Important Collateral Vessels Research Articles

The Use of Re-entry Devices in Aortoiliac Occlusive Disease.

Endovascular approach is the first-choice treatment in patients suffering from aortoiliac occlusions. Nevertheless, standard endoluminal revascularization fails in treating occlusions in about 20% (1) of cases. Thus, subintimal revascularization can be a solution, but it fails in 25% (2) of cases as well. In the last decades, different devices have been created, in order to ease the cross back into the true lumen, when standard subintimal revascularization does not work or risks to occlude important collateral vessels. Herein, we revise the currently available re-entry devices and their application in the aortoiliac occlusive pathology.

Pathogenesis of Portal Hypertension and Esophageal Varices

Esophageal varices are the major complication of portal hypertension. It is detected in about 50% of cirrhosis patients. Portal hypertensionis associated with both increased portal inflow and increased intrahepatic vascular resistance. Intrahepatic vascular resistance is caused by the architectural distortion of the liver resulting from fibrosis and by increased sinusoidal tone. Portal venous inflow results from a combination of ahyperdynamic circulatory state and increased plasma volume. In response to the increased portal pressure, collateral circulation develops by the opening of preexisting vascular channels. Esophagogastric varices are the most important collateral vessels: they tend to increase in size with the increase of portal pressure and rupture when wall tension exceeds a critical value.

Elective sac perfusion to reduce the risk of neurologic events following endovascular repair of thoracoabdominal aneurysms

Spinal cord ischemia (SCI) is a catastrophic complication of thoracoabdominal aortic aneurysm (TAAA) repair. This article describes our early experience with a technique for maintaining perfusion of segmental vessels (intercostals and lumbars) in the early postoperative period after endovascular repair of a TAAA, with "sac perfusion branches" added to custom-made stent grafts. These are closed 7 to 10 days after the first procedure to complete exclusion of the aneurysm. We have used this technique in 10 patients with type II TAAAs. One developed monoparesis of the right leg during a period of hypotension secondary to a cardiac event and died within 30 days. Two patients developed lower limb weakness after closure of the perfusion branches, both with full recovery. Controlled perfusion of segmental vessels with perfusion branches is feasible and may be a useful adjunct to prevent SCI, providing protection to spinal cord perfusion during the immediate postoperative period when risk of SCI is greatest.

Kawasaki Disease

Kawasaki disease (KD) is an acute systemic inflammatory illness that occurs predominately in children <5 years of age. The reported incidence varies widely depending on the ethnicity of the population and the method of case ascertainment. Recent reports would suggest the annual incidence is ≈20 to 25 per 100 000 children <5 years of age in North America, with the highest reported incidence of 188 being in Japan, where the disease was first described in 1967.1 The illness is self-limited and of unknown cause, but is complicated by a systemic vasculitis with a predilection for small- to medium-sized arteries, particularly the coronary arteries. The majority of patients will have either transient coronary artery dilation or no coronary artery luminal changes as noted on echocardiography. Long-term prognosis for these patients is considered to be excellent. Coronary artery aneurysms occur in 25% of patients, but the prevalence is reduced to ≈4% for patients treated with intravenous immunoglobulin infusion within 10 days of illness onset. Aneurysms are associated with an intense inflammatory cell infiltrate, destruction of the internal elastic lamina, and smooth muscle cell death. Coronary artery involvement is usually maximal within 6 to 8 weeks after the acute episode. Regression of aneurysms can occur primarily through myointimal proliferation, although the arterial structure and function remains abnormal,2 and there is an important ongoing risk of stenoses and occlusions.3 Long-term cardiology assessment and management is required, and some of these patients may require revascularization procedures or, rarely, cardiac transplantation. KD has become the most prevalent acquired cardiac disease in children in developed countries. Article see p 60 Although coronary artery complications are the predominant cause of morbidity and mortality, other cardiovascular abnormalities can occur. Valvulitis is a less prevalent complication, and there have been case reports of important long-term aortic and …

Balloon Occlusion of the Celiac Artery: A Test for Evaluation of Collateral Circulation Prior Endovascular Coverage

Introduction Visceral ischemia is a possible complication after endovascular coverage of the celiac artery (CA). A selective mesenteric angiography during simultaneous balloon occlusion of the CA imitates endovascular coverage and might therefore be suited for evaluation of collateral circulation. We report the feasibility of a balloon occlusion test (BOT) of the CA for this purpose. Report We performed a BOT in 5 patients selected for endovascular surgery with intended coverage of the CA. The BOT could demonstrate sufficient collateral circulation in all cases, which was not evident without occlusion of the CA. The most important collateral vessels were the pancreaticoduodenal arcades and the dorsal pancreatic artery. All patients tolerated the BOT well without abdominal symptoms or pathological laboratory findings. Discussion Our report suggests that a BOT of the CA is a feasible and safe procedure. It can demonstrate collateral pathways before definite coverage is performed. This test might be useful for selection of patients prior intended coverage of the CA.

Pyloromyotomy: technique and use for gastric drainage combined with vagotomy.

Abstract Gastric drainage must accompany vagotomy and for this purpose gastro-enterostomy and pyloroplasty are equally effective. When the stomach requires to be extensively mobilized, as for high oesophagogastric anastomoses, these drainage operations interfere with important collateral vessels and they may impede mobilization of the stomach by shortening or anchoring the gastric outlet. In this situation both internal pyloric stretching and stretch pyloromyotomy have, over a period of 10 years, provided effective gastric drainage. Internal pyloric stretching without myotomy would seem to be the ideal decompressive manoeuvre for cases of high gastrooesophagectomy. Pyloric stretching with or without myotomy has been used in 56 cases of transthoracic hiatus hernia repair accompanied by vagotomy for associated duodenal ulcers. The technique was used originally only because it was simpler than a pyloroplasty to perform through a left thoracotomy. On the basis of postoperative symptoms, gastric emptying times, and fasting gastric secretion volumes, it has proved as effective as other drainage procedures provided duodenal or pyloric fibrosis is absent or minimal. The technique permits of accurate hernia repair with vagotomy through a standard left thoracotomy.

Temporal patterns of gene expression after acute hindlimb ischemia in mice: insights into the genomic program for collateral vessel development

ObjectivesWe sought to understand the genomic program leading to collateral vessel formation. BackgroundRecently, technology has advanced to the point that it is now possible to elucidate the large array of genes that must be expressed, as well as the temporal expression pattern, for the development of functionally important collateral vessels. In this investigation, we used deoxyribonucleic acid array expression profiling to determine the time course of differential expression of 12,000 genes after femoral artery ligation in C57BL/6 mice. MethodsRibonucleic acid was extracted from the adductor muscle, which showed no signs of ischemia. Sampling was at baseline, 6 h, and 1, 3, 7, and 14 days after femoral artery ligation or sham operation. ResultsFemoral artery ligation caused the differential expression (>2-fold) of 783 genes at one or multiple time points: 518 were induced and 265 were repressed. Cluster analysis generated four temporal patterns: 1) early upregulated (6 to 24 h)—immediate early transcriptional factors, angiogenesis, inflammation, and stress-related genes; 2) mid-phase upregulated (day 3)—cell cycle and cytoskeletal and inflammatory genes; 3) late upregulated (days 7 to 14)—angiostatic, anti-inflammatory, and extracellular matrix-associated genes; and 4) downregulated—genes involved in energy metabolism, water channel, and muscle contraction. Microarray data were validated using quantitative reverse transcription polymerase chain reaction. ConclusionsThis study documents the large number of genes whose differential expression and temporal functional clustering appear to contribute to collateral formation. These results can serve as a genomic model for arteriogenesis and as a database for developing new therapeutic strategies.

Central nervous system alterations in liver cirrhosis: the role of portal-systemic shunt and portal hypoperfusion.

The role of portal-systemic shunting and portal liver hypoperfusion in the pathophysiology of central nervous system dysfunction (CNSD) of cirrhosis is not yet well defined. It is well known that one of the most important collateral vessels (CVs) is a patent paraumbilical vein (PUV), but there is controversy regarding its clinical significance. We have evaluated the relationships between neuropsychological and EEG alterations, ammonia plasma level (NH4), hepatic function, and portal hemodynamics (Doppler Ultrasound) in 95 cirrhotic patients. Patency, diameter, or flow of PUV or the presence of other CVs were not related to an increased prevalence of neuropsychological or EEG abnormalities. Patients with effective portal flow (EPF = portal flow - PUV flow) lower than 692 mL/min (median) had a significantly higher risk of failing the neuropsychological test, or of having an altered EEG. Low EPF and prothrombin time (<50%), and high NH4 (51 micromol/L) were independent predictors of an abnormal EEG. Considering both low EPF and the numerosity of CVs, only low EPF was found to explain EEG alterations. In conclusion, portal liver hypoperfusion and decreased liver function were associated with an increased risk of CNSD in cirrhotic patients, whereas PUV patency per se was not.

Central nervous system alterations in liver cirrhosis: the role of portal-systemic shunt and portal hypoperfusion.

The role of portal-systemic shunting and portal liver hypoperfusion in the pathophysiology of central nervous system dysfunction of cirrhosis is not yet well defined. It is well known that one of the most important collateral vessels (CV) is a patent paraumbilical vein (PUV) but there is controversy regarding its clinical significance. We have evaluated the relationships between neuropsychological and EEG alterations, ammonia plasma level (NH4), hepatic function, and portal hemodynamics (Doppler Ultrasound) in 95 cirrhotic patients. Patency, diameter, or flow of PUV or the presence of other CV were not related to an increased prevalence of neuropsychological or EEG abnormalities. Patients with effective portal flow (EPF = portal flow - PUV flow) lower than 692 mL/min (median) had a significantly higher risk of failing the neuropsychological test, or of having an altered EEG. Low EPF and prothrombin time (<50%), and high NH4 (> or = 51 micromol/L) were independent predictors of an abnormal EEG. Considering both low EPF and the numerosity of CV, only low EPF was found to explain EEG alterations. In conclusion, portal liver hypoperfusion and decreased liver function were associated with an increased risk of central nervous system dysfunction in cirrhotic patients, whereas PUV patency per se was not.

Timed bilateral iliofemoropopliteal arteriography. A simple apparatus and a technique.

Currently available reconstructive vascular surgical techniques have made complete and detailed mapping of the major vessels of the lower extremities of fundamental importance. Experience in this field has shown that the velocity of blood flow in extremities is often quite unpredictable. Thus, if one wishes to visualize the arterial tree from the aortic bifurcation to the popliteal trifurcation, along with important collateral vessels in both lower extremities simultaneously and completely, serial exposures of long cassettes are essential. While this principle has been accepted by many observers, and various modifications of the technique have been practiced in many large centers, 1-16 it is not yet generally used in the average hospital for femoral arteriography, possibly because of the complexity or expense of most serial long-casette changers. Accordingly, many surgeons have been content with incomplete studies and substandard arteriograms, to avoid multiple injections or repeated examinations in patients in whom the velocity