心房颤动自发复律对老年患者左房功能的影响

目的本文探讨老年患者心房颤动自发复律后心房功能恢复的特点.方法采用SONOS 5500型彩色多普勒血流显像仪,观察20例老年对照组和20例非瓣膜病阵发性心房颤动(PAF)患者在心房颤动自发复律后24 h,72 h及7 d左心房收缩功能.观察以下指标:①左房内径LAD和左室内径LVD;②左室射血分数(LVEF);③二尖瓣E峰峰值速度E(cm/s);④二尖瓣A峰峰值速度A(cm/s);⑤取心尖四腔切面AQ技术观察左房:左房最大容积LAVmax,左房最小容积LAVmin,左房收缩期前容积LAVp,左房主动排空容积LAAEV=LAVp-LAVmin,左房主动排空分数LAAEF(%)=LAAEV/LAVp.结果老年PAF组较老年对照组左房内径[(4.24±0.43)cm vs(3.83±0.22)cm,P＜0.05]及左房容积[(70.43±12.70)ml vs(46.2±4.91)ml,P＜0.05]增大;二尖瓣峰流速A(cm/s)在心房颤动自发复律后24 h,48 h明显降低,7 d有所增高,但仍较对照组低[(45.4±12.37)cm/s;(56.64±16.24)cm/s;(65.01±13.58)cm/s vs(74.55±5.97)cm/s,P＜0.05];老年PAF组自发复律后LAAEF(%)降低,至7 d部分恢复,仍较对照组明显降低[(15.72±5.22)%;(16.42±5.20)%;(18.89±7.70)% vs(34.65±7.83)%,P＜0.05].结论老年心房颤动患者左房内径和左房容积增大,心房颤动自发复律7 d时LAAEF仍降低.由于自发复律后仍存在左房收缩功能障碍,且窦性心律难以维持,因此对于左房容积增大的老年PAF患者,抗凝治疗非常重要.     

经导管线性消融术对左心房功能影响的研究

目的评价左心房线性消融术对心房颤动（房颤）患者左心房功能的影响。方法选择30例Carto系统标测指导下行左心房线性消融术的阵发性房颤患者，应用超声心动图测定其消融术前1～3d、术后3个月静息时窦性心律下左心房容积指标、二尖瓣口A波速度峰值（VA）及左心房射血力，分析消融术前后左心房功能的变化。结果消融术后反应左心房辅泵功能的指标左心房射血力、VA、左心房主动排空容积、左心房主动排空分数、左心房总排空分数显著下降，反应左心房管道功能的左心房管道容积增加，反应左心房储存功能的指标左心房总排空容积、左心房最大容积无明显变化。结论Carto系统标测下左心房线性消融术后左心房辅泵功能下降，管道功能增强，而储存功能无显著改变。     

环肺静脉射频消融心房颤动对左心房结构和功能的影响

目的评价环肺静脉射频消融心房颤动（房颤）对左心房结构和功能的影响。方法对98例房颤患者环肺静脉射频消融术前及术后1年行超声心动图检查。分别测量左心房内径（LAD）、左心房收缩末容积（LAESV）、左心房舒张末容积（LAEDV）、二尖瓣血流速度峰值（VA）并计算左心房管道容积、左心房排空容积、左心房射血分数（LAEF）。结果环肺静脉消融术后LAD、LAESV、LAEDV、左心房排空容积较术前减小（P〈0．05）,管道容积较术前增大（P〈0．05）,VA、LAEF与术前比较差异无统计学意义（P〉0．05）。结论房颤环肺静脉隔离术后左心房结构及功能发生重构。术后左心房的内径和容积较术前减小;房颤环肺静脉隔离术后左心房的机械功能发生变化,左心房的储存功能降低,左心房的辅助泵功能无明显变化,左心房的管道功能增强。     

不停跳冠状动脉移植术后心房颤动危险因素分析

目的:分析不停跳冠状动脉移植术(OPCABG)后,心房颤动发生的临床相关因素,为临床预防和治疗术后发生的心房颤动(AF)提供参考依据。方法:收集大兴区人民医院2013年1月至2016年12月期间,128例OPCABG患者,观察围术期的相关临床资料,按术后是否发生AF,分为AF组42例和非AF组86例。对比两组患者的临床资料,分析患者年龄、左心房内径(LAD)、左心室射血分数(LVEF)、术前动脉氧分压、右冠状动脉主干狭窄(≥70%)等因素与OPCABG术后AF发生的相关性。结果:OPCABG术后AF发生率为32.8%,多发生于术后1~3d。两组间比较显示:AF组年龄、左心室射血分数、左心房内径、动脉氧分压、右冠状动脉主干狭窄(≥70%)与非AF组比较,差异有统计学意义(P0.05)。多因素Logistic分析结果提示:年龄、左心房内径、右冠状动脉主干狭窄(≥70%)是OPCABG术后发生AF的危险因素。结论:OPCABG术后AF的发生与年龄、左心房内径、右冠状动脉主干狭窄(≥70%)密切相关。     

冠状动脉旁路移植术后心房颤动的原因及防治

目的讨论冠状动脉旁路移植术(CABG)后心房颤动(AF)的发生原因及防治方法.方法对1998-2003年102例CABG术后患者(其中21例发生AF)进行回顾性研究分析.分析患者的临床资料,包括:年龄、性别、射血分数(EF)、左心房大小、心电图、心肌梗死情况、高血压病史、糖尿病史、搭桥支数、体外循环时间、升主动脉阻断时间、术前术后用药情况、AF患者的药物复律及电复律情况.结果CABG术后AF发生率20.6%.应用胺碘酮后转复窦性心律10例,直流电复律3例,应用β受体阻滞剂后自动转复窦性心律3例,持续心房颤动3例,术后早期死于低心排血量2例.结论CABG术后AF的发生与多因素相关.围术期应用β受体阻滞剂、胺碘酮以及术中良好的心肌保护可降低术后心室率,减少AF的发生.术后应积极控制心室率,应用胺碘酮转律对CABG术后AF患者是较好的安全的手段.     

递进式射频消融逆转伴持续性心房颤动“扩张型心肌病”20例的疗效

目的评价递进式射频消融对于心脏扩大的持续性心房颤动的临床效果。方法20例心脏扩大的持续性心房颤动患者接受在接触式三维标测系统(CARTO)指导下的递进式射频消融治疗,术中尽量终止心房颤动。手术6个月后进行随访,比较患者术前及术后的症状、左心房前后径、左心室舒张末内径、左心室收缩末内径、左心室射血分数。结果 (1)术中有40%的患者在消融过程中直接转复为窦性心律,其余经过电复律后转为窦性心律;(2)术后有15%的患者为阵发性心房扑动,85%的患者维持窦性心律;(3)术后患者症状明显好转,左心房前后径、左心室舒张末内径、左心室收缩末内径纽约心脏协会(NYHA)心功能分级较术前明显好转,差异有统计学意义(P<0.01);左心室射血分数较术前提高,差异有统计学意义(45.00%±15.00%vs.36.50%±19.50%,P<0.05)。结论对于高度选择性的伴有心脏扩大的持续性心房颤动患者进行递进式射频消融治疗是安全的,术后大部分患者可以维持窦性心律,同时心腔发生了逆重构,左心室收缩功能得以改善,心功能不全症状好转。     

B型利钠肽与孤立性心房颤动

目的:探讨B型利钠肽(BNP)与孤立性心房颤动(AF)的血栓事件发生、复律及再发之间的关系。方法:103例孤立性AF患者行食道超声(经食道超声心动图)、头颅计算机断层摄影术或磁共振(CT／MRI)检查及血BNP测定。探讨BNP在AF血栓事件及其相关因素中的作用。根据血栓事件将患者分为有血栓事件组(n=15)和无血栓事件组(n=88)。对于有复律指征的患者,根据AF复律及再发情况分为复律不成功患者(复律失败或随访期内再发,n=16)和复律成功患者(复律成功并随访期内维持窦性心律,n=7),分别进行对比研究。结果:服药后无血栓事件组BNP降低幅度优于血栓事件组,有显著性显异(P<0．05)。复律成功患者较复律不成功患者BNP水平低[(60±32)ng／L比(178±70)ng／L,P<0．05]、病程短[(3．0±1．9)个月比(7．6±2．5)个月,P< 0．05]和左心房内径小[(42．3±3．4)mm比(48．6±5．1)mm,P<0．05],均有显著性差异。多因素Logistic回归分析: BNP是预测孤立性AF血栓事件的独立因素(P<0．05);BNP、左心房内径和AF病程是预测AF复律及再发的独立因素(P均<0．05)。结论:BNP可作为预测孤立性AF血栓事件和AF复律与再发的临床指标。     

心房颤动患者经导管射频消融术后不同时期左心房结构及功能的动态变化

目的:观察射频消融术对阵发性和持续性心房颤动(房颤)患者左心房结构和功能不同时期的影响。方法:临床诊断房颤的79名患者作为研究对象(阵发性房颤组65例、持续性房颤组14例),随访1年,行超声心动图检查监测左心房最大面积(左心房左右径×上下径)、左心房最大容积(LAVmax)、左心房最小容积(LAVmin)、左心房P容积(LAVp)等左心房结构指标,并通过左心房被动射血分数(LAPEF),左心房主动射血分数(LAAEF),左心房排空容积等指标探讨左心房功能的变化。体检非房颤人群22例作为对照组。全部数据采用SPSS17.0软件包进行统计学分析。结果:①消融术前检测显示:房颤组左心房最大面积、LAVmax、LAVmin均高于正常对照组(P0.05);并且持续性房颤组左心房增大更显著(P0.05)。房颤组LAAEF低于正常对照组(P0.05),其中持续性房颤组下降更明显(P0.05)。LAPEF及左心房排空容积各组间差异无统计学意义。②两组房颤患者术后左心房最大面积、LAVmax较术前均有变小(P0.05),但两者出现变化的时间点不同,阵发性房颤组在术后1年明显变小(P0.05),持续房颤组在术后近期就出现明显变小(P0.05)。两组LAAEF、LAPEF、排空容积等较术前均无显著性变化。③持续性房颤组左心房最大面积术后近期、中期变化率大于阵发性房颤组(P0.05),但至术后1年变化率两者差异无统计学意义。结论:经导管射频消融术能缩小房颤患者增大的左房结构,近、中期在持续性房颤患者更加显著;经导管射频消融术本身对左心房功能无明显影响。     

氯沙坦联合胺碘酮治疗慢性心力衰竭伴心房颤动复律后的临床观察

目的观察氯沙坦和胺碘酮联用对慢性心力衰竭合并心房颤动复律后的心房颤动复发率及对左心房功能的影响。方法将60例慢性心力衰竭合并心房颤动（心房颤动持续时间≤1年）复律后病人随机分为治疗组（氯沙坦和胺碘酮合用）和对照组（胺碘酮单用）。观察两组口服药物6个月内心房颤动复律后的心房颤动复发率及对左心房功能的影响。结果6个月内治疗组2例退出，完成观察28例；对照组2例退出，完成观察28例。随访6个月，治疗组复发率为21．43％，对照组复发率为46．43％，两组比较有统计学意义（P〈0．05）；治疗组左心房内径缩小，心房压降低，治疗前后比较差异有统计学意义（P〈0．05），对照组治疗前后比较差异无统计学意义（P〉0．05）。结论氯沙坦与胺碘酮联用可明显减少慢洼心力衰竭合并心房颤动病人复律后心房颤动的复发，较单用胺碘酮有效，可能与氯沙坦逆转左心房扩大，降低左心房压力有关。     

冠状动脉旁路移植术后心房颤动的高危因素分析

目的　研究冠状动脉旁路移植术 (CABG)后心房颤动 (AF)的发病特点 ,分析AF的高危因素。方法　采用回顾性研究的方法 ,观察我院CABG患者 2 35例 ,监测手术前后心电图、2 4h动态心电图、心肌酶谱、心脏收缩功能、左心房内径、体外循环及主动脉阻断时间、和电解质变化等。结果　 2 35例患者CABG术后 4 2例 (17 9% )发生AF ,81%的AF发生于术后 1～ 3d ,持续 (12 0± 9 14 )h ,95 2 %患者 2 4h内恢复窦性心律 ;高龄 (≥ 70岁 )、低钾血症 (≤ 3 5mmol/L)、低镁血症 (≤ 0 70mmol/L)、左心功能不良[射血分数 (EF)≤ 0 4 0和 /或缩短分数 (FS)≤ 0 2 4 ]、左心房内径≥ 35mm、右冠状动脉狭窄≥ 70 %的患者术后AF发生率明显高于其他患者 (P分别为 0 0 0 1、0 0 0 9、0 0 16、0 0 30、0 0 36和 0 0 4 4 ) ;应用胺碘酮患者AF发生率明显降低。结论　低镁血症、左心房增大、右冠状动脉病变是术后AF的相关因素 ;高龄、左心室功能不良、低钾血症是术后AF的独立高危因素 ;预防应用胺碘酮能明显降低术后心室率 ,有效地抑制术后AF的发生 ,促进AF转复 ,明显改善左心室功能 ,并且具有较好安全性和耐受性 ,是术后AF的保护因素     

Serial evaluation of left atrial dimension after cardioversion for atrial fibrillation and relation to atrial function

The size of the left atrium is usually increased during atrial fibrillation (AF). The aim of the present study was to evaluate changes in left atrial (LA) dimension after cardioversion for AF, and the relation between LA dimension and atrial function. The initial study population included 171 consecutive patients. Patients who had spontaneous cardioversion to sinus rhythm (56 patients) were compared with patients who had random cardio-version with drugs (50 patients) or direct-current (DC) shock (50 patients). Echocardiographic evaluations included LA size and volume. LA passive and active emptying volumes were calculated, and LA function was assessed. Atrial stunning was observed in 18 patients reverted with DC shock and in 7 patients reverted with drugs. The left atrium was dilated in all patients during AF (48 +/- 5 mm). The size of the left atrium decreased after restoration of sinus rhythm in all patients with spontaneous reversion to sinus rhythm, in 73% of patients reverted with drugs, and in 50% of patients reverted with DC shock. The comparison between patients with a normal mechanical atrial function and patients with reduced atrial function showed that a higher atrial ejection force was associated with a more marked reduction in LA size after restoration of sinus rhythm. A relation between LA volumes and atrial ejection force was observed in the group of patients with depressed atrial mechanical function (r = -0.78; p <0.001). The active emptying fraction was lower, although not significantly, in this group, whereas the conduit volume was increased. Thus, a depressed atrial mechanical function after cardioversion for AF was associated with a persistence of LA dilation.     

心房颤动复律前后左房结构和功能变化的超声心动图研究

目的应用超声心动图观察心房颤动(简称房颤)患者复律前后左房结构和功能的变化。方法选择房颤患者20例,按心脏复律的方式分为直流电复律组7例,药物复律组13例,分别于复律前、复律后第1天、第3天、第7天、第1个月时应用超声心动图测定左房内径和容积,记录二尖瓣血流频谱A峰流速(VA)、A峰速度时间积分(A-VTI)、心房充盈分数(AFF)和左房射血力(LAEF)。分析左房内径、容积变化与左房收缩功能的关系。应用心房肌超声组织定征技术在左房后壁心肌和心包处测量背向散射积分值(IBS)及背向散射积分周期变异幅度(CVIB)评价心肌组织的声学特征。结果房颤时所有患者均存在左房扩大,而恢复窦性心律后直流电复律组和药物复律组的左房上下径均显著降低(P<0.05或0.01)。恢复窦性心律后第1天、第3天直流电复律与药物复律组比较,左房最大和最小容积显著增大(P<0.05或0.01),VA、A-VTI、AFF和LAEF明显降低。房颤时左房心肌标化IBS较健康对照组增大,而CVIB则降低(P均<0.01),直流电复律组恢复窦性心律后第1天、第3天左房心肌标化IBS及CVIB与房颤时比较无差异(P>0.05),而药物复律组左房IBS%与房颤时和直流电复律组比较显著降低,CVIB则显著增大。恢复窦性心律后第7天、第1个月时,两组左房IBS%与房颤时比较均显著降低,CVIB显著增大(P均<0.01),两组无差异。结论两种复律方式成功复律后随时间推移均可改善房颤患者的左房结构重构和功能。     

The left atrial function index: a rhythm independent marker of atrial function.

AIMS: This study evaluates a simple echocardiographic rhythm independent expression of left atrial (LA) function, 'the left atrial function index' (LAFI). BACKGROUND: Quantitation of LA function is challenging and often established parameters including peak A are limited to sinus rhythm (SR). We hypothesized that atrial function could be characterized independent of rhythm by combining analogues of LA volume, reservoir function and LV stroke volume. METHODS: Seventy-two patients with chronic atrial fibrillation (CAF) were followed for six months post cardioversion (CV). Thirty-seven age matched healthy subjects were controls. The LAFI = LAEF x LVOT-VTI/LAESVI (LAEF = LA emptying fraction, LAESVI = maximal LA volume indexed to BSA, LVOT-VTI = outflow tract velocity time integral). RESULTS: The LAFI pre-CV in the CAF group was depressed vs controls (0.10 +/- 0.05 vs 0.54 +/- 0.17; P = 0.0001). Post-CV, LAFI was lower in persistent AF than in those restored to SR (AF vs SR: 0.08 +/- 0.03 vs 0.15 +/- 0.08; P = 0.0001), improved progressively in SR and was unchanged when AF persisted. CONCLUSION: The LAFI, a simple, rhythm independent expression of atrial function, appears sensitive to differences between individuals in AF and those restored to SR and justifies clinical and investigative applications.     

Stunning of the left atrium after pharmacological cardioversion of atrial fibrillation

INTRODUCTION: Stunning of the left atrium and atrial appendage is a well known but not fully clarified phenomenon observed during the cardioversion of atrial fibrillation regardless of the cardioversion method attempted. AIM: To assess the effects of propafenone and amiodarone on left atrium and left atrial appendage contractility. METHODS: Forty patients with paroxysmal atrial fibrillation (20 females, 20 males), aged 60-83 (mean 72.0+/-10.1) years, were enrolled into the study. Half of these patients had sinus rhythm restored by the administration of oral propafenone (150-300 mg) and the remaining 20 patients were treated with intravenous amiodarone (150-450 mg). The control group consisted of 20 patients (10 females, 10 males) aged 52-78 (mean 61.2+/-9.3) years with sinus rhythm and no history of atrial fibrillation. All the patients had a transthoracic (TTE) and transesophageal (TEE) echocardiography performed while still in the AF, before drug administration and 1 hour after sinus rhythm restoration. RESULTS: All haemodynamic parameters of the left atrium measured after the sinus rhythm restoration were significantly worse when compared with the control group. Left atrial fractional shortening and total atrial fraction were significantly lower after propafenone than amiodarone (8.6+/-3.6% vs 11.7+/-5.5%, p<0.05; and LA FC 16.2+/-5.3% vs 23.3 (+/-6.3)% respectively, p<0.05). Doppler echocardiographic parameters included in the analysis such as mitral flow and superior left pulmonary vein flow were significantly lower in the sinus rhythm restoration group than in the control group. Among them the end-diastolic mitral flow velocity amplitude and flow velocity integral as well as the maximum pulmonary retrograde velocity were significantly worse in the group treated with propafenone than in patients receiving amiodarone. All the atrial appendage Doppler velocity parameters were significantly reduced after the sinus rhythm restoration in both groups. In the patients treated with propafenone, values of these parameters were significantly decreased compared with the patients receiving amiodarone. CONCLUSIONS: Successful pharmacological cardioversion of atrial fibrillation causes the left atrium and left atrial appendage contractility impairment similar to that observed with other methods of the sinus rhythm restoration. Following the AF cardioversion the level of left atrial stunning is higher in the patients treated with propafenone than in subjects receiving amiodarone.     

Echocardiographic Parameters for Predicting Maintenance of Sinus Rhythm After Internal Atrial Defibrillation

Chronic atrial fibrillation (AF), which is refractory to external electrical direct current shock and/or pharmacologic cardioversion, may be successfully cardioverted using internal atrial defibrillation. To avoid unnecessary procedures, it is important to be able to predict which patients will revert to AF. Thirty-eight patients with chronic AF underwent successful internal atrial defibrillation and were followed for 6 months after restoration of sinus rhythm. Left atrial (LA) diameter, left ventricular ejection fraction, maximum LA appendage area, and peak emptying velocities of the LA appendage were analyzed to determine which of these factors were associated with recurrence of AF. Forty-nine percent of patients had a recurrence of AF within 6 months following internal atrial defibrillation. The preprocedural ejection fraction (mean ± SD 59 + 14% vs 57 + 13%, p = 0.63), LA diameter (4.2 ± 0.6 cm vs 4.5 ± 0.6 cm, p = 0.16), and LA appendage area (5.0 ± 1.5 cm² vs 5.8 ± 1.5 cm², p = 0.13) did not differ significantly between patients who maintained sinus rhythm and those who had recurrence of AF. Peak emptying velocities of the LA appendage before cardioversion were significantly lower in patients with recurrence of AF compared with patients who maintained sinus rhythm (0.26 ± 0.1 m/s vs 0.49 ± 0.17 m/s, p = 0.001). A peak emptying velocity <0.36 had a sensitivity of 82% and a specificity of 83% for predicting recurrence of AF.     

P wave dispersion and left atrial appendage function for predicting recurrence after conversion of atrial fibrillation and relation of p wave dispersion to appendage function

BACKGROUND: We investigated P wave dispersion and left atrial appendage (LAA) function for predicting atrial fibrillation (AF) relapse, and the relationship between P wave dispersion and LAA function. METHODS: Sixty-four consecutive patients with AF lasting /=5 days, LA size >/=45 mm, maximum P wave duration >/=112 ms, P wave dispersion >/=47 ms, spontaneous echo contrast, minimum LAA area >/=166 mm(2), and LAA emptying velocity <36 cm/sec were univariate predictors of recurrence (each P < 0.05). By multivariate analysis, LA size (P = 0.02), P wave dispersion (P < 0.001), and LAA emptying flow (P = 0.01) identified patients with recurrent AF. Their positive predictive values were 91, 97, and 72%, respectively. CONCLUSION: The increased P wave dispersion in addition to the dilated LA and the depressed LAA emptying flow can identify patients at risk of recurrent AF after cardioversion.     

附加扩大左房减容与直流电转复模式对瓣膜病合并心房颤动患者心房颤动的影响

目的研究在进行基础瓣膜置换或成形手术时附加左房减容和直流电复律术对瓣膜病合并心房颤动(简称房颤)患者房颤的影响。方法选取有心脏瓣膜病变且合并左房扩大病例298例,均伴有诊断明确的房颤病史,根据左房内径大小分成Ⅰ、Ⅱ、Ⅲ3组:左房内径40～59mm为Ⅰ组,共83例,60～79mm为Ⅱ组,共161例,80mm以上为Ⅲ组,共54例。按照住院号单双数随机将三组又分为2个亚组行瓣膜手术附加左房减容术和直流电转复为a组,未附加手术为b组;左房减容包括左房折叠和左房壁切除,直流电电转复包括电复律,起始量为10J,依次10J累加,最大达30J。如果a组自动复跳为窦性心律,依然加10J电击一次。所有病例均于术前口服可达龙并术后维持治疗。结果Ⅰa组和Ⅰb组术后早期和出院时的窦性转复率无明显差异,但随访9～12个月,Ⅰa组的窦性转复率明显高于Ⅰb组(35.3%vs28.6%P(0.05);Ⅱ组和Ⅲ组中a亚组的窦性转复率在术后早期、出院时以及随访期间均明显高于b亚组。Ⅰa组与在出院和随访期间窦性转复率高于Ⅱa、Ⅲa(44.1%vs34.4%、27.3%;35.3%vs30.0%、12.1%,P均(0.05),Ⅱa组在出院和随访期间窦性转复率亦高于Ⅲa组(34.4%vs27.3%;30.0%vs12.1%,P(0.05)。结论对于左房扩大的瓣膜病变伴房颤患者,在进行基础瓣膜置换或成形手术时附加左房减容和直流电复律手术,可以达到一个非常理想的房颤转复率和维持率,但左房内径达80mm以上的病例其远期效果不佳。     

Left atrial mechanical function after brief duration atrial fibrillation

ObjectivesThis study examined the effect of brief duration atrial fibrillation on left atrial and left atrial appendage mechanical function in humans with structural heart disease.BackgroundLeft atrial dysfunction and the development of spontaneous echo contrast (SEC) may follow the cardioversion of atrial fibrillation (AF) to sinus rhythm. This phenomenon has been termed “stunning” and is implicated in the development of atrial thrombus and embolic stroke. The effects of brief duration AF on left atrial mechanical function in humans are unknown.MethodsTwenty-four patients (23 men, aged 59.1 ± 12.7 years) with significant structural heart disease (ejection fraction 31.2 ± 9.0%, left atrial diameter 4.9 ± 0.4 cm) undergoing implantation of a ventricular cardiodefibrillator underwent transesophageal echocardiography to evaluate left atrial appendage emptying velocities (LAAeV) and SEC before, during and after a 15-min period of AF induced by rapid right atrial pacing. Atrial fibrillation was then permitted to terminate spontaneously within 5 min or was reverted with an endocardial direct current shock. Velocities and SEC were assessed in sinus rhythm pre-AF, during AF and immediately, 5 and 10 min after reversion to sinus rhythm.ResultsAtrial fibrillation terminated spontaneously in 10 patients after 16.1 ± 1.0 min. Endocardial direct current (DC) cardioversion of 10.4 ± 6.4 J was required in 14 patients after AF lasting 20 min. Mean LAAeV pre-AF (50.0 ± 17.5 cm/s) was not significantly different to LAAeV immediately (52.8 ± 16.7 cm/s), 5 min (54.3 ± 16.4 cm/s) or 10 min (53.7 ± 15.7 cm/s) after reversion to sinus rhythm. Atrial stunning defined as a reduction in LAAeV of >20% was not observed in any patient. Fourteen of 24 patients (58%) developed SEC during AF, which resolved within 30 s of AF termination. There were no significant differences between LAAeV in those patients reverting with DC shock (pre-AF 50.6 ± 16.2 cm/s vs. immediately post-AF 54.7 ± 16.6 cm/s) or in those patients with spontaneous reversion (pre-AF 48.9 ± 20.2 cm/s vs. immediately post-AF 49.8 ± 17.3 cm/s).ConclusionsSignificant left atrial stunning was not observed after brief duration AF in humans with structural heart disease. Transient left atrial SEC develops in a significant proportion of these patients during AF but resolves rapidly on reversion to sinus rhythm. These findings suggest that the risk of thromboembolism may be low after brief duration AF that terminates either spontaneously or with an endocardial DC shock even in patients with significant structural heart disease. These findings have important implications for recipients of implantable devices that are capable of atrial defibrillation in response to AF.     

Atrial and ventricular volume and function evaluated by magnetic resonance imaging in patients with persistent atrial fibrillation before and after cardioversion

Atrial fibrillation (AF) is the most common cardiac arrhythmia and 25% of those >40 years old will experience AF. Left atrial size and left ventricular function are independently related to cardiovascular morbidity and mortality. Our aim was to evaluate cardiac volume and function using magnetic resonance imaging in patients with persistent AF and to describe the changes after cardioversion (CV). Sixty consecutive patients with persistent AF and 19 healthy volunteers had cardiac volumes evaluated by cinematographic breath-hold magnetic resonance imaging. Patients with AF were evaluated before CV and at 1, 30, and 180 days after CV, if still in sinus rhythm. All atrial and ventricular volumes and left ventricular mass decreased and ejection fractions increased significantly after CV (p <0.0001 for all variables). Atrial and ventricular diastolic volumes increased significantly the day after CV. The atrial diastolic volumes had decreased significantly at 30 days and ventricular volumes at 180 days. The atrial systolic volumes decreased significantly the day after CV, but the ventricular systolic volumes remained constant the day after CV and decreased thereafter. Only the right atrial volumes were normalized 180 days after CV. The same results were found in a subgroup of patients with lone AF. In conclusion, reversal of atrial dimensions and function happened earlier than ventricular reversal after CV in persistent AF. Atrial reversal began immediately and ventricular reversal was not seen before 30 days after CV. Our results suggest that the changes to the left atrium and both ventricles caused by AF could be permanent and that CV of AF may be preferable.     

左房机械功能对持续性心房颤动电复律术后疗效的影响

目的探讨左房机械功能对持续性心房颤动(简称房颤)电复律术后疗效影响。方法选择30例持续性房颤成功电复律患者,应用超声心动图测定其电复律术后48 h静息时窦性心律(简称窦律)下最大二尖瓣口面积、A波速度峰值(PMA),E波速度峰值(PME),计算左房射血力,测量左房内径,随访2个月,分析左房机械功能指标与持续性房颤电复律术后复发的关系。结果有11例(36.7%)患者电复律术后2个月复发,复发组左房射血力较窦律维持组明显下降[(8.5±2.4)×10-5N vs(11.4±3.6)×10-5N,P=0.020〗;复发组6例左房机械功能低下,较窦律维持组(5例)显著升高(54.5%vs 26.3%,χ2=4.9,P=0.042)。而复发组左房内径有增大的趋势(37.3±4.1mm vs 34.4±4.2 mm,P=0.077)。结论左房机械功能低下是持续性房颤电复律术后近期复发的危险因素。