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991.
The MitraClip percutaneous mitral valve repair system, developed as an option for percutaneous mitral repair, was clinically introduced in 2007. From 2010 through 2012, 6 of our patients underwent mitral valve surgery after MitraClip failure. Their mean age was 75 ± 7.7 years (range, 62–87 yr). Three had undergone cardiac surgery previously. In 5 of the 6 patients, mitral regurgitation recurred after initially successful MitraClip deployment and was the indication for surgery. The mean interval between MitraClip implantation and surgery was 106 ± 86 days (range, 0–238 d).Mitral valve repair was feasible in 3 patients; the others underwent valve replacement. All the patients underwent additional cardiac procedures, because the MitraClip worsened existing conditions. Echocardiograms revealed sufficient valvular repairs. Two patients died during hospitalization, one of cerebral infarction and the other of bowel ischemia.Mitral valve repair after failed MitraClip therapy can be complex and a surgical challenge. Careful consideration should be given to appropriate patient selection for MitraClip therapy, because the MitraClip can cause existing pathologic valvular conditions to deteriorate substantially. The interval between MitraClip failure and corrective surgery should be as short as possible. The primary indication is an issue of ongoing discussion.  相似文献   
992.
The epidemiologic profile of infective endocarditis has changed substantially over the past few years, especially in industrialized countries. Our study evaluates the clinical and pathologic characteristics of infective endocarditis patients treated by cardiac surgery in China during a 12-year period.We retrospectively evaluated 220 surgically treated infective endocarditis patients and analyzed their changes from the beginning of 1998 through 2009. The mean age of the patients increased from 36.9 to 42.7 years during those 12 years (P=0.036). The chief predisposing disease was congenital heart disease (32.8%), rather than rheumatic heart disease (13.2%); this rate did not change significantly during the 12 years. The prevalent congenital lesion was bicuspid aortic valve, the rate of which (55.6%) increased significantly over the 3 time intervals studied (P=0.016). The frequency of infective endocarditis after non-dental surgical and nonsurgical intervention was significantly greater (23.3%) during 1998 through 2001, compared with the 2 intervals that followed (9%; P=0.019). Streptococcus viridans was the most frequent causative agent overall (25.6%). Forty-seven of the 220 patients (21.4%) carried the clinical diagnosis of some other form of heart disease before surgery, but at surgery they were found to have infective endocarditis as the fundamental disease process. Of 47 patients, 33 (70.2%) had either very small or no vegetations but had focal necrosis and inflammation of valve tissue that supported the diagnosis of infective endocarditis.  相似文献   
993.
Bioprosthetic heart valves can degenerate and fail over time. Repeat surgery as a means of replacement increases morbidity and mortality rates, and some patients are not candidates for reoperation. A newer treatment, percutaneous transcatheter valve-in-valve implantation, might delay or substitute for invasive procedures. We present the case of a 51-year-old woman, a poor candidate for surgery who had prosthetic tricuspid valve degeneration and stenosis. We successfully performed valve-in-valve placement of a Melody® valve, using a procedure originally intended to treat pulmonary valve conduit obstruction or regurgitation. To our knowledge, this is among the first case reports to describe the use of the Melody pulmonary valve in transcatheter valve-in-valve replacement for prosthetic tricuspid stenosis that was otherwise not correctable. Additional data and longer follow-up periods are necessary to gain an understanding of ideal indications and selection of patients for the percutaneous transcatheter treatment of tricuspid valve stenosis.  相似文献   
994.
背景:应用机械瓣和生物瓣行瓣膜置换是治疗终末期瓣膜病的有效手段,然而他们的临床应用受到多个因素的限制。具备生物活性的组织工程心脏瓣膜有潜力克服机械瓣和生物瓣的不足,选择适宜的种子细胞是组织工程心脏瓣膜研究的一个重要方面,许多成熟的体细胞和干细胞已被用于构建组织工程心脏瓣膜,然而尚未获得理想的结果。 目的:以构成瓣膜的细胞成分为基础,对用于构建组织工程心脏瓣膜的种子细胞、体外细胞种植方法的研究进行综述。 方法:由第一作者基于PubMed数据库和万方数据库应用计算机检索2000年1月至2012年12月相关的文章,英文检索词为"Tissue engineering,Heart valves,Cell",中文检索词为"组织工程,心脏瓣膜,细胞",优选文章内容与组织工程心脏瓣膜种子细胞直接相关,具备针对性和权威性,发表在权威杂志的文章共39篇进行综述。 结果与结论:瓣膜的细胞成分主要是内皮细胞和间质细胞,早期人们常用内皮细胞和成纤维细胞构建组织工程瓣膜,随着干细胞研究的深入,应用搏动性生物反应器种植间充质干细胞具有构建的组织工程瓣膜的潜力。  相似文献   
995.
背景:心脏瓣膜置换或成形同期行冠状动脉旁路移植手术的选择已成为目前治疗冠状动脉粥样化性心脏病合并心脏瓣膜病的发展趋势。目的:回顾性总结51例心脏瓣膜替换或成形同时行冠状动脉旁路移植手术的经验。方法:回顾性分析同期施行心脏瓣膜置换或成形及冠状动脉旁路移植患者51例临床资料,共移植旁路血管109支,同时行主动脉瓣置换10例,二尖瓣置换14例,二尖瓣置换联合三尖瓣成形8例,主动脉瓣联合二尖瓣双瓣置换4例,主动脉瓣、二尖瓣双瓣联合三尖瓣成形3例,二尖瓣成形7例,二尖瓣成形联合三尖瓣成形5例。结果与结论:置换生物瓣膜者9例,机械瓣膜者31例,二尖瓣成形11例,三尖瓣成形16例;共移植旁路血管109支,冠状动脉旁路移植平均搭桥(1.92±0.73)支;术后30 d内死亡4例。47例顺利出院,其中2例失访,45例随访3-48个月,1例半年后脑梗死,1例于术后1年多死于心脏功能不全,存活的43例心功能改善明显,均可进行一般的生活与活动。综合分析得出彻底解除瓣膜病变,充分保障心肌再血管化,保护心肌,尽量缩短主动脉阻断时间是手术成功的关键因素。  相似文献   
996.
目的:研究介入封堵术对重度三尖瓣反流的室间隔缺损的治疗效果。方法: 选取重度三尖瓣反流的室间隔缺损患者16例,三尖瓣返流的原因为右室局部心腔压力增高所致的高压血流直接冲击三尖瓣及其腱索而导致三尖瓣反流,其中行导管介入封堵6例,外科修补手术10例。比较两组患者术后三尖瓣返流程度(三尖瓣返流长度、三尖瓣返流面积、三尖瓣返流容积、三尖瓣返流速度、三尖瓣返流压差)、手术成功率、并发症发生率、术后住院时间、住院总费用、手术时间、正性肌力药物评分、术后第24h白细胞计数、CRP、心肌损伤标志物(cTNI、CK-MB、MYO)。结果: 术后三尖瓣返流量较术前显著减少。两组手术方式后的三尖瓣返流程度无统计学差异。导管介入组在手术时间、术后血管活性药物、术后第24h白细胞计数、CRP、心肌损伤标记物方面均优于外科手术组。在手术费用方面外科手术组与导管介入组、手术住院天数、并发症发生率两者无区别。结论:术前经过认真的超声评估,部分室间隔缺损合并三尖瓣重度返流的患者行介入治疗优于外科手术。  相似文献   
997.
ObjectivesThe purpose of this study was to characterize health status outcomes after transcatheter aortic valve replacement (TAVR) with a self-expanding bioprosthesis among patients at extreme surgical risk and to identify pre-procedural patient characteristics associated with a poor outcome.BackgroundFor many patients considering TAVR, improvement in quality of life may be of even greater importance than prolonged survival.MethodsPatients with severe, symptomatic aortic stenosis who were considered to be at prohibitive risk for surgical aortic valve replacement were enrolled in the single-arm CoreValve U.S. Extreme Risk Study. Health status was assessed at baseline and at 1, 6, and 12 months after TAVR using the Kansas City Cardiomyopathy Questionnaire (KCCQ), the Short Form-12, and the EuroQol-5D. The overall summary scale of the KCCQ (range 0 to 100; higher scores = better health) was the primary health status outcome. A poor outcome after TAVR was defined as death, a KCCQ overall summary score (OS) <45, or a decline in KCCQ-OS of 10 points at 6-month follow-up.ResultsA total of 471 patients underwent TAVR via the transfemoral approach, of whom 436 (93%) completed the baseline health status survey. All health status measures demonstrated considerable impairment at baseline. After TAVR, there was substantial improvement in both disease-specific and generic health status measures, with an increase in the KCCQ-OS of 23.9 points (95% confidence interval [CI]: 20.3 to 27.5 points) at 1 month, 27.4 points (95% CI: 24.2 to 30.6 points) at 6 months, 27.4 points (95% CI: 24.1 to 30.8 points) at 12 months, along with substantial increases in Short Form-12 scores and EuroQol-5D utilities (all p < 0.003 compared with baseline). Nonetheless, 39% of patients had a poor outcome after TAVR. Baseline factors independently associated with poor outcome included wheelchair dependency, lower mean aortic valve gradient, prior coronary artery bypass grafting, oxygen dependency, very high predicted mortality with surgical aortic valve replacement, and low serum albumin.ConclusionsAmong patients with severe aortic stenosis, TAVR with a self-expanding bioprosthesis resulted in substantial improvements in both disease-specific and generic health-related quality of life, but there remained a large minority of patients who died or had very poor quality of life despite TAVR. Predictive models based on a combination of clinical factors as well as disability and frailty may provide insight into the optimal patient population for whom TAVR is beneficial. (Safety and Efficacy Study of the Medtronic CoreValve® System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement; NCT01240902)  相似文献   
998.
Uhl''s anomaly is characterized by absence of the myocardial layer of the right ventricle, with opposition of the endocardium and epicardium. It is rarely associated with other congenital malformation. Here, we reported the rare association of Uhl''s anomaly with absent tricuspid valve in an infant.  相似文献   
999.
ObjectivesThis study was designed to assess hemodynamic changes in response to transcatheter tricuspid valve edge-to-edge repair (TTVR) and to identify hemodynamic predictors associated with mortality.BackgroundSevere tricuspid regurgitation (TR) is associated with high mortality. TTVR effectively alleviates heart failure symptoms, but comprehensive hemodynamic characterization of patients undergoing TTVR is currently lacking.MethodsThis international, multicenter study included 236 patients undergoing TTVR. Data from clinical assessment, echocardiography, intraprocedural right heart catheterization, and noninvasive cardiac output measurement were analyzed. Hemodynamic predictors for mortality were identified using linear Cox regression analysis and were used for stratification of patients with subsequent analysis of survival time.ResultsPatients (median age 78 years, 53% women) were symptomatic (89% in New York Heart Association functional class III or IV) because of severe TR (grade ≥3+ in 100%). TTVR significantly reduced TR at discharge (grade ≥3+ in 16%; p < 0.001), with a corresponding 19% reduction of the right atrial v wave (21 mm Hg vs. 16 mm Hg; p < 0.001) and an improvement in cardiac output (from 3.5 to 4.0 l/min; p < 0.01). Invasive mean pulmonary artery pressure, transpulmonary gradient, pulmonary vascular resistance, and right ventricular stroke work were significant predictors of 1-year mortality (p < 0.05 for all). Hemodynamic stratification by mean pulmonary artery pressure and transpulmonary gradient best predicted 1-year survival (p < 0.001). Although patients with pre-capillary dominant pulmonary hypertension showed an unfavorable prognosis (1-year survival 38%), patients without or with post-capillary pulmonary hypertension had favorable outcome (1-year survival 92% or 78%, respectively).ConclusionsInvasive assessment of cardiopulmonary hemodynamic status predicts survival after TTVR. Invasive hemodynamic characterization may help identify patients profiting most from TTVR.  相似文献   
1000.
Objective: To assess the viewing rate and reproducibility of areas of the papillary muscles (PMs) of foetal atrioventricular valves using spatio-temporal image correlation (STIC) in the rendering mode in congenital heart disease (CHD).

Methods: We retrospectively reviewed 40 4D-STIC volume datasets from different foetal CHD cases at a gestational age of 18w6d–35w6d. The following papillary muscles (PMs) were assessed: antero-lateral (MPAL) and postero-medial (MPPM) to the mitral valve and antero-superior (MPAS), inferior (MPI) and septal (MPS) to the tricuspid valve. To assess the valve viewing rate, percentages (%) were used. The concordance correlation coefficient (CCC) was used to assess inter-observer reliability.

Results: Two independent observers concluded that a complete examination of the PMs was impossible in 11 cases, yielding a viewing rate of 72.5%. The complete examination of the PMs of the tricuspid and mitral valves was possible by both examiners in 33/40 (82.5%) and 32/40 (80.0%) cases, respectively. We observed moderate to good inter-observer reliability with CCCs of 0.95, 0.92, 0.97, 0.96 and 0.97 for MPS, MPI, MPAS, MPAL and MPPM, respectively.

Conclusion: The viewing rate of PM areas in different CHDs using STIC in the rendering mode was moderate. The inter-observer reproducibility was moderate to good for all PM areas.  相似文献   

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