Evidence and Challenges in Left Atrial Appendage Management

This review aimed to discuss the anatomical properties of the left atrial appendage (LAA), its relationship with atrial fibrillation (AF), effectiveness of LAA occlusion (LAAO), techniques, and new devices used to perform this procedure. An electronic search was performed to identify studies, in the English language, on LAA management. Searches were performed on PubMed Central, Scopus, and Medline from the dates of database inception to February 2020. For the assessed papers, data were extracted from the reviewed text, tables, and figures, by two independent authors. Anticoagulant therapy for patients with AF has proven beneficial and is highly recommended, but it is challenging for many patients to maintain optimal treatment. Surgery is the most cost-effective option; surgical methods include simple LAA resection, thoracoscopic surgery, and catheter treatment. Each procedure has its advantages and disadvantages, and many prospective studies have been conducted to evaluate various treatment methods. In managing the LAA, dissection of the LAA, such as changes in its shape and size due to remodeling during AF, changes in autonomic nerve function, and thrombosis, must be understood anatomically and physiologically. We believe that early treatment intervention for the LAA should be considered particularly in cases of recurrent AF.Conclusion: SLET under artificial pneumothorax is feasible and safe in minimally invasive McKeown esophagectomy.     

Early and Middle-Term Results and Anticoagulation Strategy after Left Atrial Appendage Exclusion Using an Epicardial Clip Device

Objective: The present study aimed to evaluate short- and middle-term results and postoperative anticoagulation of left atrial appendage (LAA) exclusion with an epicardial clip device.Materials and Methods: From September 2017 to August 2019, 102 patients at our institution underwent epicardial LAA exclusion using the AtriClip device. Anticoagulation therapy was resumed in the very early postoperative period and continued for at least three months after surgery. The patients’ data were obtained by reviewing their medical records retrospectively.Results: The mean and median durations of follow-up was 510 ± 184 days and 482 days (range, 216–938 days), respectively. Successful LAA exclusion was confirmed in all but one patient. No device-related complications occurred during surgery. Postoperative computed tomography (CT) findings revealed no migration or displacement of the clips in any patient; however, small clots were observed at the LAA stump in seven patients. Stroke-free rate during the follow-up period was 98.9%.Conclusion: LAA exclusion using the AtriClip device was a feasible treatment method in terms of its early and middle-term safety and efficacy. In addition, our postoperative anticoagulation strategy could be optimal for maximizing the procedure’s merits, although further studies, involving a larger number of patients and longer duration of follow-up, are needed.     

Effects of Continuous Infusion of Low-dose Human Atrial Natriuretic Peptide (hANP) on the Lungs during Cardiac Surgery

Objective: The objective of this study was to determine the effects of a continuous infusion of low-dose hANP on the lungs during cardiac surgery in patients under cardiopulmonary bypass (CPB).Methods: We analyzed 30 consecutive cases of cardiac surgery performed at our hospital from 2007–2008. The patients were divided into a group that received hANP (hANP group) or a group that received saline and no hANP (N-hANP group). We measured various parameters before and after surgery using a PiCCO monitor.Result: There were no differences in the preoperative characteristics between the groups, although urine volume during the operation was significantly greater in the hANP group. After surgery, there were no significant differences between the groups in cardiac output index (CI), global enddiastolic volume index (GEDVI), intrathoracic blood volume index (ITBI), pulmonary blood volume index (PBI), extravascular lung water index (ELWI) and pulmonary vascular permeability index (PVPI), total protein, and creatine. In contrast, interleukin-6 (IL-6) and renin were significantly lower, and albumin was significantly higher in the hANP group.Conclusion: We found that low-dose hANP during open cardiac surgery inhibited the secretion and plasma activity of IL-6 and renin. Although there were no differences in lung circulatory parameters such as the amount of fluid in the pulmonary blood vessels between the two groups, we believe that the strong diuretic effect of hANP reduced third-space fluid retention caused by CPB.     

实时三维经食管超声心动图定量评价心房颤动患者左心耳形态及功能

目的探讨实时三维经食管超声心动图(RT-3D-TEE)定量评估心房颤动(AF)患者左心耳(LAA)形态和功能的可行性。方法选取56例拟接受射频消融术的阵发性AF患者(阵发组)、26例持续性AF患者(持续组)及同期11名健康人(对照组),采用RT-3D-TEE测量3组LAA各参数。结果与对照组比较,阵发组LAA舒张末期容积(LAA-EDV)、收缩末期容积(LAA-ESV)、开口最大面积(A_(max))及最小面积(A_(min))均增大,射血分数(LAA-EF)、最大排空速度(Vep)、面积变化率(A%)及直径变化率(D%)均减小(P均0.05);持续组LAA-EDV、LAA-ESV、A_(max)、A_(min)增大,LAA-EF、Vep、A%、D%减小(P均0.05);阵发组与持续组间各参数差异均无统计学意义(P均0.05)。LAA-EF与ESV (r=-0.73,P0.01)、EDV(r=-0.64,P0.01)、A_(max)(r=-0.36,P0.01)及年龄(r=-0.27,P=0.02)呈负相关,与A%、D%、Vep呈正相关(r=0.86、0.74、0.55,P均0.01),与D_(max)无明显相关(P0.05)。结论 RT-3D-TEE能定量分析AF患者LAA形态及功能变化,对于评估AF患者病情具有一定临床意义。     

Left Atrial and Left Ventricular Diastolic Function After the Maze Procedure for Atrial Fibrillation in Mitral Valve Disease: Degenerative Versus Rheumatic

The present study was aimed to compare the left atrial and left ventricular diastolic functions amongst the rheumatic and degenerative mitral valve disease patients in atrial fibrillation who reverted to normal sinus rhythm following Cox-maze procedure. We prospectively investigated the left atrial and left ventricular function with Doppler echocardiography, by dividing into the rheumatic (N = 105) and the degenerative group (N = 47). Over the follow-up period (mean: 4.4 ± 1.2 years in the rheumatic group, 4.8 ± 1.3 years in the degenerative group), the rheumatic group showed statistically significant decrease in A'' velocity and E'' velocity, on contrary to degenerative group (A'' velocity: mean decrease of 0.43 ± 0.13 cm/s in the rheumatic group, mean increase of 0.57 ± 0.11 cm/s in the degenerative group, p = 0.029, E'' velocity: mean decrease of 0.23 ± 0.17 cm/s in the rheumatic group, mean increase of 0.21 ± 0.15 cm/s in the degenerative group, p = 0.031). In addition, the rheumatic group showed statistically significant increase in E/E'' ratio than the degenerative group (mean increase of 4.49 ± 1.98 in the rheumatic group, mean increase of 1.74 ± 1.52 in the degenerative group, p = 0.047). Despite successful sinus rhythm restoration, the progressive loss of LA function as well as LV diastolic function is more prominent in the rheumatic group than the degenerative group. Therefore, differentiated strategies for postoperative surveillance are needed according to the pathology of mitral valve disease.     

Two Different Minimally Invasive Techniques for Female Patients with Atrial Septal Defects: Totally Thoracoscopic Technique and Right Anterolateral Thoracotomy Technique

Background: To compare the outcomes of totally thoracoscopic technique (TTS) vs. right anterolateral thoracotomy technique (RALT) in female patients undergoing minimal invasive atrial septal defect (ASD) correction.Methods: From March 2011 to January 2013, 125 female patients underwent minimally invasive atrial septal defect closure, of whom 62 patients were in the TTS group and 63 were in the RALT group.Results: Procedures were performed successfully in all patients without in-hospital mortality or major complications. cardiopulmonary bypass (CPB) time were 48.95 ± 15.63 min in TTS group, 31.4 ± 8.04 min in RALT group (p <0.001); the cross-clamp time were 26.92 ± 11.84 min in TTS group and 18.51 ± 6.11 min in RALT group (p <0.001). The length of incision in RALT group (6.02 ± 1.03 cm) was longer than TTS group (5.31 ± 0.68 cm) and the difference was significant (p <0.001). The overall satisfaction rate for the cosmetic results of TTS was 100% and was 96.83% (61/63 patients) in RALT patients. During follow-up, all patients in TTS group were satisfied expect two patients complained that scar was too long at groin. Reasons for a lower score in RALT group included the long scar in the chest; a RALT incision that was located too medially (coming off the bra line) and asymmetrical breast development.Conclusions: Both TTS and RALT are valid and reliable cosmetic surgical techniques for repairing ASDs in female patients. Both techniques allow excellent cosmetic and functional results in most female patients. The totally thoracoscopic technique may gain shorter incision and cosmetic results compared with RALT.     

高龄冠心病合并心房颤动患者行非体外循环冠状动脉旁路移植术中左心耳处理的回顾性队列研究

目的 本文旨在探讨左室射血分数(LVEF)降低的高龄冠心病合并心房颤动(房颤)患者在非体外循环冠状动脉旁路移植术(OPCABG)中同期处理左心耳的手术技巧及效果评价.方法 纳入2013～ 2018年,84例OPCABGLVEF降低(＜50％)的高龄(年龄≥70岁)冠心病合并房颤患者在我科行非体外循环冠脉搭桥术.男54例...     

Atrial natriuretic peptide and verapamil can prevent gentamicin induced acute renal failure in the rat

Summary: Calcium channel blockers are able to improve renal function in acute renal failure (ARF) and natriuretic peptides can also exert beneficial effects. At present it is unknown whether administration of atrial natriuretic peptide (ANP) and a calcium channel blocker given before a toxic lesion can prevent gentamicin induced ARF. the mechanisms of action of natriuretic peptides and calcium channel blockers are different and, as yet, it has not been clarified if combined administration can augment the effects on renal function. After a basal period we investigated the effects of verapamil (VER, 0.66 mg/kg), ANP, (30 μg/kg) and a combination of both (identical doses as described individually). the drugs were given intravenously for a period of 40 min (infusion period) before gentamicin (15 mg/kg, i.v.) was administered for induction of ARF. Basal values for glomerular filtration rate (GFR, mL/min) were around 1.8 with no differences between the groups. At the end of the infusion period (before application of gentamicin) GFR was significantly elevated with VER + ANP (3.13 ± 0.51), ANP (2.70 ± 0.59) and VER (2.34 ± 0.47) compared to controls (saline, 1.7 ± 0.48). After application of gentamicin GFR significantly dropped in the control group (0.77 ± 0.21, 0.75 ± 0.19, respectively), indicating development of ARF. In contrast with VER + ANP, ANP and VER GFR could be maintained for 30 min (2.47 ± 0.39, 2.28 ± 0.33, 2.22 ± 0.43, respectively) and 130 min (2.11 ± 0.32, 1.86 ± 0.29, 2.11 ± 0.28, respectively) after gentamicin. Moreover ANP and VER revealed natriuretic activity and, due to their vasorelaxing potency, also influenced arterial blood pressure. We conclude that both VER and ANP are able to prevent early gentamicin induced ARF when given before the toxic lesion. Both drugs induce hyperfiltration while infused, in particular when administered in combination.     

A Comparative Prospective Observational Study on the Use of Direct Oral Anticoagulants after Cardiac Surgery for the Management of Atrial Fibrillation

Purpose: Recently, guidelines recommended the use of direct oral anticoagulants (DOACs) for the management of non-valvular atrial fibrillation (NVAF). Postoperative atrial fibrillation (POAF) is the most common post-surgical complication of cardiac surgery, but the efficacy and safety of DOAC for POAF have rarely been investigated. We conducted a prospective observational study to investigate the efficacy and safety of DOAC administered immediately after POAF.Materials and Methods: In all, 135 patients that experienced POAF after cardiac surgery were treated with a DOAC. Primary endpoints were either bleeding or thromboembolic events. Secondary endpoints included changes in hemoglobin (Hb), prothrombin time (PT), activated partial thromboplastin time (APTT), serum creatinine (sCr), estimated glomerular filtration rate (eGFR), and pleural/pericardial effusion.Results: Patients were treated with apixaban (n = 31), edoxaban (n = 87), and rivaroxaban (n = 17). Major bleeding (p = 0.011) and gastrointestinal (GI) bleeding (p = 0.047) were significantly more frequent in the rivaroxaban group. Stroke was observed in one rivaroxaban group patient and none in the other two groups.Conclusion: DOAC as anticoagulation therapy for the early intervention of POAF following cardiac surgery is associated with a low incidence of major bleeding; a favorable safety profile and excellent efficacy were demonstrated for DOAC. Furthermore, our results indicate that the safety and efficacy of apixaban and edoxaban are better than rivaroxaban.     

心房肽对脑损伤后血脑屏障的影响与形态学研究

利用大鼠脑损伤模型，观察了脑损伤后血浆及伤区脑组织内心房肽含量变化，发现在脑损伤后６、７２ｈ血浆或脑组织内心房肽含量明显减少；脑损伤前经侧脑室或静脉内应用心房肽，可有效地缓解脑水肿并减少伤区脑组织内伊文思蓝含量；同期的超微结构观察表明，脑室或静脉内应用心房肽可减轻内皮细胞间的紧密连接开放程度。结果提示心房肽具有改善脑水肿、降低脑损伤后血脑屏障通透性的作用。     

The Effect of Renal Transplantation on Plasma Atrial Natriuretic Peptide

The changes in plasma atrial natriuretic peptide (ANP) werestudied in four adult patients after cadaveric renal transplantation.In three patients who achieved good renal function, the correctionof volume overload, as reflected by reduction in weight andright atrial pressure, was associated with a steady fall inplasma ANP and a parallel decrease in both fractional excretionof sodium and plasma cyclic guanosine monophosphate. The fourthpatient. with severe acute rejection, developed severe peripheraloedema, and fractional sodium excretion remained low despitehigh values of ANP.     

高渗氯化钠对心钠素及内源性洋地黄样物质的影响

比较３０例硬膜外阻滞择期手术病人，输入７．５％ＨＳ和５％ＧＳ后血浆ＡＮＰ、ＥＤＬＳ及血流动力学的变化。输入ＨＳ后ＡＮＰ明显升高，ＥＤＬＳ短暂降低，６０ｍｉｎ完全恢复，主动脉顺应性快速增加。输入ＧＳ后ＡＮＰ有增加趋势，但无统计学意义。ＥＤＬＳ显著降低，６０ｍｉｎ时仅为基础值的。ＴＰＲ持续增加，ＣＯ和ＳＶ短暂降低，并伴有血压明显下降。揭示ＨＳ可明显刺激ＡＮＰ分泌，减缓ＥＤＬＳ变化。