Venous Bypass Research Articles

High-flow arteriovenous fistula resulting from stingray injury.

Stingray punctures are relatively common in several coastal regions and may result in chronic wounds and disability due to injury and envenomation. Vascular complications are rare but can be severe. We describe a case of high-flow arteriovenous fistula resulting from a stingray injury that required a venous bypass.

Vacuum-Implemented Removal of Lead Vegetations in Cardiac Device-Related Infective Endocarditis.

When approaching infected lead removal in cardiac device-related infective endocarditis (CDRIE), a surgical consideration for large (>20 mm) vegetations is recommended. We report our experience with the removal of large CDRIE vegetations using the AngioVac system, as an alternative to conventional surgery. We retrospectively reviewed all infected lead extractions performed with a prior debulking using the AngioVac system, between October 2016 and April 2022 at our institution. A total of 13 patients presented a mean of 2(1) infected leads after a mean of 5.7(5.7) years from implantation (seven implantable cardioverter-defibrillators, four cardiac resynchronization therapy-defibrillators, and two pacemakers). The AngioVac system was used as a venous–venous bypass in six cases (46.2%), venous–venous ECMO-like circuit (with an oxygenator) in five (38.5%), and venous–arterial ECMO-like circuit in two cases (15.4%). Successful (>70%) aspiration of the vegetations was achieved in 12 patients (92.3%) and an intraoperative complication (cardiac perforation) only occurred in 1 case (7.7%). Subsequent lead extraction was successful in all cases, either manually (38.5%) or using mechanical tools (61.5%). The AngioVac system is a promising effective and safe option for large vegetation debulking in CDRIE. Planning the extracorporeal circuit design may represent the optimal strategy to enhance the tolerability of the procedure and minimize adverse events.

Myeloid PHD2 conditional knock-out promotes vein graft plaque stability by reducing vessel wall M1 macrophages and intraplaque haemorrhage

Background and Aims : Revascularization interventions using venous bypass grafts are hampered by high failure-rates. Inflammation and intraplaque-angiogenesis are key drivers of vein graft failure and is mediated by macrophages. PHD proteins regulate cellular responses to hypoxia (with PHD2 as the most important regulator), possibly altering macrophage function as well as intraplaque angiogenesis in the hypoxic vein graft wall. We therefore aim to investigate the effect of myeloid PHD2 on plaque stability in hypoxic, atherosclerotic vein grafts.

Wall Shear Stress Differences Between Arterial and Venous Coronary Artery Bypass Grafts One Month After Surgery.

Although coronary artery bypass graft (CABG) surgery is a well-established intervention, graft failure can occur, and the underlying mechanisms remain incompletely understood. The purpose of this prospective study is to utilize computational fluid dynamics (CFD) to investigate how graft hemodynamics one month post surgery may vary among graft types, which have different long-term patency rates. Twenty-four grafts from 10 participants (64.6 ± 8.5years, 9 men) were scanned with coronary CT angiography and 4D flow MRI one month after CABG surgery. Grafts included 10 left internal mammary arteries (LIMA), 3 radial arteries (RA), and 11 saphenous vein grafts (SVG). Image-guided CFD was used to quantify blood flow rate and wall area exposed to abnormal wall shear stress (WSS). Arterial grafts had a lower abnormal WSS area than venous grafts (17.9% vs. 70.1%; p = 0.001), and a similar trend was observed for LIMA vs. SVG (13.8% vs. 70.1%; p = 0.001). Abnormal WSS area correlated positively to lumen diameter (p < 0.001) and negatively to flow rate (p = 0.001). This CFD study is the first of its kind to prospectively reveal differences in abnormal WSS area 1month post surgery among CABG types, suggesting that WSS may influence the differential long-term graft failure rates observed among these groups.

Double Trouble! Concomitant Ipsilateral Symptomatic Popliteal Venous Aneurysm

A 50 year old woman presented with calf oedema, pain, and paraesthesia of 48 hours duration. A duplex ultrasound scan showed a partially thrombosed popliteal venous aneurysm. Computed tomography angiography (CTA) revealed two isolated popliteal venous aneurysms (diameters of 28 and 16 mm, respectively) involving the same popliteal vein (A, arrows), with inner thrombus. CTA also identified a double system, with another non-thrombosed, non-aneurysmal popliteal vein. Resection of the venous segment, including both venous aneurysms, was performed (B). No reconstruction (e.g., venous bypass) was required because of the double venous system. The post-operative course was uneventful.Image 1

Coronary Artery Bypass Grafting In Young Patients: A Retrospective Review at Queen Alia Heart Institute

Background: Coronary artery bypass grafting (CABG) is the ‘Gold Standard’ for patients with multiple vessel coronary artery disease (CAD). Younger patients presenting with coronary artery disease requiring surgery may represent a distinct subgroup with the main goal for coronary revascularization being long term patency of the performed grafts to improve outcome. Objective: The aim of this study was to check if young patients need surgery urgently for operative revascularization or electively. Also, check the potential advances regarding long-term patency using combined venous and arterial revascularization, and finally the overall mortality in young group of patients after CABG. Methods: Between January 2018 to January 2022, 526 patients below the age of 50 years underwent Coronary Artery Bypass Grafting CABG for coronary artery disease CAD in Queen Alia Heart Institute QAHI, We retrospectively analyzed the perioperative data and evaluated patients’ outcome. Results: In 25% of the patients, CABG was performed as an emergency procedure for STEMI or NSTEMI within 36 hours. Another 27% of the patients were operated urgently for unstable angina or myocardial infarction within the last weeks and only 48% of the patients were purely elective cases. We performed only venous bypass grafts in 12%, and combined venous and arterial revascularization in 88%. Patients received 2.8 ± 1 bypass grafts overall. Overall in-hospital mortality in this cohort was low with 1% (n = 1). Conclusions: The majority of the young patients below the age of 50 years present urgently for operative revascularization. Besides, the potential advances regarding long-term patency using total arterial revascularization, only about half of the young patients are feasible for this approach. Overall, early outcome in this group is excellent with mortality below one percent.

Is open surgery still the first line of treatment for long femoropopliteal lesions?

Treatment of long femoropopliteal lesions remains a challenge for vascular physicians as patients often present with multilevel complex pathologies and consequently face a high amputation risk and associated mortality. This review aimed to assess the current state of optimal revascularizations for the treatment of long femoropopliteal lesions. An online literature research of medical databases for original articles and review articles on open and endovascular revascularization of femoropopliteal lesions was conducted using mesh terms. There has been an accumulation of evidence over the last years that endovascular treatment is a feasible and enduring alternative to open surgery for treatment of long femoropopliteal lesions if the lesions are restricted to the superficial femoral artery. But when disease extends to the infragenual level venous bypass remains superior with regards to long-term patency, clinical improvement and limb-salvage. While the role of venous bypass as a first-line treatment might be declining, especially in frail patients or claudicants, the superior clinical improvement and amputation-free survival highlighted in several trials, demonstrate the relevance of bypass surgery. More randomized clinical trials are needed to verify the non-inferiority of endovascular treatment options to open surgery, especially when arterial disease extends below the knee.

A surgical method to be reminded for the treatment of symptomatic ipsilateral central venous occlusions in patients with hemodialysis access: Axillo-axillary venous bypass case report and review of the literature.

In this case report, we present two chronic hemodialysis patients with upper extremity swelling due to central venous occlusions together with their clinical presentation, surgical management and brief review of the literature. The first patient who was a 63-year-old female patient with a history of multiple bilateral arteriovenous fistulas (AVFs) was referred to our clinic. Physical examination demonstrated a functioning right brachio-cephalic AVF, with severe edema of the right arm, dilated venous collaterals, facial edema, and unilateral breast enlargement. In her history, multiple ipsilateral subclavian venous catheterizations were present for sustaining temporary hemodialysis access. The second patient was a 47-year-old male with a history of failed renal transplant, CABG surgery, multiple AV fistula procedures from both extremities, leg amputation caused by peripheral arterial disease, and decreased myocardial functions. He was receiving 3/7 hemodialysis and admitted to our clinic with right arm edema, accompanied by pain, stiffness, and skin hyperpigmentation symptoms ipsilateral to a functioning brachio-basilic AVF. He was not able to flex his arms, elbow, or wrist due to severe edema. Venography revealed right subclavian vein stenosis with patent contralateral central veins in the first patient. She underwent percutaneous transluminal angioplasty (PTA) twice with subsequent re-occlusions. After failed attempts of PTA, the patient was scheduled for axillo-axillary venous bypass in order to preserve the AV access function. In second patient, venography revealed right subclavian vein occlusion caused secondary to the subclavian venous catheters. Previous attempts for percutaneously crossing the chronic subclavian lesion failed multiple times by different centers. Hence, the patient was scheduled for axillo-axillary venous bypass surgery. In case of chronic venous occlusions, endovascular procedures may be ineffective. Since preserving the vascular access function is crucial in this particular patient population, venous bypass procedures should be kept in mind as an alternative for central venous reconstruction, before deciding on ligation and relocation of the AVF.

A Century With Craniopagus Twin Separation Surgeries: Nihilism to Optimism.

Craniopagus conjoined twins are extremely rare, reported 1 in 2.5 million live births. To date, 62 separation attempts in 69 well-documented cases of craniopagus twins have been made. Of these, 34 were performed in a single-stage approach, and 28 were attempted in a multistage approach. One or both twins died of massive intraoperative blood loss and cardiac arrest in 14 cases. We report our surgical experience with conjoined craniopagus twins (JB) with type III total vertical joining and shared circumferential/circular sinus with left-sided dominance. A brief review of the literature is also provided. In our twins, the meticulous preoperative study and planning by the multidisciplinary team consisting of 125-member, first-staged surgical separation consisted of creation of venous conduit to bypass part of shared circumferential sinus and partial hemispheric disconnection. Six weeks later, twin J manifested acute cardiac overload because of one-way fistula development from blocked venous bypass graft necessitating emergency final separation surgery. Unique perioperative issues were abnormal anatomy, hemodynamic sequelae from one-way fistula development after venous bypass graft thrombosis, cardiac arrest after massive venous air embolism requiring prolonged cardiopulmonary resuscitation, and return of spontaneous circulation at 15 minutes immediately after separation. This is the first Indian craniopagus separation surgery in a complex total vertical craniopagus twin reported by a single-center multidisciplinary team. Both twins could be sent home, but one remained severely handicapped. Adequate perioperative planning and multidisciplinary team approach are vital in craniopagus twin separation surgeries.

Abstract 482: Early Reduction of Blood Flow in Rabbit Jugular Vein-Carotid Artery Bypass Grafts is not Caused by Anastomotic Stenosis

Background: Obstructed arteries are often treated by surgical implantation of venous bypass grafts. Vein grafts can fail for many reasons, including thrombosis, atherosclerosis, or anastomotic stenoses (narrowings where the grafts connect to the artery). In a previous study aimed at developing a hyperlipidemic rabbit model of vein-graft atherosclerosis for testing gene therapy, vein grafts used to bypass carotid arteries were widely patent. However, vein graft blood flow decreased by a mean of 5.6 mL/minute (~23%) between 8 and 16 wks after grafting, with flow at 16 wks reduced to &lt;60% of flow in an unoperated carotid artery. We hypothesized that decreased flow was caused by anastomotic stenoses, raising concern that this might lead to graft occlusion, precluding use of the model to test gene therapy for atherosclerosis. Methods: We designed an experiment to test whether anastomotic stenoses were present and—if so—whether the stenoses were the cause of decreased blood flow. In a new set of grafted veins, we harvested the anastomoses, embedded, sectioned and stained them, and measured percent stenosis using computer-assisted image analysis. Percent stenosis was calculated by dividing intimal area by the stenosis-free lumen area (calculated from the length of the IEL, assuming circular geometry in vivo). We measured stenoses in both anastomoses of 22 patent vein grafts, harvested from 14 hyperlipidemic rabbits (44 total anastomoses). Blood flow (mL/min) in each vein graft was measured with a flow meter at 4 wks after grafting and again at 16 wks (at harvest). Results: The mean blood flow at the 4 wks measurement was 51 mL/minute (range: 28 to 90) and 36 mL/minute (range: 21 to 53) at the harvest measurement. The calculated mean change in blood flow was –16 mL/minute (range: –55 to +14). The mean anastomotic stenosis was 39% (range: 2.3% to 89%). Using Spearman’s rank-order correlation test, we found that percentage stenosis did not correlate with the change in blood flow (r=0.059; P=0.8). Conclusions: Decreased blood flow in our vein graft model is likely not caused by anastomotic stenoses. Other explanations, such as decreased cardiac output or increased downstream vascular resistance (caused by cerebral atherosclerosis or microemboli) should be considered.

Abstract 444: Apolipoprotein A-I (ApoAI) Vascular Gene Therapy Protects Against Vein-Graft Atherosclerosis

Introduction: Coronary artery venous bypass grafts typically fail because of accelerated atherosclerosis, driven by lipid infiltration and by accumulation of macrophages and other cells. We previously showed that transduction of carotid artery endothelium of fat-fed rabbits with a helper-dependent adenovirus expressing apolipoprotein AI (HDAdApoAI) reduced atherosclerotic lesion size and decreased intimal lipid and macrophage accumulation. We hypothesized that HDAdApoAI transduction of rabbit vein graft endothelium would reduce lipid and macrophage accumulation. Methods: Fat-fed rabbits received bilateral external jugular vein to carotid artery interposition grafts. Four wks later, one graft per rabbit was infused with HDAdApoAI and the other with HDAdNull (a non-expressing HDAd). Grafts were harvested 12 wks after HDAd infusion. Paired analysis was performed in all rabbits with bilateral patent grafts (n=22). Graft hemodynamics were measured at vector-infusion and harvest surgeries. In vivo graft diameters were measured before vector infusion and harvest with ultrasound. Grafts were cut into 8 segments, for histology and biochemical analyses. Results: Mean plasma cholesterol levels were 400-600 mg/dL. Graft patency rates were 89% after vein grafting and 100% after the vector-infusion surgery. Lumen diameter and hemodynamics did not differ between HDAdApoAI and HDAdNull-transduced grafts. HDAd genomes were detected in all vein grafts. High levels of apoAI mRNA were detected in 100% of HDAdApoAI-treated vein grafts (mean 155-fold higher than in HDAdNull grafts). HDAdApoAI-treated grafts had 25% lower cholesterol (by mass spectrometry; P=0.03) and 17% less median CD68 mRNA (by RT-qPCR; P=0.008; CD68 is expressed by macrophages and lipid-loaded SMC). No significant differences were detected in mRNA encoding several inflammatory cytokines and inflammation-associated proteins. There were nominal decreases in total intimal area (16%, P=0.9), percent stenosis (4%, P=0.08), and in intimal area positive for Oil Red O (11%, P=0.3), macrophages (11%, P=0.7), and VCAM-1 (8%, P=0.8). Conclusion: HDAdApoAI transduction of vein graft endothelium reduces some markers of atherosclerosis, potentially by stimulating cholesterol efflux.

Multiple concomitant arterial aneurysms in Behçet's disease.

Behçet's disease (BD) is a rare form of systemic vasculitis that affects small to large vessels. It is characterized by mucocutaneous, pulmonary, cardiovascular, gastrointestinal, and neurological manifestations. Large vessel involvement may occur in a third of cases. Veins are usually more affected than arteries. Furthermore aneurysms are the most frequent arterial complication. A 41-year-old man presented with multiple arterial aneurysms. He had previous medical history of a right popliteal aneurysm treated with a reversed femoro-popliteal venous bypass, long-term steroids and immunosuppressive treatment. On admission, diagnostic computed tomography angiography revealed multiple aneurysms, including an 87mm aneurysm of the femoro-popliteal bypass and an abdominal aortic and left common iliac artery aneurysm. He received an intensification of medical treatment with methylprednisolone and infliximab intravenous infusion. Aorto iliac artery aneurysms were treated by infrarenal bifurcated stent graft implantation. The aneurysm of the venous femoro-popliteal bypass was treated by explantation and prosthetic repair. One month later, he presented with acute right limb ischemia related to occlusion of the right limb of the stent graft despite anticoagulation which was treated by mechanical thrombectomy. Vascular BD can worsen the vascular outcome after surgery. Except in an urgent context, BD must be controlled before surgery. This case report illustrates the importance of combined medical and surgical management, with first BD activity control with corticosteroids and immunosuppressive treatment, then surgical or endovascular treatment.

Portocaval shunt and its Implications for Liver Transplantation: An Integrative Literature Review

Abstract:Introduction: Portal vein clamping can generate splanchnic venous congestion and increase portal hypertension, causing release of inflammatory mediators in liver transplantation. The venous bypass technique was developed at the beginning to avoid congestion. In 1968, the piggyback technique was described, and in 1993 and 1995, the temporary portocaval shunt (TPCS) was described as an alternative to preserve the flow of the vena cava and the intraoperative portal system. With the expansion of the number of living transplants, an adaptation of the anastomosis, or temporary hemi portocaval shunt (THPCS) was developed. Objective:This review aimed to analyze the literature found in the TPCS and THPCS databases in adult liver transplantation. Methods: Integrative review carried out through searches in PubMed, Online Scientific Electronic Library (SciELO) and Literatura Latino-Americana e do Caribe em Ciências da Saúde (Lilacs) databases, with 15 articles published in the last 12 years (2010-2021) being selected, after applying criteria defined by the authors and including three works for historical reference. Results: The increase in surgery time does not seem to be a significant disadvantage that justifies contraindication to the use of portocaval anastomosis during the procedure. In transplantation, there is an indication that the TPCS improves hemodynamic stability, with reduced infusion of packed red blood cells and platelets. Data on postoperative levels of aminotransferase, aspartate aminotransferase, and international normalized index were conflicting, with improvement in renal function as assessed by creatinine measurement. The studies demonstrate a relationship between TPCS and a decrease in hospital stay. It was not possible to reach a conclusion regarding the impacts on survival after transplantation. THPCS appears to be effective in decreasing portal flow, serving its purpose of preventing hyperflow, however it does not appear to be an absolute guarantee of preventing complications. The biggest perceived limitation was the heterogeneity of the studies included in this review. Conclusion: The developed studies point to benefits in hemodynamic stability and postoperative renal function and shorter hospital stay. It was not possible to conclude about the impact of the technique on liver injury, overall survival or graft survival, due to divergences in the literature.

Abstract 12376: Coronary Artery Bypass Graft Surgery in Spontaneous Coronary Artery Dissection

Introduction: Spontaneous coronary artery dissection (SCAD) is a nonatherosclerotic cause of acute coronary syndrome. While most patients are managed conservatively, some patients may require percutaneous or surgical revascularization. Limited data exist on SCAD patients referred for coronary artery bypass graft (CABG) surgery. Hypothesis: Examine the clinical characteristics, management, and outcomes of SCAD patients referred for CABG. Methods: Retrospective study of patients enrolled in the Mayo Clinic SCAD Registry between 2010-2020 who underwent CABG during the initial management of acute SCAD episode. Results: Among the 81 patients with SCAD referred for CABG, 3 (4%) were men, mean age was 40.6 +/- 8.4 years; the majority were white (91%), and 24 (30%) had pregnancy-associated SCAD (P-SCAD). The most common presenting symptom was chest pain 80 (99%); 57 (70%) presented with ST elevation myocardial infarction (STEMI), and 21 (26%) presented with non-ST elevation MI. Multivessel dissection occurred in 40 (49%), left anterior descending artery (LAD) involvement occurred in 66 (81%) and left main (LM) in 32 (40%). Left ventricular ejection fraction was &lt;50% in 40 patients (49%) at time of initial SCAD. The most common reasons for CABG were the presence of high-risk anatomy (56%), hemodynamic instability/active ischemia (7%), failed PCI (9%), and other/unknown (12%). Most patients received venous plus arterial bypass grafts 42 (52%), saphenous vein grafts in 20 (25%), and left internal mammary artery in 17 (21%). Screening for underlying arteriopathy was performed in 50 (62%) of whom 29 (36%) had fibromuscular dysplasia. Recurrent SCAD occurred in 10 (12%) after an average of 6.2 +/- 5 years after initial SCAD. Of those with recurrent SCAD, none required repeat surgical revascularization and 6 required percutaneous intervention (PCI). There were no deaths. Conclusions: Patients undergoing CABG for SCAD commonly present with STEMI, LM, or multivessel dissection, and failed percutaneous intervention attempts. In addition, CABG for P-SCAD was more frequent than expected and may relate to the increased prevalence of multivessel dissection. CABG was associated with low mortality, but recurrent SCAD may still occur.

Peculiarities of surgical tactics of patients with thymus tumors

The aim of the study: to study retrospective analysis results of the surgical treatment of thymus tumours for predicting long-time results.&#x0D; Methods. Study included 35 patients who were treated at the Department of Thoraco-abdominal Surgery from September 2019 to May 2021. The control group included 20 patients with SVCS were treated with conventional techniques, while the experimental group included 15 patients who underwent a novel bypass surgery developed by us.&#x0D; Results. The venous bypass was mandatorily complemented with cytoreduction. Complications in the post-operative period were reported from the experimental group and included auriculo-subclavian bypass thrombosis, post-operative complications were reported in the control group including haemorrhage from the sternotomy wound in 1 (3.3 %) case, superior vena cava thrombosis in 2 (6.6 %) cases, pneumonia in 2 (6.6 %). The relative risk of complications and lethal outcome was calculated for patients from both groups. It was found that the risk of complications was twice as high in the control group as in the experimental group (standard error of relative risk equals 0.64).&#x0D; Conclusion. The first mandatory step of the radical surgery in patients with thymomas with SVC invasion should be the auriculo-jugular and auriculo-subclavian bypasses, which can reduce the relative risk of post-operative complications by a factor of the risk of lethal by a factor of 3.5

Оценка эффективности интенсивной терапии гепатоспланхнической ишемии при политравме под контролем значений pH интрамукозного

Цель исследования: обоснование и внедрение в интенсивную терапию гепатоспланхнической ишемии при политравме эмпирической реоксигенации общего и локального действия. В исследование включены 85 пострадавших с политравмой, в структуру которой входила черепно-мозговая травма: по современной клинической классификации — ушиб головного мозга легкой и средней степени тяжести. Условия для включения в исследование: наличие более 32 баллов по шкале тяжести повреждений — Inyuri Severity Score (ISS), тяжесть состояния по шкале Acute Physiology and Chronic Health Evaluation (APACHE ІІ) — 25 и более баллов. Клинико-биохимические исследования проводили на следующих этапах: при поступлении (1-й этап), через 12–24 часа после начала интенсивной терапии (2-й этап), 3-и, 5-е, 7-е сутки (3, 5, 7-й этапы соответственно). Клиническое наблюдение осуществляли до 32 суток от момента травмы. При поступлении в стационар наблюдались определенные отличия в зависимости от исхода заболевания. У пострадавших с последующим летальным исходом были выше кровопотеря (на 27,65 %, р &lt; 0,05), дефицит объема циркулирующей крови (на 33,42 %, р &lt; 0,05), более выраженные гипотония, тахикардия; возрастали артериальная гипоксемия; показатель венозного шунтирования крови в легких значительно превышал значения в группе выживших и физиологическое шунтирование. При сигмоидальной газовой тонометрии у выживших пострадавших рН интрамукозный находился в пределах 6,88–7,0 ед.; рСО2 от 85,6 до 118,38 мм рт.ст. У умерших рН интрамукозный колебался от 6,79 до 6,9 ед.; рСО2 — от 95,61 до 121,71 мм рт.ст. В 85 % случаев фиброгастродуоденоскопической визуализацией определялись эрозивно-язвенные изменения слизистой оболочки антрального отдела желудка. Гастроинтестинальная недостаточность у пострадавших с последующим летальным исходом клинически соответствовала II–III стадии; по проявлениям гистологических изменений в слизистой оболочке антрального отдела желудка — III–IV стадии. В основе описанных особенностей лежит преобладание у умерших пострадавших значений шкал ISS на 11,77 %, APACHE II на 20,78 % и SOFA на 74,52 %, определяющих тяжесть повреждения, состояние пострадавших, степень выраженности органных повреждений. Начиная с 1-х суток интенсивной терапии различия между изучаемыми показателями у выживших и умерших пострадавших продолжали усугубляться. У выживших пациентов с 1-х суток восстанавливалась оксигенация артериальной крови до физиологических значений, что обусловлено устранением венозного шунтирования крови в легких, переходом к нормодинамическому типу кровообращения. Уже на 3-и сутки рН интрамукозный составил 99,59 % от нормы. У умерших восстановление индекса оксигенации на 1-е сутки сочеталось со снижением тканевой экстракции кислорода, гиповолемическим шоком, рефрактерным к вазопрессорной терапии с 3-х суток исследования. Значения рН превышали 7,35 ед. лишь к 5-м суткам, при этом клинически функция пищеварения не восстановилась и на 7-е сутки исследования. Данные клинической оценки гастроэнтеральной недостаточности нашли свое подтверждение в фиброгастроскопической картине, данных гистологического и гистохимического исследования слизистой оболочки антрального отдела желудка. Установлена высокая, положительная, достоверная корреляционная зависимость между рН интрамукозным и исходом заболевания. Фактическая летальность по промежуточным точкам составила 20 %: на 3-и сутки умерли 3 пострадавших, на 5-е сутки — 2 пострадавших. До 28-х суток клинического наблюдения фактическая летальность составила 44 %: с 7-х по 28-е сутки умерли еще 6 пострадавших. С 28-х по 32-е сутки летальность не зарегистрирована. То есть фактическая летальность по конечным точкам исследования составила 44 %, что ниже предполагаемой летальности приблизительно на 7 %.

Percutaneous coronary intervention of totally occluded coronary venous bypass grafts: An exercise in futility?

BACKGROUNDPercutaneous coronary intervention (PCI) of diseased saphenous vein grafts (SVG) continues to pose a clinical challenge. Current PCI guidelines give a class III recommendation against performing PCI on chronically occluded SVG. However, contemporary outcomes after SVG intervention have incrementally improved with distal protection devices, intracoronary vasodilators, drug-eluting stents, and prolonged dual antiplatelet therapy. AIMTo reassess the procedural and long-term outcomes of PCI for totally occluded SVG with contemporary techniques.METHODSThis was a retrospective observational study conducted at a single university hospital. The study population consisted of 35 consecutive patients undergoing PCI of totally occluded SVG. Post-procedure dual antiplatelet therapy was continued for a minimum of one year and aspirin was continued indefinitely. Clinical outcomes were assessed at a mean follow-up of 1221 ± 1038 d. The primary outcome was freedom from a major adverse cardiac event (MACE) defined as the occurrence of any of the following: death, myocardial infarction, stroke, repeat bypass surgery, repeat PCI, or graft reocclusion. RESULTSThe study group included 29 men and 6 women with a mean age of 69 ± 12 years. Diabetes was present in 14 (40%) patients. All patients had Canadian Heart Classification class III or IV angina. Clinical presentation was an acute coronary syndrome in 34 (97%) patients. Mean SVG age was 12 ± 5 years. Estimated duration of occlusion was acute (< 24 h) in 34% of patients, subacute (> 24 h to 30 d) in 26%, and late (> 30 d) in 40%. PCI was initially successful in 29/35 SVG occlusions (83%). Total stent length was 52 ± 35 mm. Intraprocedural complications of distal embolization or no-reflow occurred in 6 (17%) patients. During longer term follow-up, MACE-free survival was only 30% at 3 years and 17% at 5 years.CONCLUSIONPCI of totally occluded SVG can be performed with a high procedural success rate. However, its clinical utility remains limited by poor follow-up outcomes.

Impact of chronic kidney disease on the outcomes of infrapopliteal venous, and heparin-bonded expanded polytetrafluoroethylene bypass surgeries: A retrospective cohort study.

The aim of this study was to analyze the results of infrapopliteal venous and prosthetic bypass surgeries for patients with chronic limb-threatening ischemia (CLTI) and moderate to severe chronic kidney disease (CKD). All consecutive patients undergoing infrapopliteal bypass surgeries at two academic vascular centers between March 2002 and November 2018 were included in this retrospective study. During this timeframe, infrapopliteal grafts were performed for 487 patients. Of these patients, 160 (32.9%; group 1) had normal renal function, 248 (50.9%; group 2) had moderate CKD, and 79 (16.2%; group 3) had severe CKD according to the Kidney Disease Improving Global Outcomes guidelines. After 5 years' follow-up, the primary patency rate was 46.0% and the secondary patency rate was 54.9% without statistical significance noted between the CKD groups. Limb salvage (65.3%, p = 0.024) and long-term survival (19.6%, p < 0.001) were considerably lower in patients with severe CKD. In subgroup analysis, vein grafts had significantly better long-term patency rates compared to prosthetic grafts, regardless of CKD group. However, in patients with severe CKD, patency rates of vein and heparin-bonded expanded polytetrafluoroethylene (HePTFE) grafts were comparable at the 1-year mark. Our study shows that autologous vein grafts remain the first choice for infrapopliteal bypass surgeries in patients with CKD. HePTFE grafts showed good short-term results in patients with severe CKD. Given the short life expectancy of these high-risk patients, prosthetic HePTFE grafts may be reasonable in this population if a suitable vein is absent.

PFKFB3 gene deletion in endothelial cells inhibits intraplaque angiogenesis and lesion formation in a murine model of venous bypass grafting

Vein grafting is a frequently used surgical intervention for cardiac revascularization. However, vein grafts display regions with intraplaque (IP) angiogenesis, which promotes atherogenesis and formation of unstable plaques. Graft neovessels are mainly composed of endothelial cells (ECs) that largely depend on glycolysis for migration and proliferation. In the present study, we aimed to investigate whether loss of the glycolytic flux enzyme phosphofructokinase-2/fructose-2,6-bisphosphatase 3 (PFKFB3) in ECs inhibits IP angiogenesis and as such prevents unstable plaque formation. To this end, apolipoprotein E deficient (ApoE−/−) mice were backcrossed to a previously generated PFKFB3fl/fl Cdh5iCre mouse strain. Animals were injected with either corn oil (ApoE−/−PFKFB3fl/fl) or tamoxifen (ApoE−/−PFKFB3ECKO), and were fed a western-type diet for 4 weeks prior to vein grafting. Hereafter, mice received a western diet for an additional 28 days and were then sacrificed for graft assessment. Size and thickness of vein graft lesions decreased by 35 and 32%, respectively, in ApoE−/−PFKFB3ECKO mice compared to controls, while stenosis diminished by 23%. Moreover, vein graft lesions in ApoE−/−PFKFB3ECKO mice showed a significant reduction in macrophage infiltration (29%), number of neovessels (62%), and hemorrhages (86%). EC-specific PFKFB3 deletion did not show obvious adverse effects or changes in general metabolism. Interestingly, RT-PCR showed an increased M2 macrophage signature in vein grafts from ApoE−/−PFKFB3ECKO mice. Altogether, EC-specific PFKFB3 gene deletion leads to a significant reduction in lesion size, IP angiogenesis, and hemorrhagic complications in vein grafts. This study demonstrates that inhibition of endothelial glycolysis is a promising therapeutic strategy to slow down plaque progression.

Efficacy of Rivaroxaban and Aspirin in Patients With Peripheral Artery Disease With Venous and Prosthetic Surgical Bypass Conduits: Insights from the VOYAGER PAD Trial

Patients with peripheral artery disease (PAD) requiring surgical lower extremity revascularization (LER) are at heightened risk of adverse limb complications, including acute limb ischemia (ALI). VOYAGER PAD demonstrated that rivaroxaban significantly reduces this risk. Bypass is a major component of surgical LER, and procedural success is dependent on quality and type of conduit. The risk of ALI and efficacy of rivaroxaban for VOYAGER PAD surgical patients receiving vein or prosthetic conduit have not been described.