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《Mayo Clinic proceedings. Mayo Clinic》2022,97(8):1525-1533
The importance of the left atrial appendage (LAA) as the source of thromboembolism including stroke in patients with nonvalvular atrial fibrillation is well documented, with more than 90% of ischemic strokes related to a LAA thrombus. Although oral anticoagulation has been the standard of care, approximately 50% to 60% of patients either have contraindications to oral anticoagulation or do not continue the medication beyond the first year. This led to the development of local site-specific therapy to occlude the LAA by either surgical or transcatheter means. Despite marked advancements, incomplete LAA closure with surgical and transcatheter approaches remains frequent. The etiology of incomplete LAA closure and its clinical implications remain unclear. Multiple strategies are in development including changes in deployment techniques, a new device design, and alternative approaches to leak closure. 相似文献
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Elin Rosen-Wetterholm Oscar Cavefors Björn Redfors Sven-Erik Ricksten Elmir Omerovic Christian L. Polte Jonatan Oras 《Acta anaesthesiologica Scandinavica》2023,67(6):746-754
Introduction
Left ventricular (LV) dysfunction is estimated to occur in 10%–25% of the general intensive care unit (ICU) population and is frequently seen as regional wall motion abnormalities (RWMAs). Although RWMA is mostly attributed to myocardial ischemia or infarction, some studies have suggested that nonischemic RWMA might also be prevalent. We sought to establish that RWMA can be seen in critically ill patients with normal coronary arteries and to explore reasons for RWMA in this population.Methods
In this retrospective study, data from the hospital angiography register and the ICU register were collated between 2012 and 2019. Patients were identified who underwent angiography in conjunction with their ICU stay and had RWMA on echocardiography. Patients were divided into either those with non-obstructed or those with obstructed coronary arteries. Cardiac magnetic resonance imaging (cMRI) examinations were reviewed if they had been performed on patients with non-obstructed coronaries.Results
We identified 53 patients with RWMA and non-obstructed coronary arteries and 204 patients with RWMA and obstructed coronary arteries. Patients with non-obstructed coronary arteries were more often female, younger, and had fewer cardiovascular risk factors. They less commonly had ST elevation, but more frequently had T-wave inversion or serious arrhythmias. Troponin levels were higher in patients with obstructed coronary arteries, but NT-proBNP was similar between the groups. There were no differences in risk-adjusted 90-day mortality between patients with non-obstructed versus obstructed coronary arteries (OR 1.21, [95% CI 0.56–2.64], p = .628). In those with non-obstructed coronary arteries, follow-up echocardiography was available for 38 patients, of whom 30 showed normalization of cardiac function. Of the 14 patients with non-obstructed coronary arteries on whom cMRI was performed, 7 had a tentative diagnosis of Takotsubo syndrome or myocardial stunning; 4 had a myocardial infarction (preexisting in 3 cases); 1 patient had acute myocarditis; 1 patient had post-myocarditis; and 1 patient was diagnosed with dilated cardiomyopathy.Conclusion
RWMA can be seen to occur in critically ill patients in the absence of coronary artery obstruction. Several conditions can cause regional hypokinesia, and cMRI is useful to evaluate the underlying etiology. 相似文献6.
目的探讨术前彩色多普勒超声引导下应用亚甲蓝定位肿瘤边界在乳腺癌保乳手术中的效果。方法收集2015年5月至2017年12月拟行保乳手术的乳腺癌患者120例,随机分为观察组和对照组各60例。观察组术前在彩色多普勒超声引导下行亚甲蓝定位,对照组采用传统手术方法。所有标本切除后进行病理检查,统计两组切缘情况。从精准性及微创性两方面比较两种方法的手术效果。结果观察组中,3例(5.0%)最大切缘>2 cm,57例(95.0%)最大切缘≤2 cm;对照组中,31例(51.7%)最大切缘>2 cm,29例(48.3%)最大切缘≤2 cm。两组比较差异有统计学意义(P=0.000)。观察组6例(10.0%)患者的手术标本镜下切缘阳性,54例(90.0%)切缘阴性;对照组15例(25.0%)镜下切缘阳性,45例(75.0%)切缘阴性。两组比较差异有统计学意义(P=0.031)。观察组和对照组分别有2例和3例在行二次扩切后切缘仍为阳性,改行乳腺全切手术。结论采用术前彩色多普勒超声引导下亚甲蓝定位肿瘤边界指导乳腺癌保乳手术的方法较常规方法在手术精准性及微创性两方面均有优势。 相似文献
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Joakim Nordanstig Odd Bech-Hanssen Per Skoog Lennart Jivegård 《Scandinavian cardiovascular journal : SCJ》2019,53(3):153-161
Objective. Skeletal muscle perfusion during walking relies on complex interactions between cardiac activity and vascular control mechanisms, why cardiac dysfunction may contribute to intermittent claudication (IC) symptoms. The study aims were to describe cardiac function at rest and during stress in consecutive IC patients, to explore the relations between cardiac function parameters and treadmill performance, and to test the hypothesis that clinically silent myocardial ischemia during stress may contribute to IC limb symptomatology. Design. Patients with mild to severe IC (n?=?111, mean age 67 y, 52% females, mean treadmill distance 195 m) underwent standard echocardiography, dobutamine stress echocardiography (SE) and treadmill testing. The patient cohort was separated in two groups based on treadmill performance (HIGH and LOW performance). Results. Ten patients (9%) had regional wall motion abnormalities of which three had left ventricular ejection fraction <50% at standard echocardiography. A majority had lower than expected systolic- and diastolic ventricular volumes. LOW performers had smaller diastolic left ventricular volumes and lower global peak systolic velocity during dobutamine stress. No patient demonstrated significant cardiac dysfunction during dobutamine provocation that was not also evident at standard echocardiography. Conclusions. Most IC patients were without signs of ischemic heart disease or cardiac failure. The majority had small left ventricular volumes. The hypothesis that clinically silent myocardial ischemia impairing left ventricular function during stress may contribute to IC limb symptomatology was not supported.Trial registration: ClinicalTrials.gov identifier: NCT01219842. 相似文献
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