Venous Arterialization Research Articles

Indirect carotid-cavernous fistula of low-flow type: Color Doppler Imaging of retrobulbar vessels findings

Background. Carotid-cavernous fistulas (CCF) of low-flow type are the results of development of communication between small arteries and veins of cavernous sinus. Aim. To assess the role of CDI of retrobulbar vessels in the study of two patients with CCF of low-flow type. Methods. We have used a sonographer with 9MHz linear probe. Results. The initial diagnosis was suspected clinically: both patients presented unilateral chemosis and orbital bruit. It was sustained by CDI of retrobulbar vessels: reversed flow in the superior ophthalmic vein, with a venous arterialisation and confirmed with complete selective digital subtraction angiography, which is essential for a correct diagnosis( early opacification of veins draining cavernous sinus, etc). Conclusions. CDI of retrobulbar vessels is a repetitive non-invasive technique, which is used for monitoring carotid-cavernous fistulas of low-flow type, because they are sometimes a self-limiting pathology (spontaneous venous thrombosis).

Deep calf veins arterialization for inferior limb preservation in diabetic patients with extended ischaemic wounds, unfit for direct arterial reconstruction: preliminary results according to an angiosome model of perfusion

The study proposes to evaluate the limb salvage in diabetic ischemic limbs with foot wounds, where all types of common arterial reconstructions have previously failed or were impracticable, by using the "SAVES" technique (selective arterio-venous endoluminal switch) for deep calf veins arterialization upon an angiosomes model of distribution. Since January 2001 until September 2009, a series of 26 limbs with threatening ischemic wounds in 25 diabetic patients at high risk for major amputation and no feasible conventional revascularizations, were treated by the hybrid (surgical and endovascular) SAVES technique and were retrospectively reviewed. The method consists in selective arterialization of the deep calf veins with synchronous endoluminal exclusion of the collaterals, guided by an angiosomes- model of vascularization. There were 12 limbs treated by preferential anterior tibial veins arterialization, 11 with revascularizations in the posterior tibial and three others targeting the peroneal-related territorial wound distribution. The initial technical success was achieved in 21 of 26 limbs (80%) with 0% 30-day perioperative mortality rate. The cumulative primary and secondary patency were: 66%, 60% and 48%, at 12, 24 and 36 months, respectively. Limb salvage revealed 73% at one year and steady 73% afterwards, while the clinical success was: 68%, 60% and 60% at identical time intervals. Selective deep calf venous arterialization oriented by an angiosome model for reperfusion may represent a complementary alternative for limb salvage in extreme situations, inoperable by direct arterial methods. Larger groups of study are needed to ascertain these preliminary observations.

Utilização da safena magna in situ para arterialização do arco venoso do pé

CONTEXTO: O tratamento da isquemia crítica de membros inferiores sem leito arterial distal pode ser realizado por meio da inversão do fluxo no arco venoso do pé. OBJETIVO: O objetivo deste trabalho foi apresentar a técnica e os resultados obtidos com a arterialização do arco venoso do pé, mantendo a safena magna in situ. MÉTODOS: Dezoito pacientes, dos quais 11 com aterosclerose (AO), 6 com tromboangeíte obliterante (TO) e 1 com trombose de aneurisma de artéria poplítea (TA) foram submetidos ao método. A safena magna in situ foi anastomosada à melhor artéria doadora. O fluxo arterial derivado para o sistema venoso progride por meio da veia cujas válvulas são destruídas. As colaterais da veia safena magna são ligadas desde a anastomose até o maléolo medial, a partir do qual são preservadas. RESULTADOS: Dos pacientes, 10 (55,6%) mantiveram suas extremidades, 5 com AO e 5 com TO; 7 (38,9%) foram amputados, 5 com AO, 1 com TO e 1 com Ta; houve 1 óbito (5,5%). CONCLUSÃO: A inversão do fluxo arterial no sistema venoso do pé deve ser considerada para salvamento de extremidade com isquemia crítica sem leito arterial distal.

Salvage of the skin envelope in complex incomplete avulsion injury of thumb with venous arterializaiton: A case report

Treatment of an avulsion or degloving injury of the hand is a difficult but not unusual operation for plastic reconstructive or hand surgeons. The avulsion may be salvaged by arteriovenous shunting technique. We present a patient with incomplete avulsion injury of the distal phalanx of thumb. Arteriovenous shunting was created and the wound reconstructed primarily under venous arterialization. The avulsed skin envelope was survived well and functional status was improved.

Successful Repair for a Ruptured Venous Aneurysm: An Unusual Complication of Venous Arterialization in Buerger's Disease

We report a ruptured venous aneurysm, an unusual complication of venous arterialization for lower limb ischemia in Buerger's disease. Arteriovenous shunt ligation and aneurysm resection were performed successfully, with the distal limb perfusion preserved. By our very limited experience, venous arterialization may be ineffective on improving lower limb ischemia with Buerger's disease.

Combined Distal Venous Arterialization and Free Flap for Patients with Extensive Tissue Loss

We evaluated the mid-term outcome of distal venous arterialization (DVA) and the role of a combined free flap as a bridgehead for blood supply. In the past 5 years, nine patients with extensive tissue loss and lacking graftable distal arteries underwent DVA. These consisted of four primary DVAs, three combined DVA and free flap procedures, and two adjuvant DVAs for hemodynamically failed distal bypasses. After nine primary DVAs, three redo DVAs were performed for early failure. Etiologies were four Buerger disease and five arteriosclerosis obliterans, including three dialysis patients. Among the nine DVA cases, there were five primary failures: two underwent amputation, two had successful redo DVA, and the remaining one did not require redo DVA. Primary patency, secondary patency, and limb salvage rates were 44.4%, 55.6%, and 77.8%, respectively. The postoperative period was 1-36 months (median 12). Angiography demonstrated DVA was effective in the early period, and development of collaterals or a capillary network from the free flap replaced the DVA function in the intermediate period. DVA can be effective as a procedure for limb salvage in patients without graftable distal arteries, and a combined free flap is effective and functions as a bridgehead for blood supply to the ischemic zone.

Foot venous system arterialization for salvage of nonreconstructable acute ischemic limb: A case report

Patients 73 years old man, was admitted to the Hospital with acute ischaemia of the left lower limb, pain started 4 days ago. Ultrasound investigation and lower limbs angiography were performed. Giant infrapopliteal aneurysm and thrombosis due to massive embolism of the crural and pedal arteries' was revealed. In order to keep the limb, urgent surgical treatment--popliteal aneurysm ligation and foot venous system arterialisation was performed. Urgent venous arterialisation may be considered as viable alternative in patients with limb acute ischaemia, when arterial reconstruction is impossible to perform. In our case improvement of the foot perfusion during 8 days increases the interest to this technique.

Effects of portal venous arterialization on acute occlusion of hepatic artery in rats

A fatal complication after liver transplantation is anastomotic embolization of the hepatic artery. In order to solve this problem, the portal venous arterialization (PVA) is used to reconstruct the hepatic arterial blood flow. The purpose of this study was to investigate the influence of PVA on rats with acute occlusion of hepatic artery. Rat PVA models were established and then randomly divided into Group 1 (control group), Group 2 (jaundice group), Group 3 (bile duct recanalization group), and Group 4 (portal vein arterilization group). Recanalization of the common bile duct and PVA were performed 5 days after bile duct ligation in the rats. The influence of the PVA on general conditions, hepatic changes of structure and function, portal vein pressure and hepatic micrangium were observed for one month. Five days after common bile duct ligation the serum bilirubin, transaminase and alkaline phosphatase levels were significantly increased. Compared with group 1, there was a statistically significant difference (P < 0.01). These rats then underwent bile duct recanalization and PVA. After a month, the liver functions and microscopic structures completely returned to normal and, compared with group 1, there was no statistically significant difference in portal vein pressure (P > 0.05). Vascular casting samples showed that hepatic sinusoids were slightly thicker and more filled than normal ones and although they had some deformations, the hepatic sinusoids were still distributed around the central vein in radial form. Within a month after operation, bile duct recanalization and PVA do not show obvious adverse effects on liver hemodynamics and hepatic micrangium, and the liver function and microscopic structure can return to normal.

Portal venous arterialization resulting in increased portal inflow and portal vein wall thickness in rats

To explore the influence of portal vein hemo-dynamic changes after portal venous arterialization (PVA) on peribiliary vascular plexus (PVP) morphological structure and hepatic pathology, and to establish a theoretical basis for the clinical application of PVA. Sprague-Dawley rats were randomly divided into control and PVA groups. After PVA, hemodynamic changes of the portal vein and morphological structure of hepatohilar PVP were observed using Doppler ultrasound, liver function tests, ink perfusion transparency management and three-dimensional reconstruction of computer microvisualization, and pathological examination was performed on tissue from the bile duct wall and the liver. After PVA, the cross-sectional area and blood flow of the portal vein were increased, and the increase became more significant over time, in a certain range. If the measure to limit the flow in PVA was not adopted, the high blood flow would lead to dilatation of intrahepatic portal vein and its branches, increase in collagen and fiber degeneration in tunica intima. Except glutamic pyruvic transaminase (GPT), other liver function tests were normal. Blood with a certain flow and oxygen content is important for filling the PVP and meeting the oxygen requirement of the bile duct wall. After PVA, It is the anatomic basis to maintain normal morphology of hepatohilar bile duct wall that the blood with high oxygen content and high flow in arterialized portal vein may fill PVP by collateral vessel reflux. A adequate measure to limit blood flow is necessary in PVA.

Replantation of Completely Amputated Thumbs With Venous Arterialization

To report a new method of replanting completely amputated thumbs with venous arterialization. In 6 replantation surgeries of completely amputated thumbs performed during the period 1999-2003, the proximal artery was anastomosed with a vein of the amputated part to establish inflow and the proximal vein was anastomosed with several other veins in the amputated part to establish outflow. This was because the proper palmar digital arteries were seriously injured or anastomosis of proper palmar digital arteries failed many times. All the replanted thumbs survived, regained good sensory and motor functions, and showed no difference from thumbs replanted conventionally. Venous arterialization may salvage otherwise unreplantable thumbs.

Anatomical basis and short-term effect of in situ coronary venous arterialization

To study the anatomical basis of in situ coronary venous arterialization (ICVA) and to observe the short-term clinical outcome thereof. Five recently isolated pig hearts underwent ligation of the posterior descending artery and the proximal end of middle cardiac vein (MCV), solution of Indian ink was perfused into this vein, and slices of heart were made to observe the distribution of ink through microscope. From January 2002 to December 2005, 64 consecutive patients with diffuse lesion and distal occlusion of right coronary artery received coronary artery bypass grafting (CABG) were randomly divided into 2 equal groups to undergo ICVA during CABG (ICVA group) and conventional CABG only (control group) respectively. The pre- and post-operation clinical data, including ECG, SPECT and ultrasonic cardiograph (UCG) were analyzed. Indian ink was distributed in the intercellular spaces and capillaries of the myocardium and appeared in the micro-arteries in all 5 pig hearts. The mean hospitalization time of the ICVA patients was 16.5 +/- 7.7 days. The mortality rate was 0. After the ICVA the ECG recovery rate in ST segment was 98.88%, and the improvement rate in the grade of the angina was 100%. SPECT and UCG both showed great improvement post-operatively (P < 0.05). After the ligation of the proximal end of MCV, the related myocardium can be perfused effectively by distal arterialization in situ. ICVA, fitting to patients with diffused lesion and distal occlusion of coronary artery, can be performed safely with satisfactory clinical outcomes.

Venous arterialization in extralobar pulmonary sequestration associated with fetal hydrops

Background/Purpose Fetal extralobar pulmonary sequestration (EPS) is sometimes complicated by massive pleural effusion (PE) leading to fetal hydrops. The underlying mechanisms as well as the origin of the fluid are not well understood. This study was performed to find a histological hallmark of an EPS with massive PE. We hypothesized that venous obstruction has a role to play in the mechanisms of fluid production by EPS. Methods We recently experienced 3 cases of fetal EPS complicated by fetal hydrothorax requiring thoracentesis and eventually thoracoamniotic shunt placement. Total protein content and cell count were measured in the aspirates, which were compared with chylothorax cases (n = 5) requiring fetal shunt placement. After birth, all 3 infants required mass resection for the control of PE. The venous wall thickness was measured on pathology slides stained with Elastica van Gieson staining. Thickness of the media and adventitia was measured in approximately 40 veins per case. They were corrected by external diameter and expressed as percentage of medial thickness and percentage of adventitial thickness. An EPS not associated with PE but with congenital diaphragmatic hernia served as a control. Results Total protein and the cell count of the EPS related PE were 0.6 ± 0.3 mg/dL and 28 ± 14/ μL (mean ± SD), which were significantly lower than those of PE in chylothorax (2.2 ± 0.2 mg/dL and 1900 ± 1100/ μL). Percentages of adventitial thickness of EPS with PE were 9.8% ± 3.8%, 10.4% ± 3.6%, and 8.3% ± 3.7%, which were significantly increased compared with the control of 3.1% ± 1.3% ( P < .01). Percentages of medial thickness of EPS with PE were 7.0% ± 1.9%, 7.3% ± 1.4%, and 6.6% ± 2.3%, which were significantly increased compared with the control of 2.3% ± 0.7% ( P < .01). Conclusions We conclude that PE associated with EPS is the transudate rather than the lymph. The thickened media and the adventitia found in EPS with PE support the hypothesis that partial obstruction of the venous system leads to an increased transudate production, which ultimately leads to fetal hydrops.

Neuron Restrictive Silencer Factor NRSF/REST Is a Transcriptional Repressor of Neuropilin-1 and Diminishes the Ability of Semaphorin 3A to Inhibit Keratinocyte Migration

Neuropilin-1 (NRP1) is expressed by endothelial cells and neurons and serves as a receptor for both vascular endothelial growth factor (VEGF), an angiogenesis factor, and semaphorin 3A (Sema3A), a mediator of axonal guidance. We show here that NRP1 is also expressed in keratinocytes in vitro and in vivo. However, nothing has been reported about the regulation or function of keratinocyte NRP1. Using NRP1 promoter constructs in HaCaT cells, a keratinocyte cell line, we could demonstrate that a neuron restrictive silencer element (NRSE) was implicated in transcriptional repression of the NRP1 gene. Electrophoretic mobility shift assays demonstrated that the neuron restrictive silencer factor (NRSF) binds to NRSE. Overexpression of NRSF in HaCaT cells decreased NRP1 RNA and protein, whereas a dominant negative NRSF increased NRP1. Furthermore, the histone deacetylase inhibitor trichostatin A, an inhibitor of NRSF silencing activity, also increased NRP1 levels. NRP2 expression was not affected. Epidermal growth factor (EGF) and heparin-binding EGF-like growth factor (HB-EGF) strongly up-regulated NRP1 expression, concomitant with down-regulation of NRSF. Other keratinocyte mitogens such as keratinocyte growth factor (KGF) had no effect. To address function, HaCaT cells were exposed to two NRP1 ligands, VEGF165 and Sema3A. Neither had an effect on proliferation, whereas Sema3A, but not VEGF165, inhibited cell migration. Down-regulation of NRP1 by NRSF overexpression reduced Sema3A activity. It was concluded that NRSF is a transcription factor that silences NRP1 expression and thereby diminishes the Sema3A mediated inhibition of HaCaT keratinocyte migration.

Treatment of critical ischaemia of the lower limb by venous arterialization : an interim report.

A method to revascularize the critically ischaemic lower limb by arterialization of the dorsal venous arch of the foot via the long saphenous vein is described. Satisfactory procedures were achieved in 5 of 6 patients for whom standard arterial reconstructions were not possible and who would otherwise have required amputation. Of these, 2 failed in the early postoperative period and amputation was performed. Two others failed after 1 year and 18 months respectively but amputation was not required. One patient died 8 months after operation with a functioning arterialized vein and pain-free limb. In the 5 patients with successfully revascularized limbs rest pain was relieved, and incisions, ischaemic ulcers and gangrene healed, showing that effective nutrition of the lower limb was achieved by delivering arterial blood through the venous system. Complications were minor and easily controlled. Although as a result of the procedure amputation was avoided in 3 out of 6 patients, the place of the method in the treatment of critical ischaemia of the lower limb remains dubious. Further investigation and modification of the method are planned.

Percutaneous In Situ Coronary Venous Arterialization: A Catheter‐Based Procedure for Coronary Artery Bypass

Diffuse coronary artery disease is frequently untreatable by coronary artery bypass or angioplasty. Open chest surgical arterialization of the coronary venous system was successfully performed before the widespread use of coronary artery bypass grafting and has been applied in ungraftable patients thereafter. Percutaneous in situ coronary venous arterialization (PICVA) follows this surgical experience, using a series of unique catheter-based devices to arterialize isolated segments of coronary vein, forcing retroperfusion of severely ischemic myocardium. In a series of animals, this procedure had been shown to reduce ischemia and myocardial damage in an infarction model. In the PICVA European Safety trial, the first 11 percutaneous applications of catheter-based coronary bypass in humans revealed feasibility of the technique in highly symptomatic "no-option" patients. Despite two deaths and six failures to create the bypass, we continue to believe that on further development, the catheter-based coronary bypass can become a broad-based interventional application.

Lack of Durability of Surgical Arterialization of Coronary Veins for the Treatment of Ischemic Heart Disease

Coronary venous arterialization with a catheter-based system has renewed interest in this therapy for the revascularization of areas that cannot be treated by conventional coronary artery bypass graft or angioplasty. However, the durability of the venous system to supply arterial pulsatile blood is still a matter of debate. We report the outcome of four patients that underwent elective coronary artery bypass grafting of the left coronary system and in addition had selective arterialization of the posterior vein due to ungraftable poor distal vessels of the right coronary artery. Complete revascularization of the left side was achieved using the left internal mammary artery and the left radial artery. One vein graft was anastomosed to the postero-inferior vein in three cases and to two postero-inferior veins in the fourth case. No perioperative complications were observed and after 24 months of follow-up; all patients were angina free and without any symptoms of heart failure. The 24 months follow-up also showed (i) normal exercise test in all patients, (ii) ischemic changes in dobutamine stress echocardiography in the areas corresponding with the venous arterialization in two cases, and (iii) occlusion of the graft supplying the coronary veins in the three patients that accepted to undergo selective angiogram. In conclusion, these results indicate that arterialization of the coronary veins is not durable and that it is unlikely that this strategy is a useful technique for the revascularization of the ischemic myocardium.

Cranial Dural Arteriovenous Fistulas: Clinical Findings and Radiologic Diagnostics

Cranial dural arteriovenous fistulas (DAVFs) are a unique acquired neurovascular entity, which may develop in the dura mater and adjacent pial veins. These arteriovenous shunting lesions of the dura are quite distinct from archetypal cerebral arteriovenous malformations because of pathologic, pathogenetic, and clinicobiological criteria. There remains some confusion and debate regarding proper nomenclature, pathophysiology, and pathoetiologic mechanisms. Clinical symptoms are highly variable and depend on the specific location of the lesion, the extent of arterial supply, and especially on the specific pattern of venous drainage. The Department of Neuroradiology, Kantonsspital Aarau, Switzerland, has consecutively assessed 185 patients with cranial DAVFs in the last 17 years. Treatment consisted of observational management, surgical resection, transarterial or transvenous embolization, or a combination of these therapies. A group of 95 aggressive cranial DAVFs (Borden grade 2 or 3) was analyzed. In regard to venous pattern of their venous drainage the DAVFs were classified in five groups considering both the location and the possible pathogenesis. The patients with aggressive cranial DAVFs presented with hemorrhage, neurologic deficit, seizure, and dementia. The morphological development of DAVFs seems to depend on the flow volume of the venous recipient. A pronounced generation of pathologic AV shunts usually takes place at the level of large dural sinuses. By contrast, a delayed development of AV shunts with a low shunt volume occurs in a venous recipient with low AV pressure gradients. Transarterial treatment of DAVFs is chosen to improve symptoms and/or to prevent catastrophic consequences of the natural history of this disease. Once the venous side has been occluded, all arterial input (i. e., venous arterialization) will permanently cease. An anatomic cure can be achieved by obliteration of the venous recipient in three fashions: transvenous occlusion of sinus, transvenous occlusion of venous pouch outside the sinus lumen, or transarterial occlusion of venous channel.

Percutaneous approach to a stent-based ventricle to coronary vein bypass (venous VPASS™): comparison to catheter-based selective pressure-regulated retro-infusion of the coronary vein

Percutaneous stent-based ventricle-to-coronary vein bypass (venous VPASS) is a new approach to chronic venous arterialization as a treatment modality in an otherwise no option patient with coronary artery disease. In this study, the efficacy of venous VPASS was compared with catheter-based selective pressure-regulated retro-infusion of arterial blood during acute ischaemia. In seven pigs, venous VPASS was established using a percutaneous ultrasound-guided puncture from the anterior cardiac vein to the left ventricle, with subsequent implantation of an ePTFE-covered stent graft. During left anterior descending artery (LAD) occlusion, coronary venous pressure in the distal anterior cardiac vein increased to 55+/-4 mmHg under conditions of venous VPASS compared with 78+/-5 mmHg during selective pressure-regulated retro-infusion. Significant preservation of regional myocardial function was observed during venous VPASS (67+/-6% baseline) and during selective retro-infusion (83+/-4%) compared with control LAD occlusion (0.4+/-2%). Percutaneous implantation of a PTFE covered stent (venous VPASS) was feasible and associated with significant preservation of regional myocardial function during acute ischaemia in pigs at reasonable levels of mean coronary venous pressure to avoid tissue damage during chronic application.

Catheter-based ventricle-coronary vein bypass

The goal of this study was to investigate the feasibility of a catheter-based ventricle-to-coronary vein bypass (VPASS) in order to achieve retrograde myocardial perfusion by a conduit (VSTENT) from the left ventricle (LV) to the anterior interventricular vein (AIV). Percutaneous coronary venous arterialization has been proposed as a potential treatment strategy for otherwise untreatable coronary artery disease. In an acute setting, the VSTENT implant was deployed percutaneously using the VPASS procedure in five swine. Coronary venous flow and pressure patterns were measured before and after VSTENT implant deployment with and without AIV and left anterior descending artery (LAD) occlusion. In a separate chronic pilot study, the VPASS procedure was completed on two animals that had a mid-LAD occlusion or LAD stenosis. At day 30 post-VPASS procedure, left ventriculography and magnetic resonance imaging (MRI) were performed to assess the patency and myocardial viability of the VSTENT implants. Pre-VSTENT implantation, the mid-AIV systolic wedge pressure was significantly lower than LV systolic pressure during AIV blockage (46 +/- 19 vs. 90 +/- 16 mm Hg; P < 0.01). The VSTENT implant deployment was performed without complication and achieved equalization of the AIV and LV systolic pressures and creation of retrograde flow in the distal AIV (maximal flow velocity: 37 +/- 7 cm/sec). At day 30 post-VPASS procedure, left ventriculography showed VSTENT implant patency. MRI perfusion images demonstrated myocardial viability even with an LAD occlusion. Coronary retrograde perfusion using the VPASS procedure is feasible and may represent a potential technique for end-stage myocardial ischemia.

A Novel Approach: Ascending Venous Arterialization for Atherosclerosis Obliterans

Objective Lower limb arterial occlusion with no patent distal artery suitable for revascularisation is a common problem. The aim of this study was to assess the role of revascularisation to distal veins (ascending venous arterialization) in patients not reconstructable by conventional bypass. Method Ascending venous arterialization is a distal arteriovenous fistula. Reversed great saphenous vein grafts, from above the knee, were anastomosed to the common femoral artery, superficial femoral artery or popliteal artery and distally to the saphenous vein at the level of medial malleolus. No intervention was done to destroy the venous valves. The great saphenous vein was ligated below the knee. In this way, oxygenated blood could reach to dorsal venous arch and the tissues below the knee in an ascending fashion through the great saphenous vein, which was not removed. Results All of the patients recovered immediately after the operation. The lesions on the feet and on the toes of the patients improved in a short time. Intermittent claudication of the patients disappeared. Strong pulses were detected on the dorsal venous arch with manual Doppler in 3 weeks. The below knee tissues were perfused with the applied technique. Conclusion Ascending venous arterialization can be applied for limb salvage to the patients who do not have a suitable arterial bed to revascularize with conventional techniques.