Active clinical trials for "Aneurysm"

Abdominal aortic aneurysm (AAA) is a common vascular disease and associated with risk of rupture, but also with a high cardiovascular (CV) event rate. A key difficulty in AAA is predicting these life-threatening complications, which are strongly linked to vascular health. In 2013, the SMART risk score was developed to calculate the risk of the patients for recurrent vascular events based on clinical characteristics. Recently, a novel, easy to perform, non-invasive test of endothelial function (the carotid artery reactivity (CAR) test), reflecting target organ damage, has been introduced. The CAR is a simple, quick (5-min), non-invasive test that uses ultrasound to examine the carotid artery in response to sympathetic stimulation by placing one hand in cold water. This test shows strong agreement with both coronary and aortic responses to sympathetic stimulation and predicted CV-events in patients with peripheral arterial disease. The aim of this prospective 2-year follow-up study is to investigate the predictive capacity of the CAR-test for development of CV-events after elective AAA repair in comparison to the SMART risk score. Secondary objectives are to investigate the predictive capacity of arterial stiffness measurements and the post-operative CAR-test for development of CV-events and to evaluate health status scores to provide insight if these scores can support clinical decision making.

Abdominal aortic aneurysm (AAA) is an abnormal dilatation of the aorta in the abdomen due to a wall weakening caused by atherosclerosis. While indications for a rupture intervention are based on AAA maximal diameter (MaxD) (5 cm), 23% of ruptured AAAs are less than 5 cm and in large AAAs, rupture rate could be lower than expected. We propose to expand and validate our vascular ultrasound elastography software to 3D. Strain maps generated from radiofrequency (RF) data acquired from 30 AAA patients with a matrix-array 3D probe will be registered to conventional CT (phase 1) and validated to a biomechanical for characterization of AAA wall, assessing vulnerability and influence of surrounding tissues (phase 2). At the end of the project, we will have analyzed 3D strain maps to improve patient selection before surgery.

This registry study will investigate the incidence of and outcomes associated with clopidogrel hyper-responsive patients treated at Methodist Dallas Medical Center, beginning in January 2018, who suffered cerebral aneurysms.

The purpose of this research study is to evaluate the ability of laser speckle contrast imaging to visualize blood flow in real time during neurosurgery. Real-time blood flow visualization during surgery could help neurosurgeons better understand the consequences of vascular occlusion events during surgery, recognize potential adverse complications, and thus prompt timely intervention to reduce the risk of stroke. The current standard for visualizing cerebral blood flow during surgery is indocyanine green angiography (ICGA), which involves administering a bolus of fluorescent dye intravenously and imaging the wash-in of the dye to determine which vessels are perfused. Unfortunately, ICGA can only be used a few times during a surgery due to the need to inject a fluorescent dye, and provides only an instantaneous view of perfusion rather than a continuous view. Laser speckle contrast imaging does not require any dyes or tissue contact and has the potential to provide complementary information to ICGA. In this study we plant to collect blood flow images with laser speckle contrast imaging and to compare the images with ICGA that is performed as part of routine care during neurovascular surgical procedures such as aneurysm clipping.

This project concerns a population at risk of sudden death by dissection of the thoracic aorta. Its interest is to make it possible to recognize the genes that protect or worsen the evolution of aneurysms, to better understand the mechanisms involved, to detect and treat aneurysms of the thoracic aorta, wich is a pathology that is completely silent clinically until life-threatening complications. The variability in the severity of the disease within the same family is related to modifier genes. The objective is to find the modifying factors that account for the variability in the severity of the progression of aneurysms of the thoracic aorta.

To conduct a retrospective multicenter cohort study to define benchmark values for best achievable outcomes following microsurgical clipping of unruptured intracranial aneurysms (UIA).

The goal of this prospective observational cohort study is to compare health related quality of life in patients with abdominal aortic aneurysms treated by either standard or complex EVAR (endovascular aneurysm repair) devices. The main question it aims to answer are: Compare differences between the physical scores from the preoperative to the postoperative settings between patients treated with standard EVAR vs non-stnadard endovascular aortic repair (F-/BEVAR) To compare long-term physical scores postoperatively between patients treated with standard EVAR vs non-standard endovascular aortic repair (F-/BEVAR) at one year. To explore at which time points (if ever) patients treated with standard-EVAR and nonstandard endovascular aortic repair (F-/BEVAR) have restored or normalized physical scores measured by SF-12, measured at 30 days, 6 months, 1 and 3 years. Participants will be asked to fill out forms pre- and postoperatively with regards to health related quality of life. The different groups for comparison will be either standard EVAR for infrarenal aortic aneurysms or complex EVAR (fenestrated or branched) for paravisceral aortic aneurysms (PVAAA).

Intracranial aneurysm rupture is a leading cause of hemorrhagic strokes which carry high mortality and disability rates as well as high healthcare costs. Unruptured intracranial aneurysms (UIA) are common in the general population, occurring in 1-2% of individuals. Previous studies have shown that UIA growth and rupture are strongly associated with each other, with growing aneurysms 9-12 times more likely to rupture, and nearly all aneurysms growing prior to rupture. Thanks to advanced medical imaging, UIA are now more and more often detected incidentally. However not all aneurysms qualify for preventive surgical or interventional procedures according to current International Study of Unruptured Intracranial Aneurysms (ISUIA) guidelines, and some must therefore be monitored for growth. Current guidelines are based heavily on size, an inconsistent predictor of future growth. To improve management strategies for individual patients and more comprehensively assess aneurysm risk, the investigators propose to identify risk factors related to growth. Aneurysm etiology is multifactorial, with both genetic and environmental contributions to aneurysm formation, growth, and rupture. Exploring new risk factors based on aneurysm natural history and understanding the mechanisms underlying aneurysm rupture have been extensive research areas. As previous studies have shown that quantitative imaging biomarkers (QIB) can provide a more accurate assessment of the characteristics of aneurysms, the investigators propose a combined study which identifies QIB associated with aneurysm growth to identify factors related to growth.

An aortic aneurysm (thoracic or abdominal) is a permanent dilatation of the aorta caused by weakening in the arterial wall. The feared complication is aortic rupture or dissection, leading to potentially lethal aortic bleeding and associated with mortality rates up to 95%. The current diagnosis criteria do not suffice, therefore the goal of this study is the development of an improved biomechanics-based and microstructural-based diagnostic tool.

During open surgery of a thoraco-abdominal aortic aneurysma (TAAA), diminished blood flow to the myelum can result in hypoxia, compromising proper function of the spinal cord. Intraoperatively, motor evoked potentials (MEP) are elicited to measure the functional integrity of the spinal cord. MEPs have proven to be a reliable marker of spinal cord ischemia. Moreover, these potentials react within minutes, which facilitates interventions to restore the blood flow. Monitoring intraoperatively with this ancillary test has reduced the rate of paraparesis to < 5%. Unfortunately, in the early postoperative period, spinal cord vulnerability is high. Therefore, some patients develop paraparesis, not during the surgical procedure, but after the surgical procedure. Postoperatively, suboptimal blood flow may lead to critical loss of function. This inadequate perfusion results in "delayed paraparesis". In the postoperative patient, it is not possible to measure MEPs when sedation is decreased, due to the high intensity of the electrical stimulus, which is unacceptably painful in the unanesthetized or partially anesthetized patient. Therefore ancillary tests are needed which can detect spinal cord ischemia postoperatively early, thus preceding the phase with clinically overt paraparesis. The test should be reliable and easy to perform for an extended period of time (up to several days). The purpose of this study is to explore the usefulness of various neurophysiological tests regarding accuracy and feasibility for the detection of spinal cord ischemia. In particular, to find a diagnostic test which is acceptable for the unanesthetized or partially anesthetized patient and therefore can also be performed postoperatively. These tests will be examined in fully sedated as well as partially sedated patients. The following candidate tests will be examined: Long loop reflexes (LLR) consisting of F-waves. Oxygenation measurements of the paraspinal muscles using Near-infrared spectroscopy (NIRS).