterial vessels. The results of the autoimmunity were given as migration indices. These were lowest during the first 4-5 weeks after the damage to the vessels whereupon they showed higher and higher values, and finally the migration indices were identical with those of the control rats after about 16 weeks.
Vessels from normal pigs and pigs with severe von Willebrand disease were exposed for up to 30 minutes to both nonanticoagulated and heparinized blood from normal pigs in an ex vivo perfusion system. Shear rates at the vessel surface were varied over a broad physiological range, gamma w = 212 to 3380 sec-1. The deposition of 111In-labeled platelets was determined by radiometric counting. For all shear rates and exposure times investigated, the levels of platelet deposition on de-endothelialized thoracic aorta of normal and von Willebrand disease pigs were not significantly different. Thus, the functional activity of the vessels correlated with the results obtained previously by immunofluorescence. Namely, the von Willebrand factor protein in the thoracic subendothelium of normal pigs is significantly diminished or absent and is comparable to the levels observed in von Willebrand disease pigs.
Endothelial dysfunction is considered a key early event in atherosclerosis. Using a novel ultrasound method, brachial artery endothelial and smooth muscle physiology were studied in 20 adolescents with IDDM and compared to that in 20 nondiabetic subjects matched for age (13-22 years), gender and vessel size. Endothelium-dependent dilatation (EDD) was assessed in response to flow (EDD) and endothelium-independent vasodilatation after sublingual glyceryl trinitrate (GTN). Both EDD and GTN were reduced in those with IDDM compared with controls: 5% vs 9%, (p = 0.0002) and 14% vs 21% (p = 0.002). Abnormal EDD was found in 12 IDDM adolescents (diabetes duration 3.3-14.9 years). The maximum albumin excretion rate of the diabetic group was 17 micrograms/min. Four adolescents had retinopathy assessed by stereoscopic fundus photography. Three had at least one of four cardiovascular autonomic test abnormalities. There was no significant correlation observed between the test for early large vessel disease and those for diabetic microangiopathy. Large vessel dysfunction was the most common abnormality.
Acute vessel closure complicates 0.5 9.3% of percutaneous coronary interventional procedures. This case series demonstrates the potential value of distal vessel angiographic visualization during abrupt vessel closure, which allows rapid determination of the underlying mechanism and the subsequent appropriate therapy.
Two types of anastomotic new vessels develop after retinal branch vein occlusions. In a previous article (Arch. Ophtal. (Paris), 1977, 8-9, pp. 507-522) the useful collateral vessels were described in the re-establishment of a better circulation in the territory of the occluded vein. The second part discusses new vessels: they are dangerous and useless. Their pathogenesis poses the problem of the relationship between hypoxia, ischaemia, revascularisation and vasoproliferation. Their prevention and treatment calls for laser photocoagulation of the ischaemic territory.
This study was performed to define the conditions present in chronic total occlusion of all three coronary vessels. Each left descending coronary artery (LAD), left circumflex branch (LCX) and right coronary artery (RCA) was totally occluded angiographically in 5 patients (mean age 64, male 3, female 2). Four of them had history of myocardial infarction. Anginal type was effort angina in all patients, and two cases showed unstable angina. Good collateral supply was found in the distal portions of occluded vessels from proximally located branches, such as Conus branch, Right ventricular branch, Septal branch and Left atrial circumflex branch. Almost all of the occlusions were located at mid portions (13/15: mid, 2/15: proximal). Ejection fractions (EF%) of the 5 patients were 70%, 69%, 60%, 28% and 22% respectively. EF was correlated with the degree of collateral supply and one of them (22%) ended in sudden death. These findings suggest that the mid portion occlusion, good collateral supply and a long history of angina pectoris are important factors involved in chronic total occlusion of the three coronary vessels.
We examined our practice of invasive therapy for one- and two-vessel coronary disease to assess the impact of the randomized trials of coronary surgery and the current use of angioplasty. We first reviewed our results with coronary artery bypass graft in equivalent patients in the Coronary Artery Surgery Study with one- and two-vessel disease between 1976 and 1981. Among 1376 patients, hospital mortality was 0.07%, and 5-year survival was 95.2% +/- 0.8%. To define trends in invasive therapy, which have since occurred, we compared 100 patients with one- and two-vessel disease in each of three groups: 1979 coronary artery bypass graft, 1984 coronary artery bypass graft, and 1984 percutaneous transluminal coronary angioplasty. Preoperative characteristics in the average 1979 and 1984 patients were similar; however, in 1984, patients who had a coronary artery bypass graft were older than patients who had percutaneous transluminal coronary angioplasty (61.5 versus 56.7 years, p less than 0.01), they required more heart medications (2.1 versus 1.5, p less than 0.01), had more previous infarctions (0.8 versus 0.5, p less than 0.01), and more patients had an ejection fraction of less than 50% (34% versus 7%, p less than 0.01). Patients who had angioplasty had a shorter postoperative stay (median number of days 7, 7, 2, p less than 0.01). Freedom from major complications was similar among the groups (91%, 87%, 85%). Unstable symptoms were the most frequent indication for invasive therapy (approximately 80%), whereas long-term symptoms, those considered in the randomized trials, occurred in relatively few patients. The number of patients without at least one definite indication for invasive therapy was 13%, 3%, and 11%, p less than 0.05, suggesting that the indications for the 1984 coronary artery bypass graft group have become more restrictive since the 1979 coronary artery bypass graft group. Indications for the 1984 percutaneous transluminal coronary angioplasty group remained less restrictive, being similar to those for the 1979 coronary artery bypass graft group. A continuing trend toward the use of percutaneous transluminal coronary angioplasty was evident, as 56% of the 1979 coronary artery bypass graft group of patients and 32% of the 1984 coronary bypass group of patients would be offered percutaneous transluminal coronary angioplasty rather than coronary artery bypass graft on the basis of 1986 percutaneous transluminal coronary angioplasty criteria. The p values were obtained with analysis of variance or chi 2 test.
Only few studies deal with the problem of an isolated stenosis of the left anterior descending coronary artery (LAD) leading to a combined anterior and inferior myocardial infarction in the ECG and VCG. In the present study patients with electrocardiographic signs of anterior and inferior myocardial infarction and either one-vessel disease of the LAD branch (n = 27; group I) or two-vessel disease including the LAD and the right coronary artery (RCA) (n = 29; group II) were investigated. Due to the anterior myocardial infarction present in all patients, unequivocal signs of posterior and posterolateral infarct location were missing in the ECG and VCG. There was a distinct variability with regard to Q-wave duration and amplitude in the inferior leads of the ECG and of the Q/R-relation in the scalar lead Y of the VCG (Frank-leads) in patients with isolated LAD disease when compared to those with combined LAD and RCA disease, but no reliable parameter was found in the ECG and VCG which allowed to allocate patients to one of the two groups. On the other hand, there were significant differences in hemodynamics and left ventricular function between the two groups. Group I patients showed a significantly higher left ventricular ejection fraction (mean 49 +/- 15%) than patients with two-vessel disease (group II) (mean 42 +/- 12%) (p less than 0.05). Left ventricular end-diastolic pressures at rest (13 +/- 7 mm Hg).(ABSTRACT TRUNCATED AT 250 WORDS)
During infragenicular bypass, internal occlusion of the distal vessel avoids unnecessary dissection and potentially damaging use of external clamps or vessel loops while improving exposure and patency. This technique is especially useful in patients with small or calcific vessels in whom distal reconstruction is necessary for limb salvage.
On x-ray films of 51 children with asthma bronchiale the authors determined the vascular diameter of the right ascending pulmonary artery, the right vein of the upper lobe, and the peripheral vessels in the upper and lower pulmonary fields at an exactly defined distance from the hilus point, and compared these data with those of a control group of 143 healthy children. During the asthma attack the width of the right descending pulmonary artery and of the vein of the upper lobe corresponded to the values of the control group, whereas the vascular diameters in the upper and lower fields were clearly narrowed. Moreover, in most of the asthmatic children the authors found arc-shaped vessels and irregularly occluded vessels in the periphery of the lungs.
A report is given on the study of cerebrovascular systems in experimental animals and corpses and the demonstration of cerebral tumours be means of models of vascular system. After a survey of the development of model representation, the technique of the vessel injection, the various injection materials and methods of preparation are described in detail. Advantages and disadvantages of the individual methods and certain peculiarities in model representations of transplantation tumours and various human brain tumours are presented. Besides, a multitude of pictures which document the results of the experiments, general laws of the tumour development, angioarchitectufe of the cerebral tumours and the changes in pre-existing and newly formed vessels in and around the tumour are briefly dealth with. The individual results of systematic investigations into the vascular system of cerebral tumours--of human brain vessel models, of transplantation tumours and special angioarchitecture of gliomatous brain tumours--will be published in individual articles appearing later.
In the total abdominal island skin flap of the rat based on both epigastric vessels in the groin, postoperative development after arterial or venous or complete division of the neurovascular bundle was documented. Photographic documentation, planimetry of the surviving skin area were used as methods together with evaluation of the blood supply of the flaps by Xe-133 clearance. The resulting new architecture of vessels was shown photomacroscopically by Indian ink injection. The function of arterial inflow and venous outflow was shown by microangiographical fluorescent methods. Hence, it was possible to combine special operation methods with definite new vessel structures, typical necrotic areas and postoperative mean value clearance results. Due to the difference of the xenon clearance results in individual cases, this method proved incapable of giving a safe prognosis on the survival of the special flap. Fluorescent microangiography pointed to the type of surgery which had been selected, and allowed functional evaluation of the blood supply of the flap.
Previous studies showed that extracellular matrix protein, fibulin-2, is expressed during epithelial-mesenchymal transformation in the endocardial cushion matrix during embryonic heart development. Our current study revealed that, in addition to the cardiac valvuloseptal formation, fibulin-2 is synthesized by the smooth muscle precursor cells of developing aortic arch vessels and the coronary endothelial cells that are originated from neural crest cells and epicardial cells, respectively. In the cardiac valves and the aortic arch vessels, fibulin-2 expression shows robust up-regulation when the transformed mesenchymal cells migrate into the existing extracellular matrix. In the epicardium, epicardial cells produce fibulin-2 upon their migration over the myocardial surface and its expression persists throughout coronary vasculogenesis and angiogenesis. Fibulin-2 is produced by the endothelial cells of coronary arteries and veins but not by the capillary endothelial cells in the myocardium. Thus, fibulin-2 not only uniquely marks the transformed mesenchymal cells during mouse embryonic cardiovascular development, but also indicates vascular endothelial cells of coronary arteries and veins in postnatal life.
PURPOSE: Chick choroidal lymphatics swell rapidly during recovery from form-deprivation occlusion, leading to the question of functional significance. To date, analysis of lymph in initial lymphatics has been problematic because of the difficulties of access. However, elemental composition can be determined using scanning electron microscope (SEM) X-ray microanalysis. This study investigated whether cryo-fixation would permit vascular fluids to be analysed in situ. METHODS: Two chicks were raised normally and seven were raised with monocular occlusion for 12 days before varying periods of normal visual experience. The eyes were rapidly frozen, fractured and X-ray spectra obtained from the lumina of lymphatic and blood vessels in a Cambridge S360 SEM. RESULTS: The elemental signatures of Na/Cl/K/P/S distinguished the two vessel types. CONCLUSIONS: These results suggest this bulk-frozen tissue technique can quantify relative changes in elemental species present in various ocular compartments in response to light-induced changes in the retina.
The rat tail vascularization is histologically re-examined especially with respect to blood sampling and vascular-injection methods. The terminal third of the tail is recommended for blood vessel puncturing. In this segment, the arteries and veins are most prominent, since the structures of the musculo-skeletal system diminish towards the tip of the tail. In addition to the commonly-known blood vessels (one ventral artery, two lateral veins), there is a dorsal vein in the rat tail that is well suited for puncture and cannulation.