Superior Mesenteric Artery (SMA) syndrome

Background Atrial fibrillation (AF) is the most common cardiac arrhythmia, affecting up to 10% of the elderly. Ischemic stroke is the main complication of AF and cardioembolism is one of the leading causes of ischemic stroke, accounting for approximately one third of cases. Oral anticoagulant therapy (OAC) is a cornerstone in stroke prevention in patients with AF. According to randomized controlled trials of direct oral anticoagulants, a residual risk of ischemic stroke of 1-2% per year for so-called "breakthrough stroke" remains, despite adequate intake of OAC. The majority (\>70%) of these breakthrough strokes are cardioembolic in nature and only a minority are related to medication issues (e.g. non-compliance) or other, non-AF related etiologies. Stroke recurrence risk after such a breakthrough stroke markedly increases to 8-9% per year indicating a particularly high-risk situation. Why OAC fails in certain patients, but not in others remains as poorly understood, as does the reason why the subsequent risk of stroke is so high. Current risk stratification tools, such as the widely used CHA2DS2-VA(Sc)-score, fail to predict stroke risk in such a high-risk cohort, as they were intended to guide the initiation of OAC in low to moderate risk patients. In light of new therapeutic strategies currently being investigated, such as percutaneous left atrial appendage occlusion in patients with breakthrough strokes (ELAPSE - NCT05976685) or in AF-patients deemed high-risk (LAAOS IV - NCT05963698), improved risk stratification and characterization of high-risk AF patients is highly warranted. Several clinical factors, such as those reflected in the CHA2DS2-VA(Sc)-score, and especially a high AF-burden are associated with increased risk of cardioembolic stroke. Several cardiac serum biomarkers are thought to be surrogates not only of cardiac function, but also of cardioembolic risk. Reflecting ventricular and atrial wall tension, myocardial injury, oxidative stress and thrombogenicity, elevated NT-proBNP, MR-proANP, high-sensitive Troponin T and D-Dimers have all been associated with cardioembolic stroke in different AF and non-AF populations. As the main location of thrombus formation, the left atrium (LA) and more specifically its appendage (LAA) are of particular interest in the pathogenesis of cardioembolism. Pronounced LA-enlargement, compared to a normal-sized LA, correlates with an increased risk of cardioembolism in AF-patients. As over 80% of thrombi form within the LAA, several LAA-characteristics, such as slower LAA-flow velocity and larger LAA-orifice area have also been demonstrated to be associated with higher stroke risk. Although there is data on each one of these factors, they have only been investigated in low to moderate risk populations, such as AF-patients without prior stroke, OAC-naïve patients, or even within the general population as a whole. Their role in high-risk AF-patients and in breakthrough stroke is unknown. Hypothesis The investigators hypothesize that specific clinical factors, serum cardiac biomarkers and markers of LA- and LAA-morphology and function are associated with breakthrough stroke / OAC-failure and may improve risk stratification. Methods CARE-AF is a single-center, prospective cohort study conducted at the Stroke Center of the Inselspital, University Hospital Bern, Switzerland. Patients with an index ischemic stroke and AF (breakthrough and non-breakthrough cases) will be enrolled. The investigators will collect clinical data, serum cardiac biomarkers and echocardiographic indices of the LA and LAA. All patients will receive standardized annual follow-ups until the end of the study, defined as 12 months after the inclusion of the last participant. The primary endpoint is ischemic stroke or systemic embolism during follow-up. First, in a cross-sectional design, the study will assess the association between serum cardiac biomarkers and echocardiographic indices among patients with breakthrough vs. non-breakthrough stroke as index event, applying multivariate regression models. Second, the investigators will perform a longitudinal analysis assessing the association between the variables mentioned above and breakthrough stroke as index event with the primary endpoint, using multivariate Cox regression models. The study aims to enroll a minimum of 500 patients, which provides sufficient power to detect a clinically meaningful adjusted hazard ratio for recurrent stroke of 1.5 with 80% power at an alpha level of 5%. Conclusion The results of this project will enhance understanding of the role of specific clinical factors, cardiac serum biomarkers and echocardiographic indices in the residual risk of stroke in patients with AF on anticoagulation therapy. They may improve current risk stratification and have the potential to help guide therapeutic decisions in high-risk situations considering evolving therapeutic possibilities.

Hypotheses, Objectives and Aims: Hypotheses:Caspase-3, cleaved and activated, and dystrophin can be detected in human circulation. The levels of these two markers are elevated during acute myocardial infarction. Furthermore, the levels of these two proteins are greater in those who develop heart failure than those who do not. Objectives: * To determine whether cleaved caspase-3 and dystrophin can be detected in human circulation after an acute myocardial infarction * To compare serum levels of these two markers in those who develop heart failure and those who do not Scientific Background and Significance: Apoptosis is a regulated biological process resulting in cell death (4-9). Caspases, a family of cysteine acid proteases regulate the process, and in fact, lead to apoptosis. Apoptotic trigger or signal results in the activation of proximal or initiator caspases (such caspase-8, -9, 10). These initiator caspases then cleave and in turn activate downstream effector caspases such as caspases-3, -6 and -7. These effector caspases then cleave various proteins such as those present in cytoskeletons and nucleus like lamin A, alpha-fodrin and poly (ADP-ribose) polymerase, leading to apoptosis. Caspase-3 is the key executioner in this apoptotic pathway, responsible totally or critically in the proteolytic cleavage of cellular and nuclear proteins. Activation of caspase-3 requires proteolytic processing of its inactive zymogen into active p17 and p12 fragments. The cleaved caspase-3 can be detected by antibodies specific for this cleaved enzyme (p17 fragment) in cell lysates by immunoblotting or by an ELISA assay utilizing spectrophotometric determination with a microplate reader at OD450 nm. Ischemia and reperfusion are known to cause apoptosis. Therefore, acute MI may be associated with release of the final executioner of apoptosis that is caspase-3, into the circulation.Another potential marker for acute deterioration is dystrophin. Dystrophin was originally identified as the x-linked gene whose mutations in its N-terminus cause cardiomyopathy. Dystrophin provides important structural support for the cardiac myocyte and its sarcolemmal membrane (10-11). It links actin at its N-terminus with the dystrophin-associated protein complex and sarcolemma at the C-terminus and the extracellular matrix of muscle. Mutations cause loss of support and sarcolemmal instability and myopathy. Myocardial dystrophin translocation and cleavage are associated with the progression of heart failure and contractile dysfunction. These changes are reversed following reduction of mechanical stress from ventricular assistance device (12). Since MI is associated with sarcolemmal instability, dystrophin may also be released into circulation.

The involved professions and the patient representatives unanimously recommend as primary endpoint for this study the proposed disease specific outcome measure: symptom relief measured on a VAS and PGI-I scale. This clinical outcome parameter can be reliable assessed within 6 months after the CA release (1, 9, 10). A two years follow up is suggested to extinguish the positive effect of attention in the diagnostic phase (11). This study design allows for patient and observer blinding and for the sham group the eCAR approach is still feasible if the CARoSO outcome support this without applying additional scar tissue. A sham operation without skin incisions results in unblinding for the patient and the observer and thus undermines the basis of the evidential value of this study. There are no known cases where irreversible damage such as the intestinal infarction has occurred due to not treating this condition. Possible risks of not treating are continuous (pain) complaints and weight loss. The patients who undergo the sham operation and who still have complaints after unblinding of the study and proven effectivity of eCAR can still undergo the endoscopic AC release.

The first Intestinal Vascular Emergency Unit (SURVI), with the institutional support of AP-HP, opened on 4 January 2016, within the Paris-Nord Val de Seine University Hospital Group. This intensive care is dedicated to the management of mesenteric ischemias (acute mesenteric ischemias, chronic mesenteric ischemias) and Intestinal Vascular Diseases Without Ischemia. The organisation of this type of dedicated centre, combining advances in resuscitation, interventional radiology and knowledge of intestinal vascular diseases, has led to a radical change in the prognosis for acute mesenteric ischaemia with a survival rate of over 80% and an intestinal resection rate of less than 40%. Acute mesenteric ischaemia (AMI) is characterised by the combination of digestive distress and vascular insufficiency: occlusive (thrombosis, embolism, arterial, venous) or non-occlusive (low flow or vasospasm). The vital prognosis is catastrophic in the absence of treatment (the mortality rate of an intestinal infarction is almost 100% without treatment), and the functional and anatomical after-effects are major for the survivors. Many intestinal vascular diseases have been identified as providing acute and chronic mesenteric ischaemia. The nosological framework of these diseases is broad, ranging from constitutional diseases of the vessels (collagenosis, arcuate ligament syndrome) to acquired diseases of a thrombophilic, cardiac, degenerative, autoimmune, iatrogenic, traumatic nature... The rarity of these diseases (with the exception of atherosclerotic disease, the incidence of which is increasing with the ageing of the population) makes their level of knowledge insufficient. The natural history of vascular diseases without ischaemia (rate of acute and chronic mesenteric ischaemia, mortality rate, resection rate...) is currently not described. The construction of a longitudinal observational cohort is necessary for the prevalence of ischaemic complications and predictive factors.

Chronic mesenteric ischemia (CMI) is often caused by narrowings in the arteries providing blood to the intestines. Endovascular stent placement is considered the preferred treatment for this condition. Guidelines increasingly support the use of so called covered stents (CS) in stead of bare stents (BMS) for this use but the level of evidence for this is limited. Using CS incur additional costs for healthcare short-term but may prevent recurrence of narrowing and symptoms postoperatively benefitting patients and healthcare. Study Objective: To evaluate the outcomes after stenting of mesenteric arteries using BMS or CS. Study Outcome: Primary stent patency 1 year after placement The trial will also evaluate complications, how often stents need to be reoperated, Quality of Life (QoL) and reasons for subjects death Method: This is a so called prospective, randomized controlled trial comparing CS vs. BMS. This means that one patients have agrred to treatment they will be randomly selected for treatment with either CS or BMS . The stent metal structure is identical in the two implants and the only difference is the graft covering, making this study unique. The study will also collect blood samples for a biobank that will be used to study markers of disease and how these effect treatment outcomes. All patients referred to the Department of Vascular Surgery due to CMI are considered for inclusion if they havechronic symptoms consistent with CMI, significant stenosis or occlusion of the superior mesenteric artery and are \> 18 years Subjects not able to provide informed consent or who have non atherosclerotic cause of CMI, signs of acute loss of blood flow to the intestines cannot participate. Previous stent treatment in the superior mesenteric artery, pregnancy, allergies to contrast or stent materials are also reasons for not being included in this trial. Side effects, risks and disadvantages for participants The risk for procedure-related complications is less than 5% and similar in both study groups. Most short-term complications are related to vascular access sites and consist of local bleeding and thrombosis. Other potential complications include impaired renal function due to contrast use, contrast allergy, arterial dissection and death.

This study aims to address the challenges of enteral nutrition support in critically ill ICU patients with varying gastrointestinal function. We'll use bedside Doppler ultrasound to monitor superior mesenteric artery (SMA) blood flow changes post - feeding, exploring its correlation with Acute Gastrointestinal Injury (AGI) and other hemodynamic indicators. Our goals are to identify the patterns of SMA blood flow changes, establish a predictive model linking SMA blood flow reactivity to AGI risk, and propose individualized enteral nutrition strategies based on intestinal hemodynamics. Through this innovative approach, we hope to enhance the safety of enteral nutrition, reduce AGI incidence, and improve patient outcomes.

This is an open, prospective, interventional, single-center clinical investigation designed to examine the feasibility and safety of the IscAlert™ device in patients scheduled for reconstructive flap surgery. 56 will be enrolled to undergo the procedures using a total of 350 devices depending on the injuries. IscAlert is 0.8 mm in diameter and in vitro testing, shows stable and accurate measurements of pCO2. More than 200 animal experiments have been done with the sensor. The experiments have shown that the sensor detects ischemia (Increased CO2-measurements) in real time in the following organs and tissues: Brain, heart, liver, kidneys, pancreas, intestines, musculature and subcutaneous tissue. Sensitivity and specificity are close to 100%. The sensors are inserted into tissue by a split needle technique. The split needle is the size of a 3-gauge peripheral venous catheter. In animal studies, no complications have been detected when using the sensor. The IscAlert sensors are connected to an electronics unit that is fixed to the skin with an adhesive plaster or glue outside the sterile area. The electrical signals are redirected to a PC approved for clinical use which continuously records tissue pressures of CO2. IscAlert is inserted into normal muscle and/or subcutaneous tissue distal on the reconstructed flap to be operated at the end of surgery. The insertion is far away from the operating field. The insertion is done under sterile conditions in accordance with standard sterility criteria at the hospital. No pain during insertion will occur because of insertion is performed during general anesthesia. Also, the insertion can be compared to an intramuscular injection. Postoperatively, the IscAlert sensor will continuously monitoring tissue CO2 and temperature. If ischemia occur, for examples caused by a thrombus, an increase in tissue CO2 and a lower temperature will evolve. This will be detected by the sensor which will alarm the investigators. This will lead to assessment of the reconstructed flap and if restricted blood flow is diagnosed, a reoperation or other intervention will be performed. The IscAlert will be removed from the patient before the patient is discharged from the hospital or a maximum of 10 days (the event that occurs first). Approximately 360 devices are planned to be used in this clinical study. One of the sensors will be used as a control inserted into neighboring tissue. The primary objective is to compare CO2-levels in the reconstructed flap in individuals who has undergone reconstructed flap surgery and investigate if CO2-level is different in patient diagnosed with obstructed blood flow vs. patients with sufficient blood flow in the reconstructed flap. Our hypotheses are: 1. The IscAlert™ device will be able to detect the presence of ischemia in the reconstructed flap by increased pCO2 levels and decrease in tissue temperature, measured by IscAlert™. 2. By using the IscAlert™ device monitoring ischemic events, an early treatment for ischemia could lead to higher incidence of reconstructed flap survival rates, and less revision surgery caused by thrombosis. 3. No clinically significant bleeding or infection will occur using IscAlert™ in this clinical study.

This is an open, prospective, interventional, single-center clinical investigation designed to examine the feasibility and safety of the IscAlert™ device in patients scheduled for extremity replant surgery. Sixty patients will be enrolled to undergo the procedures using a total of 400 devices depending on the injuries. IscAlert is 0.8 mm in diameter and in vitro testing, shows stable and accurate measurements of pCO2. More than 200 animal experiments have been done with the sensor. The experiments have shown that the sensor detects ischemia (Increased CO2-measurements) in real time in the following organs and tissues: Brain, heart, liver, kidneys, pancreas, intestines, musculature and subcutaneous tissue. Sensitivity and specificity are close to 100%. The sensors are inserted into tissue by a split needle technique. The split needle is the size of a 3-gauge peripheral venous catheter. In animal studies, no complications have been detected when using the sensor. The IscAlert catheters are connected to an electronics unit that is fixed to the skin with an adhesive plaster or glue outside the sterile area. The electrical signals are redirected to a PC approved for clinical use which continuously records tissue pressures of CO2. IscAlert is inserted into normal muscle and/or subcutaneous tissue distal on the replanted limb to be operated at the end of surgery or immediate postoperatively. The insertion is far away from the operating field. The insertion is done under sterile conditions in accordance with standard sterility criteria at the hospital. No pain during insertion will occur because of insertion is performed during anesthesia (general or regional). Also, the insertion can be compared to an intramuscular injection. Postoperatively, the IscAlert sensor will continuously monitoring tissue CO2 and temperature. If ischemia occur, for examples caused by a thrombus, an increase in tissue CO2 and a lower temperature will evolve. This will be detected by the sensor which will alarm the investigators. This will lead to assessment of the replanted extremity and if restricted blood flow is diagnosed or suspected, a reoperation will be performed. Sixty patients will be enrolled to undergo the procedures. The IscAlert will be removed from the patient before the patient is discharged from the hospital or a maximum of 10 days (the event that occurs first). Approximately 500 devices in 80 injured extremities is planned to be used in this clinical study. The primary objective is to compare CO2-levels in the replanted extremity in individuals who has undergone extremity replantation surgery and investigate if CO2-level is different in patient diagnosed with obstructed blood flow vs. patients with sufficient blood flow in the replanted extremity. Our hypotheses are: 1. The IscAlert™ device will be able to detect the presence of ischemia in the extremity replant by increased pCO2 levels and decrease in tissue temperature, measured by IscAlert™. 2. By using the IscAlert™ device monitoring ischemic events, an early treatment for ischemia could lead to higher incidence of replantation survival rates, and less revision surgery caused by replantation thrombosis. 3. No clinically significant bleeding or infection will occur using IscAlert™ in this clinical study.

The primary objective of this open-label pilot study is to investigate whether an endoscopically placed lumen apposing metal stent is an effective alternative to surgery in patients that have a clear indication for reversal of their gastric bypass.

This is a prospective registry of patients with chest pain, chest discomfort, breathlessness who do not have a blockage in their heart artery. This condition is known as angina/ischemia and non-obstructive coronary arteries (ANOCA/INOCA). The purpose of this registry is to help us understand the prevalence, causes of these conditions, identify effective diagnostic strategy, and long term outcome in this patient population. Patients will undergo comprehensive invasive evaluation including coronary angiography, intravascular imaging, and physiologic measurements as a standard of care. Details regarding the participant's angiogram, endothelial function testing, microvascular testing, intravascular ultrasound, and myocardial bridge testing, if performed, will be entered into a research database. Participants may be contacted by email or phone periodically for follow-up information, such as surveys, an update on medical history, and/or a check on their medical status or symptoms. We anticipate gathering these data at 6 months, 1 year, 3 years, 5 years, and 10 years, and every 5 years thereafter following their enrollment. The overall objective of this registry study is to identify specific endotypes of ANOCA by invasive evaluation and study long term outcome. Specific goals include: 1. Describe the prevalence of the following ANOCA endotypes: endothelial dysfunction, microvascular dysfunction, vasospastic angina, myocardial bridging (MB), and other disorders of coronary physiology, and non-cardiac chest pain; 2. Characterize the natural history and outcomes of patients with ANOCA and determine variables associated with major adverse cardiovascular events