Percutaneous Left Atrial Appendage Closure Devices

Purpose of Review

Atrial fibrillation (AF) is the most common arrhythmia in humans. It is a major cause of morbidity and mortality as it impairs cardiac function and is a major risk of embolic stroke. Traditionally, thromboembolic risk of AF has been treated with system anticoagulation with intravenous, intramuscular, or oral anticoagulants. Although the novel oral anticoagulants (NOACs) have revolutionized stroke risk reduction in AF patients, they are associated with a significant risk of bleeding and may be contraindicated in certain patients. Embolic events in AF typically originate from thrombi that form within the left atrial appendage (LAA), especially in nonvalvular AF. Both surgical and percutaneous LAA closure techniques have been devised as alternatives to systemic anticoagulation. As surgical LAA closure is typically performed as an adjunct to other cardiac surgeries, the amount of eligible patients for this type of therapy may be limited.

Recent Findings

Excluding the LAA from the systemic circulation may reduce the risk of thromboembolism in AF. Recent technologic advances have led to the development of several percutaneously delivered devices that can occlude or exclude the LAA from systemic circulation. These devices may be purely endocardially delivered such as the Watchman (Boston Scientific, Maple Grove, MN) and Amulet (St. Jude Medical, Minneapolis, MN), or both endocardially and pericardially delivered such as the Lariat (Sentre-HEART, Palo Alto, CA). During Amulet and Watchman procedures, a transseptally delivered device composed of nitinol is placed in the LAA orifice, subsequently excluding the LAA from the systemic circulation. In the Lariat procedure, a magnet link is created between a transseptally delivered endocardial wire and epicardially delivered pericardial wire, followed by epicardial suture ligation of the LAA. Their use is steadily increasing in worldwide either through routine clinical use of approved devices or within clinical trials.

Summary

In this review, we describe the various devices available for percutaneous LAA closure, and the indispensable role of real-time transesophageal echocardiography in the periprocedural assessment and intraprocedural guidance of percutaneous LAA occlusion procedures.

     

Cardiac CT for Guiding Mitral Valve Interventions

Purpose of Review

The purpose of this paper is to review the current role of contrast-enhanced cardiac computed tomography (CT) in the peri-procedural planning of mitral valve (MV) repair.

Recent Findings

Cardiac CT is increasingly implemented in the peri-interventional management of patients undergoing MV repair or MV replacement due to its widespread availability and its ability to provide detailed information on the complex cardiac and valvular anatomy.

Summary

The complex anatomy of the MV challenges the management of minimally invasive MV repair with respect to device sizing and procedural planning. Advances in CT have enabled cardiac CT to provide critical information for the pre-procedural planning and post-procedural follow-up of MV repair. Therefore, it represents a key element in the improvement of the post-procedural outcome, the efficiency of implanted devices, and the prevention as well as advanced diagnostics of post-procedural complications. However, particular expertise is required to select adequate imaging protocols, perform comprehensive post-processing features, and to achieve specific quantitative image evaluation.

     

Echocardiography in Percutaneous Mitral Valve Interventions

Transcatheter therapies have emerged as an important treatment for patients with native mitral regurgitation and prosthetic valve paravalvular regurgitation. Echocardiography is critical to the success of these procedures. Echocardiographic guidance plays a central role in patient selection, procedural guidance, and post-procedure surveillance. Successful imaging support requires an understanding of the procedural technique, optimal views at different points in the procedure, and common pitfalls. Standardization of imaging protocols can help achieve optimal support during the procedure. New echocardiographic technologies, such as real-time 3D imaging, have enhanced the ability to provide guidance for these procedures. As percutaneous therapies for mitral valve disease continue to become more prevalent, echocardiography will continue to be a key modality for imaging guidance for these procedures.     

Sex Differences in Outcomes Following Left Atrial Appendage Closure

ObjectiveTo evaluate the effects of female sex on in-hospital outcomes and to provide estimates for sex-specific prediction models of adverse outcomes following left atrial appendage closure (LAAC).Patients and MethodsCohort-based observational study querying the National Inpatient Sample database between October 1, 2015, and December 31, 2017. Demographics, baseline characteristics, and comorbidities were assessed with the Charlson Comorbidity Index (CCI), Elixhauser Comorbidity Index score (ECS), and CHA₂DS₂-VASc score. The primary outcome was in-hospital major adverse events (MAEs) defined as the composite of bleeding, vascular, cardiac complications, post-procedural stroke, and acute kidney injury. The associations of the CCI, ECS, and CHA₂DS₂-VASc score with in-hospital MAE were examined using logistic regression models for women and men, respectively.ResultsA total of 3294 hospitalizations were identified, of which 1313 (40%) involved women and 1981 (60%) involved men. Women were older (76.3±7.7 vs 75.2±8.4 years, P<.001), had a higher CHA₂DS₂-VASc score (4.9±1.4 vs 3.9±1.4, P<.001) but showed lower CCI and ECS compared with men (2.1±1.9 vs 2.3±1.9, P=.01; and 9.3±5.9 vs 9.9±5.7, P=.002, respectively). The primary composite outcome occurred in 4.6% of patients and was higher in women compared with men (women 5.6% vs men 4.0%, P=.04), and this was mainly driven by the occurrence of cardiac complications (2.4% vs 1.2%, P=.01). In women, older age, higher median income, and higher CCI (adjusted odds ratio [aOR], 1.32; 95% confidence interval [CI], 1.21 to 1.44; P<.001), ECS (aOR, 1.04; 95% CI, 1.02 to 1.07; P=.002), and CHA₂DS₂-VASc score (aOR, 1.24; 95% CI, 1.10 to 1.39; P<.001) were associated with increased risk of in-hospital MAE. In men, non-White race/ethnicity, lower median income, and higher ECS (aOR, 1.06; 95% CI, 1.04 to 1.09; P<.001) were associated with increased risk of in-hospital MAE.ConclusionWomen had higher rates of in-hospital adverse events following LAAC than men did. Women with older age and higher median income, CCI, ECS, and CHA₂DS₂-VASc scores were associated with in-hospital adverse events, whereas men with non-White race/ethnicity, lower median income, and higher ECS were more likely to experience adverse events. Further research is warranted to identify sex-specific, racial/ethnic, and socioeconomic pathways during the patient selection process to minimize complications in patients undergoing LAAC.     

三种影像学测量技术对左心耳封堵器尺寸选择的指导价值

目的初步探讨CT血管造影(CT angiography,CTA)、经食管超声心动图(transesophageal echocardiography,TEE)和术中数字减影血管造影(digital subtraction angiography,DSA) 3种方法测量左心耳开口直径对选择适宜尺寸左心耳封堵器的指导价值。方法回顾性收集2015年12月1日至2019年3月31日在解放军总医院第一医学中心接受经皮左心耳封堵术的非瓣膜性房颤患者临床资料。所有入选患者同时采用CTA、TEE、DSA 3种方法测量左心耳开口直径,记录植入封堵器尺寸,采用Pearson相关性分析比较3种方法测量值与植入封堵器尺寸的相关性,采用BlandAltman一致性分析法比较3种方法测量值与所植入封堵器尺寸的一致性。结果共102例符合纳入和排除标准的患者入选本研究,均成功植入WATCHMAN封堵器。平均年龄(70. 1±9. 8)岁,CHA2DS2-VASc评分(评估非瓣膜性房颤成年患者发生卒中的风险)为(5. 11±1. 43)分,HAS-BLED评分(评估出血风险)(3. 61±1. 18)分。CTA测量左心耳开口直径[(22. 51±3. 55) mm]与DSA [(22. 22±3. 73) mm]接近,无统计学差异(q=0. 81,P=0. 12),两种方法的测量值均大于TEE [(20. 82±0. 36) mm,P均<0. 01]。封堵器尺寸与CTA、DSA、TEE测量的左心耳开口直径呈正相关(r=0. 93、0. 87、0. 83,P均<0. 01)。封堵器尺寸与CTA测量值的一致性界限最窄(-7. 83 mm,-2. 56 mm),差值为(-5. 19±1. 35) mm,95%置信区间为(-5. 46 mm,-4. 93 mm);与TEE测量值的一致性界限最宽(-11. 00 mm,-2. 77 mm),差值为(-6. 88±2. 10) mm,95%置信区间为(-7. 29 mm,-6. 47 mm)。结论 CTA、DSA、TEE测量左心耳开口直径能为选择左心耳封堵器适宜尺寸提供较好依据,其中CTA测量值与封堵器尺寸的相关性和一致性最佳。     

三种影像学测量技术对左心耳封堵器尺寸选择的指导价值

  目的  初步探讨CT血管造影(CT angiography, CTA)、经食管超声心动图(transesophageal echocardio-graphy, TEE)和术中数字减影血管造影(digital subtraction angiography, DSA)3种方法测量左心耳开口直径对选择适宜尺寸左心耳封堵器的指导价值。  方法  回顾性收集2015年12月1日至2019年3月31日在解放军总医院第一医学中心接受经皮左心耳封堵术的非瓣膜性房颤患者临床资料。所有入选患者同时采用CTA、TEE、DSA 3种方法测量左心耳开口直径, 记录植入封堵器尺寸, 采用Pearson相关性分析比较3种方法测量值与植入封堵器尺寸的相关性, 采用Bland-Altman一致性分析法比较3种方法测量值与所植入封堵器尺寸的一致性。  结果  共102例符合纳入和排除标准的患者入选本研究, 均成功植入WATCHMAN封堵器。平均年龄(70.1±9.8)岁, CHA2DS2-VASc评分(评估非瓣膜性房颤成年患者发生卒中的风险)为(5.11±1.43)分, HAS-BLED评分(评估出血风险)(3.61±1.18)分。CTA测量左心耳开口直径[(22.51±3.55)mm]与DSA[(22.22±3.73)mm]接近, 无统计学差异(q=0.81, P=0.12), 两种方法的测量值均大于TEE[(20.82±0.36)mm, P均 < 0.01]。封堵器尺寸与CTA、DSA、TEE测量的左心耳开口直径呈正相关(r=0.93、0.87、0.83, P均 < 0.01)。封堵器尺寸与CTA测量值的一致性界限最窄(-7.83 mm, -2.56 mm), 差值为(-5.19±1.35)mm, 95%置信区间为(-5.46 mm, -4.93 mm); 与TEE测量值的一致性界限最宽(-11.00 mm, -2.77 mm), 差值为(-6.88±2.10)mm, 95%置信区间为(-7.29 mm, -6.47 mm)。  结论  CTA、DSA、TEE测量左心耳开口直径能为选择左心耳封堵器适宜尺寸提供较好依据, 其中CTA测量值与封堵器尺寸的相关性和一致性最佳。     

三维超声心动图测定正常人及二尖瓣病变伴或不伴房颤患者左心耳容量及其收缩功能

目的:探讨三维超声心动图评价左心耳功能的价值.方法:采用三维超声心动图对52例正常人及二尖瓣病变伴或不伴心房纤颤患者测定左心耳容量及其收缩功能,并与二维超声心动图和多普勒超声心动图比较.结果:根据左心耳容量测定计算出的左心耳射血分数(EFv)与左心耳峰值血流排空速度(Pev)相关良好(r＝0.818,P＜0.01).根据左心耳面积测定计算出的左心耳射血分数(EFa)与Pev的相关性低于前者(r＝0.7444,P＜0.01).将所有患者的EFv与EFa进行比较,虽然两者间未见明显差异(P＞0.05),但在重复性检验中EFa的范围和两测量数值之差的均数加减标准差都大于EFv的相应数值,左心耳容量在正常人明显小于有二尖瓣病变的患者,而收缩功能则前者明显高于后者(P值均＜0.01).在相同二尖瓣病变患者之间进行比较,合并房颤者左心耳容量大于窦性心率者,而左心耳收缩功能则前者低于后者(P值均＜0.05).另外,二尖瓣病变合并房颤者的左心耳自发性"超声造影"发生率高于窦性心率者.结论:用三维超声心动图测量左心耳容量和评价其收缩功能是可行的,评价左心耳功能时较二维超声心动图更准确,二尖瓣病变患者的左心耳容量增加,收缩功能减低,常伴左心耳自发性"超声造影",上述改变在合并房颤者更明显.     

二尖瓣狭窄球囊扩张术前后左心耳血流动力学改变的超声研究

目的探讨风湿性心脏病二尖瓣狭窄患者PBMV 术后左心耳功能和血流动力学改变.方法符合PBMV手术适应症的风湿性心脏病二尖瓣狭窄患者23例,其中窦性心律17 例, 心房颤动6例, 均于术前术后3 天内应用经胸及经食道超声技术检测二尖瓣瓣口面积、二尖瓣最大和平均跨瓣压差、左心房面积变化率和射血分数、左心耳最大容积、最小容积和射血分数.应用脉冲多普勒技术记录左心耳血流频谱.PBMV术中穿刺房间隔成功后,鞘管置入左心房,测量左房最大压力、最小压力和平均压力.结果记录到的23例患者中,窦性心律患者左心耳血流呈典型的双相频谱,房颤患者左心耳血流频谱则有两种类型,即呈 "无血流状态"和"锯齿波"形.与PBMV术前比较,术后二尖瓣瓣口面积扩大,二尖瓣最大和平均跨瓣压差下降,左房压力和肺动脉压力减低,左房面积和射血分数、左心耳容积和射血分数无显著性变化,左心耳血流显著加速.相关分析表明PBMV术后左心耳最大前向血流速度与二尖瓣口面积正相关(r=0.51,P<0.05),与二尖瓣平均跨瓣压差负相关(r=-0.61,P<0.01),与左房平均压负相关(r=-0.64,P<0.01).结论成功的PBMV术后左心耳血流动力学得到改善,但左心耳功能恢复是一个延迟改变的过程,提示 PBMV术后仍应充分抗凝以减少血栓形成.     

经食管实时三维超声心动图联合双源CT在左心耳封堵术及其随访中的应用价值

目的探讨经食管实时三维超声心动图(RT3D-TEE)联合双源CT(DSCT)在经皮左心耳封堵(PCLAA)术及其随访中的应用价值。方法选取行PCLAA术的患者17例。术前运用RT3D-TEE和DSCT分别观察左心耳(LAA)的立体结构与整体形态,测量锚定区直径。术后12个月复查,评价封堵疗效。结果 17例患者成功进行LAmbre^TM经皮左心耳封堵术。术前RT3D-TEE显示LAA锚定区直径为(21.36±3.88)mm。DSCT将LAA整体形态分为四型:菜花型7例、风向标型5例、仙人掌型2例和鸡翅型3例。DSCT显示LAA锚定区直径为(25.97±3.96)mm。术后12个月复查发现所有患者封堵器形态良好,位置固定,心功能良好。2例患者封堵器边缘仍有少量残余分流。RT3D-TEE、DSCT显示LAA锚定区直径与造影所测值的相关性分别为(r=0.77,P=0.000 3和r=0.63,P=0.006 8)。Bland-Altman散点图显示LAA锚定区直径的RT3D-TEE和造影所测值中,有15个数据点[88.24%(15/17)]在一致性界限(-16.4、22.2...     

人工二尖瓣置换者左房室平面的沿心脏长轴运动

本研究将人体心脏内标志物为观察对象,了解左房室平面沿心脏长轴的运动。采用二维超声、多普勒超声等方法,观察45例人工二尖瓣置换病人的二尖瓣后缘的长轴运动特征。结果见人工二尖瓣长轴运动超声参数与左室收缩功能指标相关良好,证实以人工二尖瓣金属环后缘为标志的左房室平面存在确切的沿心脏长轴方向运动。并且获得以人工瓣环为标志物的左房室平面在超声心动图和低频多普勒超声上的长轴运动数据,认为左房室瓣环心脏长轴运动在维持左室收缩功能中具有重要的作用。