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BackgroundSelection of the transcatheter heart valve size for a mitral valve-in-valve procedure is based on the type and manufacturer’s labelled size. However, accurate information of surgical heart valve (SHV) size may not be available in the patient’s medical record. The purpose of this study is to establish reference data for computed tomography (CT) dimensions of commonly used mitral SHV in order to determine the manufacturer’s labelled size from a cardiac CT data set.MethodsCT datasets of 105 patients with surgical mitral bioprosthesis and available manufacturer labeled datasets were included in the analysis. CT derived valve dimensions were assessed by two observers using multiplanar reformats aligned with the basal sewing ring. A circular region of interest was used in a standardized fashion to minimize influence of image acquisition and reconstruction parameters. Interobserver variability was assessed by Bland-Altman analysis.ResultsThe CT-derived dimensions were stratified by valve size and type, and SHV properties were demonstrated for 5 common valve types. Variability of measurements was small and inter-observer limits of agreement were narrow. Stratified by SHV type, no overlap was noted for CT-derived dimensions among different SHV sizes . A reference table of CT characteristics of surgical mitral bioprosthesis types was created.ConclusionThe study provides reference CT data for determining the manufacturers’ labeled SHV size across a range of commonly used mitral SHVs. The findings will be important to help identify types of surgical mitral bioprosthesis utilizing CT characteristics for patients without SHV size documentation.  相似文献   
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ObjectivesGuidelines suggest aortic valve replacement (AVR) for low-risk asymptomatic patients. Indications for transcatheter AVR now include low-risk patients, making it imperative to understand state-of-the-art surgical AVR (SAVR) in this population. Therefore, we compared SAVR outcomes in low-risk patients with those expected from Society of Thoracic Surgeons (STS) models and assessed their intermediate-term survival.MethodsFrom January 2005 to January 2017, 3493 isolated SAVRs were performed in 3474 patients with STS predicted risk of mortality <4%. Observed operative mortality and composite major morbidity or mortality were compared with STS-expected outcomes according to calendar year of surgery. Logistic regression analysis was used to identify risk factors for these outcomes. Patients were followed for time-related mortality.ResultsWith 15 observed operative deaths (0.43%) compared with 55 expected (1.6%), the observed:expected ratio was 0.27 for mortality (95% confidence interval [CI], 0.14-0.42), stroke 0.65 (95% CI, 0.41-0.89), and reoperation 0.50 (95% CI, 0.42-0.60). Major morbidity or mortality steadily declined, with probabilities of 8.6%, 6.7%, and 5.2% in 2006, 2011, and 2016, respectively, while STS-expected risk remained at approximately 12%. Mitral valve regurgitation, ventricular hypertrophy, pulmonary, renal, and hepatic failure, coronary artery disease, and earlier surgery date were residual risk factors. Survival was 98%, 91%, and 82% at 1, 5, and 9 years, respectively, superior to that predicted for the US age-race-sex–matched population.ConclusionsSTS risk models overestimate contemporary SAVR risk at a high-volume center, supporting efforts to create a more agile quality assessment program. SAVR in low-risk patients provides durable survival benefit, supporting early surgery and providing a benchmark for transcatheter AVR.  相似文献   
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AimsThis review aims to provide an update of available methods for imaging calcification activity and potential therapeutic options.Data SynthesisAortic valve calcification represents the most common heart valve condition requiring treatment among adults in Western societies. No medical therapies are proven to be effective in treating symptoms or reducing disease progression. Therefore, surgical or transcatheter aortic valve replacement remains the only available treatment option. Elevated circulating concentrations of lipoprotein(a) is strongly associated with degenerative aortic stenosis. This relationship was first observed in prospective observational studies, and the causal relationship was confirmed in genetic studies.ConclusionsNew therapeutic targets have been identified and new imaging techniques could be used to test the effectiveness of new agents and further clarify the pathophysiology of AVS. No therapy that specifically lowers Lp (a) levels has been approved for clinical use.  相似文献   
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目的探讨主动脉瓣重度狭窄患者接受经导管主动脉瓣置换术(TAVR)治疗的有效性和安全性。方法回顾性选取2017年9月至2019年12月接受TAVR的主动脉瓣重度狭窄患者36例。收集患者的人口学、实验室检查、影像辅助检查等全部临床资料,对手术过程、成功率、并发症以及手术前后超声心动图结果等进行分析。结果患者平均年龄(72.42±6.14)岁,瓣膜置入成功率100%。与术前相比,术后第1天的脑钠肽、主动脉瓣最大跨瓣压差、主动脉瓣跨瓣流速差异均有统计学意义(均P<0.01),术后6个月随访左心室射血分数、左心室舒张末期内径及左心室收缩末期内径都有显著改善(均P<0.01)。并发症方面,住院期间1例(2.8%)患者因三度房室传导阻滞行永久性起搏器植入;术后1周有2例(5.6%)患者存在轻度瓣周漏(<2 mm),术后6个月随访时只有1例(2.8%)患者存在轻度瓣周漏;术后6个月随访时1例(2.8%)患者缺血性卒中。结论主动脉瓣重度狭窄患者行TAVR治疗有较好的安全性和有效性,可有效改善左心室重塑。  相似文献   
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目的:调查心脏机械瓣膜置换术(mechanical heart valve replacement,MHVR)术后长期抗凝治疗病人的满意度,并分析其影响因素,为临床治疗提供依据。方法:采用方便抽样的方法选取贵州省某三级甲等医院MHVR术后146例病人为研究对象,采用中文版抗凝治疗满意度量表(Anti-Clot Treatment Scale,ACTS)对其抗凝治疗满意度进行调查,采用单因素、多元逐步回归分析对抗凝治疗满意度的影响因素进行分析。结果:多元逐步回归分析结果显示,影响MHVR术后病人抗凝治疗满意度的因素从大到小依次为出院后并发症发生情况、出院时长、医生能否调华法林剂量、出院后是否再次住院以及每次复查费用,可以解释满意度总变异的58.7%。标准化回归方程为满意度得分=0.262×出院时长-0.347×出院后并发症发生情况+0.239×医生能否调华法林剂量-0.219×出院后是否再次住院-0.130×每次复查费用。结论:对MHVR术后病人进行延续性护理时,应重点加强华法林用药的教育,提高用药依从性,严禁病人随意加量或减量,指导病人观察出血、血栓形成的信号,学会应对措施,同时及时告知医生,减少并发症的发生。  相似文献   
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