Screening for Abdominal Aortic Aneurysm Using a Portable Transthoracic Echocardiography Among Patients...
Acute Coronary SyndromeThe prevalence of Abdominal Aortic Aneurysm among 65 years old individuals worldwide is 1-2%. when diagnosis is confirmed by abdominal Ultrasound the prevalence is 5.5% in men and 1% in women. As abdominal aortic aneurysm and coronary heart disease share common risk factors, patients with acute coronary syndrome represent a high risk population in which screening for another atherosclerotic site is recommended. Patients admitted for ACS undergo routinely TTE. during the same study, TTE may offer the opportunity to evaluate the cardiac morphology and function and to screen for Abdominal Aortic aneurysm. It was reported by different studies that the Sensitivity of this technique was between 91-96% for AAA screening. In addition, this method is cheap, available and requires only 2-3 minutes to be added to the standard TTE. we plan to examine patients admitted with ACS in our Intensive Care Unit for screening AAA by TTE in subcostal views in addition to the standard TTE examination.
Open Versus Endovascular Repair of Abdominal Aortic Aneurysms
Abdominal Aortic Aneurysm Without RuptureThis is an observational retrospective cohort study of all patients consecutively submitted to elective abdominal aortic aneurysm surgery repair at a tertiary referral centre between 2009 and 2015. Patients were excluded if they were non-elective cases or had complex aortic aneurysms (juxta-renal, thoraco-abdominal or thoracic). Differences between both groups of repair were assessed, as well as short- and long-term complications including medical complications, duration of hospital stay, major cardiovascular events, mortality and vascular reintervention.
Overlay of 3D Scans on Live Fluoroscopy for Endovascular Procedures in the Hybrid OR
Abdominal Aortic Aneurysm (AAA)Thoracic Aortic Aneurysm (TAA)2 moreAs endovascular procedures become more complex, there is a growing need for 3D image overlay to assist with device guidance and placement. Currently, a 3D image is typically created intra-operatively using 3D rotational angiography (3D-RA) or cone-beam CT (XperCT). This 3D image may then be overlaid on live fluoroscopy to provide 3D guidance information (Dynamic 3D Roadmapping). Philips Healthcare multimodality overlay products allows registration of a pre-acquired MR/CT or 3D rotational image to live fluoroscopy.
Aortic Distensibility
Abdominal Aortic AneurysmCan software be developed to automatically aid in the measurement of abdominal aortic aneurysms, and is there a way to predict future rupture or growth of abdominal aortic aneurysms.
Automatic Abdominal Aortic Aneurysm Diameter Measurement
AAA - Abdominal Aortic AneurysmManaging abdominal aortic aneurysms currently relies on diameter assessment with ultrasound. Diameter reproducibility with two-dimensional ultrasound is challenging, and requires experienced operators. A novel automatic three-dimensional ultrasound system has the potential to facilitate more precise diameter measurements than two-dimensional ultrasound. This study aimed to assess the variance of abdominal aortic aneurysm diameter measurements among ultrasound novices and experts by comparing two-dimensional ultrasound with the three-dimensional ultrasound system in a clinical setting. Ten patients under abdominal aortic aneurysm surveillance were examined by 29 ultrasound-operators: 13 experts and 16 novices. The experts were sonographers and physicians highly experienced in abdominal aortic aneurysm ultrasound, and the novices were medical students and junior residents with sparse ultrasound experience.
Fusion of CT Angiography With 3D Contrast Ultrasound as a Method for Follow up for Endovascular...
Abdominal Aortic AneurysmEndoleakAbdominal Aortic Aneurysm (AAA) is a known vascular entity that may be life threatening condition .The most common treatment approach nowadays is the endovascular approach, a procedure known as endovascular aortic repair (EVAR). The most common procedure related complication is the expansion of the aneurysm from a "feeding vessel", usually a lumbar or intercostal artery. Another known complication is an endoleak from the stentgraft.Today, accepted EVAR follow up protocol consists of one multiple multiphasic CT angiography (CTA) scan, one month after the procedure and ultrasound exams there after . Ultrasonography is a useful method for detection and evaluation of AAA, has no ionizing radiation and is useful for the dynamic estimation of the aortic width in patients post EVAR. However, the sensitivity of ultrasonography solely for detection of endoleaks in post EVAR patients is not high.In recent years, the development of "fusion" applications allows the dual modality merge between ultrasound and CT scans that can be used as follow up examinations of known imaging findings on CT .Another application that had been developed for ultrasound machines is the ability to generate a 3 dimensional (3D) reconstruction which allows more precision. In the recent year the usage of intravenous contrast agent for ultrasonography based on microbubbles (BRACO SONOVIEW) has been approved by the Israeli ministry of health. This contrast agent is not nephrotoxic and the risk for allergic reaction is very low statistically similar to Gadolinium.A 3D contrast enhanced ultrasonography "fused" together with CTA may be a helpfull addition , which lacks radiation and odine contrast reactions and nephrotoxicity ,in the follow up in post EVAR patients , by means of identifing endoleaks at an earlier stage than by ultrasound alone. The purpose of our research is to evaluate the combined modality (fusion of CTA with CEUS) mentioned above in identifing early endoleaks in post EVAR patients and thus enabilng early intervention when needed
Ultrasound Velocimetry in the Abdominal Aorta Before and After Endovascular Aneurysm Repair
Abdominal Aortic AneurysmRationale: An abdominal aortic aneurysm (AAA) is a common vascular disease with a high mortality in case of rupture. The underlying processes initiating aneurysmal degeneration and driving aneurysmal growth remain poorly understood. Local hemodynamics might play a key role in the pathogenesis of AAA, as it is associated with aneurysmal growth, intraluminal thrombus formation and rupture risk. Visualizing and quantifying local blood flow profiles could eventually provide more insight in the underlying mechanisms of aneurysm progression as well as identify smaller AAA with increased vulnerability or larger AAA with low risk of rupture. Consequently, this may improve risk assessment and provide patient-specific therapy guidance. Nowadays, endovascular aneurysm repair (EVAR) is the preferred treatment modality in most patients with an infrarenal AAA. However, EVAR is associated with a relatively high reintervention rate. It is hypothesized that the placement of a stent graft may alter local hemodynamics and subsequent recirculations or flow stagnations promote the onset of thrombosis or micro-emboli. These unfavourable flow conditions might be related to various complications after EVAR, such as limb occlusion, renal dysfunction, and the persistence of type II endoleaks. Visualizing local blood flow profiles after EVAR might provide insight in these (un)favourable conditions. In vivo blood flow quantification is a great challenge, particularly in the abdomen. Advanced ultrasound based techniques, incorporating ultrasound contrast agents and plane wave imaging, proved to be feasible in quantifying aortoiliac blood flow patterns in healthy volunteers. Objective: The aim of this study is to determine the feasibility of ultrafast contrast-enhanced ultrasound particle image velocimetry (echoPIV) measurements to quantify spatiotemporal blood flow velocity profiles in the abdominal aorta of AAA patients before and after endovascular repair. Secondary objectives are to determine the correlation between echoPIV and phase-contrast MRI (PC MRI) based measurements to ultimately validate the spatiotemporal velocity profiles obtained with echoPIV. Furthermore, changes in blood flow velocity profiles after placement of a stent graft will be evaluated.
Secondary Intervention and Surveillance After EVAR
Abdominal Aortic Aneurysm Without RuptureThis is a retrospective cohort study of consecutive patients submitted to elective EVAR, between February/2009 and May/2019 in a single institution. Symptomatic or ruptured AAA, mycotic aneurysms, isolated iliac aneurysms and complex abdominal aortic repairs were excluded. The primary outcomes were freedom from secondary intervention and compliance with follow-up, defined as surveillance imaging performed within a periodicity no longer than 18 months.
Contrast Enhanced Ultrasound, Endoleak Detection Following EVAR v1.3
EndoleakAbdominal Aortic AneurysmA single site cross-sectional comparison of paired diagnostic imaging modalities. This study will show the sensitivity and specificity of CEUS in detecting the various types of endoleaks, in comparison to tCTA, following EVAR. It will collect data to allow comparison of diagnostic accuracy across modalities including CDU, CEUS and tCTA. It will collect time taken to perform the various types of scan, to allow healthcare costs to be calculated for each imaging modality.
Measurement of Maximum Diameter of Native Abdominal Aortic Aneurysm by Angio-CT
Abdominal Aortic AneurysmScreening for an abdominal aortic aneurysm, monitoring its growth and evaluation of its risk of rupture are based on the measure of its maximum diameter. The abdominal aortic aneurysm's treatment to prevent its rupture is recommended from a threshold of 50-55 mm in men and of 45-50 mm in women. The importance of this measure for patient management justify a specific and homogeneous protocol of measure. However, the diversity of methods of measuring the maximum diameter with scanner and ultrasound was shown. The impact of various angio-CT based measures of maximum AAA diameter, and the impact of reproducibility limits on the decision to operate have never been investigated.