Rate of conversion and recurrence after sotalol treatment in patients with direct current-refractory atrial fibrillation

BACKGROUND: A number of patients with persistent atrial fibrillation (AF) will not have sinus rhythm (SR) restored by direct current (DC) cardioversion. HYPOTHESIS: In patients with DC-refractory AF, oral pretreatment with sotalol increases the success rate at DC cardioversion. METHODS: Consecutive patients with persistent AF, refractory at a first DC cardioversion, were prospectively included. A comparative group of patients with AF not refractory at DC cardioversion was studied. Oral sotalol treatment was started after unsuccessful DC cardioversion and given at least 7 days before renewed cardioversion. Four weeks after cardioversion, an electrocardiogram was performed. RESULTS: In all, 53 patients were enrolled in the study. Forty-three (81%) in the sotalol group regained sinus rhythm (SR): 10 (19%) of these converted pharmacologically and 33 (62%) after a second DC cardioversion; SR was never restored in 10 patients (19%). After 4 weeks, SR was maintained in 29 patients (67%). The comparative group included 132 patients and differed significantly from the DC-refractory patients only with regard to weight. After 4 weeks, SR was maintained by 50 patients (37%) in this group. CONCLUSIONS: In patients with persistent AF refractory to DC cardioversion, oral pretreatment with sotalol results in a high rate of SR restoration, either pharmacologically or by DC cardioversion. Maintenance of SR at 4 weeks is of sufficient clinical relevance to consider this treatment option in patients with AF refractory to DC cardioversion.     

Incidence and modes of onset of early reinitiation of atrial fibrillation after successful internal cardioversion, and its prevention by intravenous sotalol

OBJECTIVES—To study the incidence and mode of onset of early reinitiation of atrial fibrillation (ERAF) following successful internal cardioversion of chronic atrial fibrillation, and to determine the effects of sotalol in the prevention of ERAF.
DESIGN—The incidence and modes of onset of ERAF and the acute effects of intravenous sotalol in the prevention of ERAF were studied retrospectively.
SETTING—Electrophysiology laboratory at a university teaching hospital.
PATIENTS—64 patients, mean (SD) age 62 (10) years, who underwent internal cardioversion of chronic atrial fibrillation (mean duration of atrial fibrillation 31 (39) months).
MAIN OUTCOME MEASURES—ECGs and intracardiac electrograms recorded during the internal cardioversion of atrial fibrillation using 3/3 ms biphasic, R wave synchronised shocks.
RESULTS—52 patients (81%) had successful electrical cardioversion, and 20 (31%) of these had ERAF during the procedure. There was no clinical predictor for the occurrence of ERAF. Fifty eight episodes of ERAF were observed. Five ERAF episodes (9%) had preceding bradycardia and 53 (91%) of these were triggered by atrial premature beats with normal preceding heart rate. Atrial premature beats that reinitiated atrial fibrillation had a shorter coupling interval (333 (43) ms v 396 (100), p < 0.001) and a lower prematurity index (0.44 (0.11) v 0.55 (0.14), p < 0.001) than those that did not reinitiate atrial fibrillation. Repeated shock delivery and increasing the defibrillation energy did not prevent ERAF. Intravenous sotalol infusion decreased the numbers of atrial premature beats and prolonged their coupling interval, and prevented ERAF after repeated defibrillation in 83% of patients with ERAF.
CONCLUSIONS—ERAF is a significant clinical problem after successful internal cardioversion of chronic atrial fibrillation, and was observed in up to 31% of patients. In most episodes, ERAF was triggered by short coupling atrial premature beats with preceding normal heart rate. Intravenous sotalol was effective in preventing ERAF in most cases.


Keywords: atrial fibrillation; low energy cardioversion; sotalol     

Factors predicting success rate and recurrence of atrial fibrillation after first electrical cardioversion in patients with persistent atrial fibrillation

BACKGROUND: The recurrence rate of atrial fibrillation (AF) after elective cardioversion is high. HYPOTHESIS: The study aimed to identify clinical predictors for successful electrical cardioversion and maintenance of sinus rhythm after a first electrical cardioversion in patients with persistent AF without concomitant antiarrhythmic drugs of class I and III. METHODS: Consecutive outpatients (n = 166) with persistent AF for > 1 month, scheduled for elective cardioversion, were prospectively included in the study. A clinical investigation, echocardiographic assay, and Holter electrocardiogram (ECG) before and ECG 4 weeks after cardioversion, were performed in all patients. RESULTS: The mean age of the patients was 68 years (range 45-83) and duration of AF was 5 (1-48) months. Sinus rhythm was established in 124 (75%) patients. In multivariate analysis, only duration of AF < 6 months (p < 0.04, odds ratio [OR] 2.2, 95% confidence interval [CI] 1.1 to 4.7) and patients weight (p < 0.03, OR 2.3, 95% CI 1.1 to 4.8 for weight < 80 kg) were identified as independent predictors of successful cardioversion. At 4 weeks after cardioversion, only 46 (37%) of 124 patients maintained sinus rhythm. Independent factors for maintenance of sinus rhythm, in multivariate analysis, were AF <3 months (p < 0.04, OR 2.5, 95% CI 1.1 to 5.6), treatment with beta blockers (p < 0.00001, OR 7.0, 95% CI 3.0 to 16.3) or verapamil/diltiazem (p < 0.04, OR 3.6, 95% CI 1.1 to 12.1), and right atrial dimension < 37 mm (p < 0.02, OR 5.9, 95% CI 1.4 to 25.4). CONCLUSIONS: In patients with persistent AF, the patient's weight and the duration of AF are independent predictors for a successful cardioversion. Short duration of AF, treatment with beta blockers or verapamil/diltiazem, and right atrial area/dimension are independent predictors for maintenance of sinus rhythm.     

Plasma levels of NT-pro-BNP in patients with atrial fibrillation before and after electrical cardioversion

Summary Objective Plasma levels of brain natriuretic peptide (BNP) have been examined in studies on patients with persistent atrial fibrillation, both before and after electrical cardioversion. Studied patients often showed a comorbidity with congestive heart failure, which complicates interpretation of measured BNP values as a natriuretic peptide. The aim of this study was to examine plasma levels of N-terminal fragment pro-brain natriuretic peptide (NT-pro-BNP), which is the more stable but inactive cleavage product of pro-BNP in patients with atrial fibrillation, but normal left ventricular ejection fraction, before and after electrical cardioversion. Patients and methods NT-pro-BNP plasma levels of 34 consecutive patients were measured before, shortly after and 11 days after electrical cardioversion. All patients showed a normal ejection fraction after echocardiographic or laevocardiographic criteria. Results At baseline, all patients showed elevated NT-pro-BNP compared to a healthy control group (1086 vs. 66.9 pg/ml, p<0.001). After a mean follow-up time of 11 days in patients with persistent restored sinusrhythm, NT-pro-BNP decreased from 1071 pg/ml at baseline to 300 pg/ml (p<0.001). In contrast, patients with recurrence of atrial fibrillation showed increased levels from 1570.5 pg/ml at baseline to 1991 pg/ml (p=0.13; n.s.). Recurrence of atrial fibrillation was independent from height of NT-pro-BNP levels at baseline (p=0.23). Conclusions Atrial fibrillation in patients with a normal left ventricular ejection fraction is associated with elevated NT-pro-BNP plasma levels, which decrease when a persistent sinus-rhythm can be restored by electrical cardioversion. On the other hand, NT-pro-BNP seems to increase (n.s.) when recurrence of atrial fibrillation occurs. Finally, NT-pro-BNP is no valid predictor for long-term success of sinus-rhythm restoration by electrical cardioversion.      

Predictors for maintenance of sinus rhythm after cardioversion in patients with nonvalvular atrial fibrillation

Recurrence of atrial fibrillation (AF) after cardioversion (CV) to sinus rhythm (SR) is determined by various clinical and echocardiographic parameters. Transesophageal echocardiographic (TEE) parameters have been the focus of clinicians' interests for restoring and maintaining SR. This study determined the clinical, transthoracic, and TEE parameters that predict maintenance of SR in patients with nonvalvular AF after CV. We enrolled 173 patients with nonvalvular AF in the study. TEE could not be performed in 26 patients prior to CV. Twenty-five patients had spontaneously CV prior to TEE. Six patients were excluded because of left atrial (LA) thrombus assessed by TEE. CV was unsuccessful in 6 patients. The remaining 110 consecutive patients (56 men, 54 women, mean age 69 +/- 9 years), who had been successfully cardioverted to SR, were prospectively included in the study. Fifty-seven (52%) patients were still in SR 6 months after CV. Age, gender, the configuration of the fibrillation wave on the electrocardiogram, pulmonary venous diastolic flow, and the presence of diabetes, hypertension, coronary artery disease, mitral annulus calcification, and mitral valve prolapse (MVP) did not predict recurrence. Duration of AF, presence of chronic obstructive pulmonary disease (COPD), LA diameter, left ventricular ejection fraction (EF), left atrial appendage peak flow (LAAPF), LAA ejection fraction (LAAEF), pulmonary venous systolic flow (PVSF), and the presence of LA spontaneous echo contrast (LASEC) predicted recurrence of AF 6 months after CV. In multivariate analysis, LAAEF < 30% was found to be the only independent variable (P < 0.0012) predicting recurrence at 6 months after CV in patients with nonvalvular AF. LAAEF more than 30% had a sensitivity of 75% and a specificity of 88% in predicting maintenance of SR 6 months after CV in patients with nonvalvular AF. In conclusion, TEE variables often used to determine thromboembolic risk also might be used to predict the outcome of CV.     

心房颤动患者复律后心房顿抑与脑利钠肽的研究

目的:通过对心房颤动(房颤)患者复律后心房超声检查及血浆脑利钠肽(BNP)的检测,探讨心房顿抑与BNP的关系。方法:将76例房颤患者分为阵发性房颤组(40例)和持续性房颤组(36例),另入选对照组患者20例。在房颤复律后2h、1d、1周和1个月时经胸壁超声心动图(TTE)检查测定舒张晚期血流速度(A峰)和心房充盈分数(AFF),以A峰<50cm/s作为心房顿抑的标准,并测定上述时间点及复律前血浆BNP。结果:阵发性房颤组复律后2h心房顿抑的发生率为45.0%,复律后A峰和AFF至1周时恢复正常;持续性房颤组复律后2h左房顿抑的发生率为61.6%,A峰和AFF至1个月时恢复正常。2组复律后1d和1周时BNP与A峰有显著的相关性,在房颤复律后1d和1周时仍然存在心房顿抑的患者BNP显著高于无顿抑发生的患者(P<0.01),心房顿抑消失后,BNP迅速下降。结论:房颤复律后1d和1周时血浆BNP水平与跨二尖瓣A峰有相关性,较高的血浆BNP可能提示心房顿抑的持续存在,有助于了解左心房功能恢复情况。     

Successful external cardioversion of atrial fibrillation in patients referred to an electrophysiologist for internal cardioversion.

BACKGROUND: Internal cardioversion of atrial fibrillation with direct current energy has become an increasingly employed technique for patients who fail external cardioversion. HYPOTHESIS: The purpose of this study was to determine whether internal cardioversion could be avoided by careful attention to cardioversion technique in a group of patients referred specifically for internal cardioversion after failed external cardioversion by community cardiologists. METHODS: We performed external cardioversion utilizing two operators applying significant pressure to the thorax with up to 360 J prior to the planned internal cardioversion in 20 patients referred for internal cardioversion after failed attempts at external cardioversion. RESULTS: Sixteen patients (80%) were successfully cardioverted and avoided the risk, inconvenience, and cost of internal cardioversion. CONCLUSION: External cardioversion with significant anterior paddle pressure by two operators can decrease the need for internal cardioversion in a significant portion of patients referred to electrophysiologists for internal cardioversion and should be considered prior to an invasive procedure.     

胺碘酮与索他洛尔治疗心房颤动的Meta分析

目的 评价胺碘酮和索他洛尔治疗心房颤动（房颤）的有效性和安全性.方法 计算机检索Cochrane图书馆、PubMed、EMBASE、CBM、CNKI、VIP等数据库,并辅以Google Scholar等检索,收集有关胺碘酮和索他洛尔对比治疗房颤的随机对照试验（RCT）,由2名参与者独立评价纳入研究质量、提取资料,对两药房颤转复率、复发率及不良反应采用RevMan 5.0软件进行Meta分析.结果 共纳入14个RCT（1 508例患者）;Meta分析结果显示胺碘酮与索他洛尔房颤转复率及不良反应无统计学差异,胺碘酮防止房颤复发作用优于索他洛尔（比数比=0.49,95%可信区间为0.31～0.75,P=0.001）.结论 胺碘酮与索他洛尔在小剂量范围内均较为安全,前者降低房颤复发率效果较好.     

Rapid formation of left atrial appendage thrombus after unsuccessful cardioversion of atrial fibrillation

The acute effect of failed attempts of cardioversion on left atrial (LA) and left atrial appendage (LAA) functions are generally considered benign and no adverse effects have been reported. We report on a subject who had rapid formation of a fresh, mobile thrombus in the LAA despite unsuccessful cardioversion and therapeutic anticoagulation.     

Prevalence and significance of focal sources of atrial arrhythmia in patients undergoing cardioversion of persistent atrial fibrillation

INTRODUCTION: Recent reports have high-lighted the importance of focal atrial arrhythmias as a curable cause for a group of patients with frequently recurrent paroxysmal atrial fibrillation (AF). The importance of this arrhythmia mechanism in the general population of patients with persistent AF is unknown. METHODS AND RESULTS: After successful internal cardioversion of 50 consecutive patients with persistent AF (mean age 60 years, mean duration of AF 26 months), endocardial activity in the immediate postcardioversion period was analyzed for the presence of focal atrial activity. Postcardioversion atrial arrhythmias were considered to be focal if there was evidence of a localized source of repetitive early atrial activation, either in the form of (1) self-terminating monomorphic atrial tachycardia (at least five beats) or (2) recurrences of AF with an initial atrial activation sequence (first five beats) that was both monomorphic and reproducible with repeated recurrences. Evidence for a focal atrial arrhythmia was present in 20 of the total group of 50 patients (40%). Multivariate analysis of clinical characteristics revealed the diagnosis of lone AF as the only independent predictor of a focal source of AF (P = 0.028). Thirty-nine patients were discharged from hospital in sinus rhythm. At 1-month follow-up, 25 (64%) of these 39 patients had suffered AF recurrence. The only significant predictor of AF recurrence was evidence of a focal source of atrial arrhythmia immediately after cardioversion, with a relative risk of 1.73 (range 1.1 to 2.7; P = 0.015). CONCLUSION: Focal atrial arrhythmias are common in patients presenting with "idiopathic" persistent AF, suggesting a possible causative role in the generation of this common arrhythmia.     

Temporal changes in atrial refractoriness following DC cardioversion of persistent atrial fibrillation in man.

AIMS: Studies have demonstrated shortening of the atrial effective refractory period (ERP) after episodes of atrial fibrillation (AF). This is termed atrial remodelling. It is unclear whether restoration of SR after persistent AF in patients with a clinical substrate results in reversal of this shortening and whether this is maintained long term. METHODS AND RESULTS: The ERP was determined at mid-lateral right atrial wall (MLRA) and right atrial appendage (RAA) at 600 ms and 400 ms drive cycle lengths and at basic sinus cycle length in 81 patients with persistent AF immediately, 24 h and 2 weeks following external DC cardioversion. All atrially active drugs were stopped for at least 5 half lives. (1) Prolongation of the ERP was observed at both atrial sites and all cycle lengths up to 24 h post cardioversion (p < 0.0001). (2) However, between 24 h and 2 weeks a subsequent shortening occurred in the ERP returning it to near post cardioversion levels. (3) The ERP was significantly longer at 24 h post cardioversion in patients who remained in SR for 2 weeks or longer compared with those who reverted to AF. CONCLUSION: Prolongation of the atrial ERP occurred following restoration of SR in persistent AF patients but was not maintained and displayed a biphasic pattern such that by 2 weeks the ERP had returned to baseline values. Despite this finding, a longer ERP at 24 h post cardioversion was associated with maintenance of SR in the medium-term.     

Transesophageal echocardiography-guided cardioversion of atrial fibrillation

Transesophageal echocardiography-guided anticoagulation management of patients with atrial fibrillation undergoing cardioversion has evolved over the past decade as a viable alternative to conventional anticoagulation management. Its use grew out of a need for a more predictable, dependable, and convenient approach to this difficult management dilemma, which has become increasingly prevalent in practice as an increasing number of patients present to clinics and hospitals with atrial fibrillation. In addition to its use in risk stratification of patients scheduled to undergo cardioversion, this management strategy allows for early cardioversion, which enables a minimal delay in proceeding from the diagnosis to the institution of therapy (electrical cardioversion). This review explores the evolution of the transesophageal echocardiography-guided strategy, the advantages and disadvantages of its use, and possible modifications to the strategy that would allow for a more convenient, practical, and more widely acceptable approach in the near future.     

氯沙坦联合胺碘酮对阵发性心房颤动复律及复律后窦性心律维持的影响

目的 了解氯沙坦联合胺碘酮对阵发性心房颤动的复律效果及复律后窦性心律维持的影响.方法 2003年1月至2005年10月将解放军421医院心内科86例非瓣膜病阵发性心房颤动患者分为胺碘酮治疗组和氯沙坦 胺碘酮治疗组,观察治疗24 h,3 d和7 d时心房颤动的转复情况.在心房颤动复律后,继续药物治疗并随访观察1年,评价两组窦性心律的维持效果.结果 胺碘酮组44例心房颤动患者治疗24 h,3 d和7 d心房颤动的转复率分别为65.90%,75.00%和86.36%,氯沙坦 胺碘酮治疗组的转复率为66.66%,80.95%和95.23%.两组在7 d时心房颤动的转复率差异有显著性意义(P＜0.05).随访1年时两组窦性心律的维持率分别为71.05%和87.50%(P＜0.05),两组左房内径分别为(37.45±1.44)mm和(35.83±1.38)mm(P＜0.05).结论 氯沙坦联合胺碘酮对阵发性心房颤动的复律及复律后窦性心律维持均优于单用胺碘酮治疗,可能与氯沙坦抑制肾素-血管紧张素系统,降低心脏负荷,抑制心房电及结构重构有关.     

经皮球囊二尖瓣成形术后心房颤动复律患者血浆中利钠肽和脑钠肽的变化

目的:观察经皮球囊二尖瓣成形术(PBMV)后心房颤动(房颤)成功复律与未复律患者血浆中心房利钠肽(ANP)和脑钠肽(BNP)的变化,并探讨与血流动力学参数的关系.方法:选择成功PBMV的风湿性二尖瓣狭窄伴持续房颤律患者48例,其中成功复律组20例,未复律28例,获得外周静脉血及血流动力学完整资料.分别用放射免疫法和酶链免疫法测定血浆中ANP、BNP值,由超声心动图测左房内径(LAD)、二尖瓣口面积(MVA)、二尖瓣跨瓣压差(MPG)、左室舒张末径(LVEED).结果:随访至PBMV后1年,复律组患者血浆中ANP和BNP逐步下降,而未复律组BNP呈下降趋势,但差异无统计学意义(P>0.05), 复律组LAD和MPG较未复律组显著缩小(P<0.05).ANP、BNP与血流动力学指标之间相关性比较显示:复律组,术后1年与术前比较△LAD与△ANP下降仍呈正相关性(r=0.774;P<0.05),而△BNP与△MPG有相关(r=0.574;P<0.05).结论:PBMV后,房颤复律可进一步改善血流动力学,缩小LAD,降低血浆中ANP和BNP水平,复律后ANP和BNP的变化,仍是间接反映LAD和MPG变化趋势的有效指标.     

Amiodarone in restoration and maintenance of sinus rhythm in patients with chronic atrial fibrillation after unsuccessful direct-current cardioversion

Background: When direct-current (DC) cardioversion is used, sinus rhythm can be restored, at least temporarily, in 80–90% of patients with atrial fibrillation. However, there is a small but significant group of patients with chronic atrial fibrillation in whom DC cardioversion has failed to restore sinus rhythm. The value of antiarrhythmic drug pretreatment before DC cardioversion is still controversial. Hypothesis: The aim of our study was to assess (1) the effecti veness of repeat DC cardioversion in patients with chronic atrial fibrillation after pretreatment with amiodarone, and (2) the efficacy of amiodarone in maintaining sinus rhythm after repeat cardioversion. Methods: Forty-nine patients with chronic atrial fibrillation after ineffective DC cardioversion were included in the study. Repeat DC cardioversion was performed after loading with oral amiodarone, 10–15 mg/kg body weight/day for a period necessary to achieve the cumulative dose of over 6.0 g. Results: Spontaneous conversion to sinus rhythm during amiodarone pretreatment was achieved in 9 of 49 patients (18%). Direct-current cardioversion was performed in 39 patients and sinus rhythm was achieved in 23 of these patients (59%). Mean heart rate decreased from 95 beats/min before to 68 beats/min after DC cardioversion (p<0.001). Systolic blood pressure significantly (p<0.05) decreased from 126 ± 23 to 108 ± 25 mmHg. Complications occurring in four patients just after electroconversion were well tolerated and of short duration. After 12 months, 52% of patients maintained sinus rhythm on low dose (200 mg/day) amiodarone therapy. Conclusion: Pretreatment with amiodarone and repeat DC cardioversion allows for restoration of sinus rhythm in about 65% of patients with chronic atrial fibrillation after first ineffective DC cardioversion. Direct-current cardioversion can be performed safely with the use of standard precautions in patients who are receiving amiodarone. At 12 months' follow-up, more than 50% of patients maintain sinus rhythm on low-dose amiodarone after successful repeat cardioversion.     

Lack of prevention of heart failure by serial electrical cardioversion in patients with persistent atrial fibrillation

OBJECTIVE—To investigate the occurrence of heart failure complications, and to identify variables that predict heart failure in patients with (recurrent) persistent atrial fibrillation, treated aggressively with serial electrical cardioversion and antiarrhythmic drugs to maintain sinus rhythm.DESIGN—Non-randomised controlled trial; cohort; case series; mean (SD) follow up duration 3.4 (1.6) years.SETTING—Tertiary care centre.SUBJECTS—Consecutive sampling of 342 patients with persistent atrial fibrillation (defined as > 24 hours duration) considered eligible for electrical cardioversion.INTERVENTIONS—Serial electrical cardioversions and serial antiarrhythmic drug treatment, after identification and treatment of underlying cardiovascular disease.MAIN OUTCOME MEASURES—heart failure complications: development or progression of heart failure requiring the institution or addition of drug treatment, hospital admission, or death from heart failure.RESULTS—Development or progression of heart failure occurred in 38 patients (11%), and 22 patients (6%) died from heart failure. These complications were related to the presence of coronary artery disease (p < 0.001, risk ratio 3.2, 95% confidence interval (CI) 1.6 to 6.5), rheumatic heart disease (p < 0.001, risk ratio 5.0, 95% CI 2.4 to 10.2), cardiomyopathy (p < 0.001, risk ratio 5.0, 95% CI 2.0 to 12.4), atrial fibrillation for < 3 months (p = 0.04, risk ratio 2.0, 95% CI 1.0 to 3.7), and poor exercise tolerance (New York Heart Association class III at inclusion, p < 0.001, risk ratio 3.5, 95% CI 1.9 to 6.7). No heart failure complications were observed in patients with lone atrial fibrillation.CONCLUSIONS—Aggressive serial electrical cardioversion does not prevent heart failure complications in patients with persistent atrial fibrillation. These complications are predominantly observed in patients with more severe underlying cardiovascular disease. Randomised comparison with rate control treatment is needed to define the optimal treatment for persistent atrial fibrillation in relation to heart failure.     

Effect of atrial fibrillation duration on probability of immediate recurrence after transthoracic cardioversion

INTRODUCTION: An immediate recurrence of atrial fibrillation (IRAF) appears to be more common after early restoration of sinus rhythm with an implantable atrial defibrillator than after elective transthoracic cardioversion, which suggests that the probability of IRAF may be related to the duration of AF. METHODS AND RESULTS: Transthoracic cardioversion was performed 85 +/- 187 days (range 7 minutes to 8 years) after the onset of atrial fibrillation in 315 patients (mean age 61 +/- 13 years). IRAF was defined as a recurrence of AF within 60 seconds after restoration of sinus rhythm. IRAF occurred in 56% of patients when cardioversion was performed within 1 hour of the onset of AF compared with 12% of patients when cardioversion was performed after 24 hours of AF (P < 0.001). The duration of AF was the only independent predictor of IRAF among the clinical variables of age, gender, structural heart disease, antiarrhythmic drug therapy, and cardioversion energy (P < 0.01). CONCLUSION: IRAF is more likely to occur when the duration of AF is <1 hour than when the duration is >24 hours. This observation has clinical implications for the most appropriate timing of cardioversion, particularly in patients who receive device therapy for AF.     

Clinical value of left atrial appendage flow velocity for predicting of cardioversion success in patients with non-valvular atrial fibrillation.

BACKGROUND: Echocardiographic parameters for predicting cardioversion outcome in patients with non-valvular atrial fibrillation are not accurately defined. OBJECTIVE: To evaluate the role of left atrial appendage flow velocity detected by transoesophageal echocardiography for prediction of cardioversion outcome in patients with non-valvular atrial fibrillation enrolled in a prospective. multicentre, international study. METHODS: Four hundred and eight patients (257 males, mean age: 66 +/- 10 years) with non-valvular atrial fibrillation lasting more than 48 h but less than 1 year underwent transthoracic echocardiography and transoesophageal echocardiography before either electrical (n=324) or pharmacological (n=84) cardioversion. RESULTS: Cardioversion was successful in restoring sinus rhythm in 328 (80%) and unsuccessful in 80 patients (20%). Mean left atrial appendage peak emptying flow velocity was significantly higher in patients with successful than in those with unsuccessful cardioversion (32.4 +/- 17.7 vs 23.5 +/- 13.6 cm x s(-1); P<0.0001). At multivariate logistic regression analysis, three parameters proved to be independent predictors of cardioversion success: the atrial fibrillation duration <2 weeks (P=0.011, OR=4.9, CI 95%=1.9-12.7), the mean left atrial appendage flow velocity >31 cm x s(-1) (P=0.0013, OR=2.8, CI 95%=1.5-5.4) and the left atrial diameter <47 mm (P=0.093, OR=2.0, CI 95%=1.2-3.4). These independent predictors of cardioversion success outperformed other univariate predictors such as left ventricular end-diastolic diameter <58 mm, ejection fraction >56% and the absence of left atrial spontaneous echo contrast. CONCLUSION: In patients with non-valvular atrial fibrillation, measurement of the left atrial appendage flow velocity profile by transoesophageal echocardiography before cardioversion provides valuable information for prediction of cardioversion outcome.     

Impact of biphasic electrical cardioversion of atrial fibrillation on early recurrent atrial fibrillation and shock efficacy

INTRODUCTION: Early recurrent atrial fibrillation (ERAF) after external cardioversion of atrial fibrillation (AF) occurs in 12% to 26% of patients. Whether biphasic cardioversion has an impact on the incidence of ERAF after cardioversion of AF is unclear. METHODS AND RESULTS: Consecutive patients (n = 216, mean age 66 years, 71% male, 88% with structural cardiovascular disease or hypertension) underwent cardioversion with a biphasic (Bi) or monophasic (Mo) shock waveform in randomized fashion. Energies used were 120-150-200-200 Ws (Bi) or 200-300-360-360 Ws (Mo). The two study groups (Bi vs Mo) did not differ with regard to age, sex, body mass index, underlying cardiovascular disease, left atrial diameter, left ventricular ejection fraction, duration of AF fibrillation, and antiarrhythmic drug therapy. Mean delivered energy was significantly lower in the Bi group (Bi: 186 +/- 143 Ws vs Mo: 324 +/- 227 Ws; P < 0.001). Overall incidence of ERAF (AF relapse within 1 minute after successful cardioversion) was 8.9% and showed no difference between the two groups (Bi: 8.1% vs Mo: 9.7%, P = NS). Cardioversion was successful in 95.4% of patients. The success rate was comparable in both groups (Bi: 94.3% vs Mo 96.8%; P = NS). First shock efficacy did not differ between Bi and Mo (76.4% vs 67.7%; P = NS). Mean number of shocks were 1.4 shocks per patient in both groups. CONCLUSION: Biphasic cardioversion allows comparable success rates with significantly lower energies. However, the incidence of ERAF is not influenced by biphasic cardioversion. With the energies used, biphasic and monophasic shock waveforms are comparable with regard to first shock and cumulative shock efficacy.