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Open in a separate window OBJECTIVESLung volume reduction (LVR) is an efficient and approved treatment for selected emphysema patients. There is some evidence that repeated LVR surgery (LVRS) might be beneficial, but there are no current data on LVRS after unsuccessful bronchoscopic LVR (BLVR) with endobronchial valves (EBVs). We hypothesize good outcome of LVRS after BLVR with valves.METHODSIn this study, we retrospectively investigated all patients who underwent LVRS between 2015 and 2019 at 2 centres after previous unsuccessful EBV treatment. They were further divided into subgroups with patients who never achieved the intended improvement after BLVR (primary failure) and patients whose benefit was fading over time due to the natural development of emphysema (secondary failure). Patients with severe air leak after BLVR and immediate concomitant LVRS and fistula closure thereafter were analysed separately.RESULTSA total of 38 patients were included. Of these, 19 patients had primary failure, 15 secondary failure and 4 were treated as an emergency due to severe air leak. At 3 months after LVRS, forced expiratory volume in 1 s had improved significantly by 12.5% (P = 0.011) and there was no 90-day mortality. Considering subgroups, patients with primary failure after BLVR seem to profit more than those with secondary failure. Patients with severe air leak after BLVR did not profit from fistula closure with concomitant LVRS.CONCLUSIONSLVRS after previous BLVR with EBVs can provide significant clinical improvement with low morbidity, although results might not be as good as after primary LVRS.  相似文献   
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Magnetic resonance imaging (MRI) has been frequently considered unsafe for patients with ferromagnetic implants: risks to be considered include induction of electric current, heating and dislocation of the prosthesis. Previous in vitro and in vivo studies have indicated the possibility of performing MRI examinations on patients with prosthetic heart valves. The aim of our study was to verify the presence of artifacts at the level of the prosthetic heart valve in vivo using a low-field MR unit (0.2 T) and to define the possibility of a functional analysis of the valve in patients with biomedical or mechanical prostheses. We evaluated 14 patients surgically treated for implantation of nine biological and seven mechanical aortic and mitral valves. A low-field MR unit (0.2 T) was employed using cine-MR technique on long- and short-axis view. The images were acquired on planes parallel and perpendicular to the valvular plane. Semiquantitative analysis with double-blind evaluation for definition of the extent of the artifact was performed. Three classes of artifacts were distinguished from minimal to significant. The examinations showed the presence of minimal artifacts in all biological heart valves and moderate artifacts in mechanical valves giving good qualitative data on blood flow near the valve. Analysis of the flow behind the valve showed signs of normal function in 13 prostheses and pathological findings in the remaining three. In these latter cases, MRI was able to define the presence of a pathologic aortic pressure gradient, mitral insufficiency and malpositioning of the mitral valve causing subvalvular turbulence. Nevertheless, we believe that the application of velocity-encoding cine-MR is more promising than semiquantitative analysis of artifacts.  相似文献   
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We presented a 77‐year‐old man with hypertrophic obstructive cardiomyopathy applied with flail tricuspid leaflet and severe tricuspid regurgitation leading to right heart failure 2 months after the failed septal ablation. The ruptured anterior tricuspid papillary muscle resulted from infarction of the base of anterior papillary muscle of the right ventricle (RV) confirmed by magnetic resonance imaging. As the septomarginal band is frequently lit up by intracoronary contrast that particular attention should be paid to the RV papillary muscles. And, if the papillary muscles or the RV free wall is brightened, then the use of that septal artery should be avoided.  相似文献   
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