Lone atrial fibrillation: influence of familial disease on gender predilection

Introduction: Epidemiological studies report a male predominance in lone atrial fibrillation (LAF). Phenotypic differences between sporadic and familial LAF could aid in deciding which cases should undergo family screening. We sought to determine gender distribution in sporadic and familial LAF, gender-based differences, and phenotypic differences between sporadic and familial LAF.
Methods: Since November 2000, 192 unrelated LAF probands were recruited. Sporadic LAF was defined as the absence of a family history of LAF. Familial LAF was classified as possible if one first- or second-degree relative had LAF, or confirmed if ≥ 2 relatives had LAF. Affected relatives (n = 87) of 34 confirmed familial probands were also evaluated. For unrelated LAF probands, differences in proportions and means were tested using χ² and ANOVA, respectively. Difference in gender ratio among the family history groups was tested using mixed models.
Results: Male proportion was greater among sporadic (82%) and possible familial probands (84%) than confirmed familial probands (62%), and affected relatives (54%), P < 0.001. Sporadic LAF was more common in men (62%) than women (51%), P = 0.03. More women were affected by palpitation and nocturnal symptoms than men. More patients had permanent AF in the confirmed familial group (27%), compared with the possible familial (7%) and the sporadic LAF group (8%), P = 0.05, but no other phenotypic discriminators were identified.
Conclusions: Male predilection for LAF is attenuated as the likelihood of dominant Mendelian inheritance increases. Increased frequency of "sporadic" LAF among men could be partially due to X-linked recessive inheritance. Finally, sporadic and familial LAF are clinically indistinguishable.     

孤立性房颤的临床特征及亚型分析

目的通过病例分析研究，总结孤立性房颤的临床亚型。方法对69例孤立性房颤进行询问病史，全面体格检查以及心电图、动态心电图、超声心动图等严格检出和控制人选研究对象，对所获临床资料进行统计分析。结果研究对象91．3％为阵发房颤，15．9％为永久性房颤；房颤睡眠中发作占43．2％，运动后发作47．5％，餐后发作28．6％等。有房颤家族史27．5％。结论孤立性房颤的临床亚型可分为睡眠发作型、运动诱发型和餐后发作型，部分孤立性房颤患者具有家族遗传性     

心脏转录因子GATA4与心房颤动的关系

心脏转录因子GATA4是一种在心脏中大量表达的锌指转录因子,在心血管发育、心肌重构与肌细胞凋亡方面发挥着重要的生理作用,GATA4基因突变可导致多种先天性心脏病。近年来的研究显示,GATA4基因突变也可导致心房颤动（AF）。本文拟就GATA4的生理功能及其与AF的关系进行综述,旨在便于理解AF新的分子机制,从而有助于AF的早期预防和个体化治疗。     

New-onset atrial fibrillation

Patients with new-onset atrial fibrillation are often hospitalized emergently. To determine whether this is necessary, the authors retrospectively reviewed the care of 97 consecutive patients with this illness. No reason for the atrial fibrillation in 43 patients could be identified. Hypertension, coronary artery disease, and valvular heart disease were the most commonly associated conditions; myocardial infarction occurred in one patient. In 82% of patients, atrial fibrillation reverted to normal sinus rhythm during hospitalization. Three patients needed emergent hospitalization irrespective of the presence of atrial fibrillation. In the remainder, admission was based solely on the diagnosis of new-onset atrial fibrillation. Ninety-eight per cent had an uncomplicated hospital course. It is concluded that hospitalization is not necessary for all patients with new-onset atrial fibrillation. Those in whom reversion to normal sinus rhythm occurs rapidly during digoxin therapy can be discharged. Where no major medical illness is evident patients can be admitted to a bed outside the intensive care unit until reversion to normal sinus rhythm or rate control is achieved. Received from the Department of Medicine, North Shore University Hospital, Manhasset, New York, and the Departments of Medicine and Pharmacology, Cornell University Medical College, New York, New York. Supported in part by a grant from the Pharmaceutical Manufacturers Association Foundation.     

Initiation of ventricular fibrillation by atrial fibrillation

We report the case of a patient who developed spontaneouslya ventricular fibrillation during atrial fibrillation, 8 minafter a perfusion of isoproterenol was stopped Two mechanismscould explain the ventricular arrhythmia: silent ischaemia anda long-short cycle sequence just before ventricular fibrillation.     

持续性心房颤动患者无症状心房颤动的发生情况及影响因素

目的 分析持续性心房颤动(房颤)患者中无症状房颤的发生情况及影响因素.方法 收集经24 h动态心电图监测确诊的持续性房颤患者82例,观察症状的有无及发生比例.经抗心律失常药物治疗3个月后复查24 h动态心电图监测,观察症状的变化情况.采用多无logistic回归分析持续性房颤症状与临床特征的相关性.结果 82例患者中34例(42%)无症状房颤发作,48例有症状房颤发作.应用抗心律失常药物治疗3个月后,48例有症状患者中31例症状完全消失,其中4例转复为窦性心律,27例为无症状房颤发作.34例无症状患者中,5例转复为窦性心律,24例仍为无症状房颤发作.持续性房颤中有症状和无症状患者年龄,瓣膜病比较差异有统计学意义(P＜0.05).其症状与瓣膜病呈正相关(b=1.959,P=0.001),与年龄呈负相关(b=-0.837,P=0.032).结论 持续性房颤患者中无症状房颤的发生率较高.抗心律失常药物既可减少房颤发作,又可减少房颤症状.高龄和非瓣膜病房颤患者易发生无症状房颤.     

Familial atrial fibrillation with fetal onset

A woman presented during two pregnancies (at 25 and 23 weeks' gestation, respectively) because the fetuses had rapid, irregular tachycardia and hydrops. After maternal drug treatment and achievement of slower fetal heart rates, the hydrops gradually resolved. Both babies were born full term with continuing atrial fibrillation. In the first, an ectopic atrial rhythm was temporarily achieved during high dose flecainide treatment but, in the younger sibling, all medications and repeated cardioversions failed even temporarily to convert the atrial fibrillation with an almost isoelectric baseline in ECG to sinus rhythm. Good rate control has been achieved with digoxin in both patients. No infective, immunological, or structural cause was found in either case, and thus an inherited aetiology is probable.

Keywords: atrial fibrillation; arrhythmias; fetal atrial fibrillation; familial arrhythmias     

Genetics polymorphisms and atrial fibrillation susceptibility: a systematic review and meta-analysis

Background Atrial fibrillation (AF) was used to be considered as nongenetics disorder, but recent studies have revealed that genetics variants conferred susceptibility to AF development, but most with limited evidence. In order to systematically evaluate the overall contributions of gene-disease association studies to current understandings of the genetic susceptibility to atrial fibrillation, we perform a systematic review and meta-analysis based on comprehensive searches. Method All studies on the associa...     

左房异常与心房颤动的关系

目的探讨左房异常与心房颤动发生的关系。方法应用心电图和动态心电图进行,持续性房颤患者为A组,阵发性房颤、房扑患者为B组,仅有心电图P波增宽的患者为C组,A、B、C三组各40例。所有入选患者均经超声心动图检测左房大小,观察患者窦性心律时心电图P波时限、切迹和P波离散度,并分析与房颤发生的关系。结果房颤男性多于女性,年龄大于60岁者94例(占78.3%),三组中86.7%的患者存在器质性心脏病(104例)。心电图P波切迹明显、P波离散度大者快速房颤发生率高;超声心动图检测左房直径大者房颤发生率高,持续性房颤比阵发性房颤患者左房直径大(p<0.05)。结论左房扩大、房内阻滞及P波离散度增大的患者易发生房颤。     

Update on atrial fibrillation: part II

Antiarrhythmic drugs are an essential tool in the management of atrial fibrillation (AF). Although we are already on the threshold of a large expansion in the use of ablation therapies, these will not, however, be appropriate for all patients, and pharmacological therapies will continue to have an important place in the management of atrial fibrillation. The plethora of antiarrhythmic drugs currently available for the treatment of atrial fibrillation is a reflection that none is wholly satisfactory, each having limited efficacy combined with poor safety and tolerability. Improved class III antiarrhythmic drugs, such as dronedarone, new classes of antiarrhythmic agents, such as atrial repolarization delaying agents, and upstream therapies dealing with substrate, represent potential sources of new pharmacological therapies.     

心房颤动的家谱分析

目的：探讨心房颤动发病的遗传性。方法：对13例心房颤动进行家谱调查，每个家谱进行3－4代人调查，调查包括对房颤患者进行心电图、心动超声图第一系列检查，其中一部分家庭成员采血进行了DNA分析。结果：本组房颤均于40岁以后（年龄45－81岁）发病，房颤包括持续性与阵发性房颤。除1例外，男性房颤均有10年以上的吸烟史，第1家谱中；第二代有4例房颤患者，第8、10个家谱中第二代分别各有3例房颤。结论：本组房颤均于成年发病，房颤病例见于2－3代发病，推测部分房颤的发病病因与基因有关，尚待进一步扩大病例深入研究。     

New method of determining the atrial fibrillation cycle length during human atrial fibrillation

INTRODUCTION: The aim of this study was to investigate the usefulness of the autocorrelation function (reversed fast Fourier transform analysis) in determining the atrial fibrillation cycle length (AFCL) during human atrial fibrillation (AF). METHODS AND RESULTS: From 30 episodes of atrial electrograms recorded for 30 seconds from the high right atrium during type I AF in 16 patients, the mean, 5th percentile (p5), and 95th percentile (p95) of the AFCLs were measured by using a computer-picked activation time. The peak, minimum, and maximum AFCLs also were measured by using the autocorrelation function. The mean AFCL was retrieved at the point of the maximum peak of the coefficient of the first positive autocorrelogram. The minimum AFCL (min AFCL) was chosen as the point where the first positive autocorrelogram crossed the baseline from negative to positive, and the maximum AFCL (max AFCL) was chosen as the point where the first positive autocorrelogram crossed the baseline from positive to negative. There was a significantly strong correlation between the mean and peak AFCLs (r = 0.995, P < 0.0001), p5 and min AFCLs (r = 0.953, P < 0.0001), and p95 and max AFCLs (r = 0.98, P < 0.0001). CONCLUSION: The autocorrelation function was useful in determining the AFCLs, at least during type I AF. The min AFCL may be used as an index of the refractory period during AF when the p5 AFCL approximates the refractory period.     

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.     

Electrocardiographic differentiation of atrial flutter from atrial fibrillation by physicians

The purpose of this study was to determine the ability of physicians to differentiate atrial flutter from atrial fibrillation on a surface electrocardiogram (ECG). A questionnaire containing three 12-lead ECGs was mailed to 689 physicians, with multiple-choice questions asking whether the rhythm on each ECG was atrial flutter or atrial fibrillation. ECG 1 showed atrial fibrillation with prominent atrial activity (>0.2 mV) in lead V1; ECG 2 displayed atrial fibrillation with prominent atrial activity (>0.2 mV) in leads III and V1; and ECG 3 displayed atrial flutter. Overall, ECG1 was correctly identified as atrial fibrillation by 79% of physicians, ECG 2 was correctly identified as atrial fibrillation by 31%, and ECG 3 was correctly identified as atrial flutter by 90%. Cardiology fellows and cardiologists correctly identified ECG 1 more often than house officers and internists (95% vs 63%; P < or = .01). ECG 2 was correctly identified by 26% of cardiology fellows and cardiologists and by 37% of house officers and internists (P = .10). ECG 3 was correctly identified by 91% of cardiology fellows and cardiologists and by 82% of house officers and internists (P = .06). In conclusion, atrial fibrillation is frequently misdiagnosed as atrial flutter. Misdiagnosis of atrial fibrillation occurs more often when atrial activity is prominent on an ECG in more than one lead.     

瓣膜置换、房颤射频消融术治疗房颤的临床护理研究

目的：分析探讨瓣膜置换 房颤射频消融术治疗房颤患者的临床护理方法与效果。方法：选择我院2014年1月-2014年12月之间收治的行瓣膜置换 房颤射频消融术治疗的36例患者作为观察对象,采用随机的方式将其分为观察组和对照组各18例。对照组患者采取常规的护理干预;观察组患者应用系统护理方法。分析对比两组患者的临床治疗效果及患者满意度。结果：观察组患者术后出现并发症的比例小于对照组,差异具有统计学意义(P＜0.05);同时观察组患者对护理服务的满意度显著高于对照组,差异同样具有统计学意义(P＜0.05)。结论：对瓣膜置换 房颤射频消融术治疗房颤患者应用系统的护理干预具有很好的改善效果,构建和谐的护患关系,值得在临床中推广。     

Occam's razor and the unraveling of atrial fibrillation

The search for a mechanism to explain atrial fibrillation (AF) has lasted for over a century and continues. Significant progress in understanding this arrhythmia accelerated with the era of operative treatment of this arrhythmia and intensified with the advent of catheter ablation. Through considerable trial and some error, effective "curative" therapies have evolved for paroxysmal AF and are evolving for persistent AF. It is becoming clear that no single mechanism suffices to explain AF in all its forms and multiple mechanisms are playing a role in the most complicated cases.     

Simultaneous occurrence of atrial fibrillation and atrial flutter

INTRODUCTION: Early reports suggested that some patients with "atrial fibrillation/flutter" might have atrial fibrillation in one atrium and atrial flutter in the other. However, more recent conceptions of atrial fibrillation/flutter postulate that the pattern is due to a relatively organized (type I) form of atrial fibrillation. We report the occurrence and ECG manifestations of simultaneous atrial fibrillation and flutter in patients undergoing attempted catheter ablation of atrial flutter. METHODS AND RESULTS: In patients undergoing radiofrequency ablation for atrial flutter, an attempt was made to entrain atrial flutter by pacing in the right atrium. The arrhythmias observed occurred following attempts at entrainment, or spontaneously in one case. Twelve transient episodes of simultaneous atrial fibrillation and flutter were observed in five patients. The atrial fibrillation was localized to all or a portion of one atrium, during which the other atrium maintained atrial flutter. In each case, the surface 12-lead ECG reflected the right atrial activation pattern. No patients had interatrial or intra-atrial conduction block during sinus rhythm, suggesting functional intra-atrial block as a mechanism for simultaneous atrial fibrillation/flutter. CONCLUSION: In certain patients, the occurrence of transient, simultaneous atrial fibrillation and flutter is possible. In contrast to prior studies in which it was suggested that left atrial or septal activation determines P wave morphology, the results of the present study show that P wave morphology is determined by right atrial activation. Functional interatrial block appears to be a likely mechanism for this phenomenon.     

Electroanatomic characteristics of atrial premature beats triggering atrial fibrillation in patients with persistent versus paroxysmal atrial fibrillation

APBs in Persistent Versus Paroxysmal AF. BACKGROUND: Although the electrical disconnection between the left atrium (LA) and pulmonary veins (PVs) by radiofrequency catheter ablation has been proven to be effective in controlling atrial fibrillation (AF), the recurrence rate is higher in patients with persistent AF (PeAF) than with paroxysmal AF (PAF). We hypothesized that the origin of the atrial premature beats (APBs) that trigger AF and the pattern of their breakthrough into the LA differ between PAF and PeAF. METHODS: We mapped 75 APBs (53 APBs triggering AF, 22 isolated APBs) from the LA and PVs in 26 patients with AF (age: 49.5 +/- 9.6, males: 23, PAF = 17, PeAF = 9), using a noncontact endocardial mapping (NCM) system. The location of the preferential conduction (PC) sites and their conduction velocity (CV) were compared. RESULTS: In patients with PeAF, the earliest activation (EA) site and exit of the PC were more frequently located on the LA side of the LA-PV junction as compared with PAF (P < 0.001). Eighty-one percent of the PCs were located in the area between the left and right superior PVs. The incidence of PCs was similar between the PeAF and PAF patients (P = NS). PCs were more commonly found with APBs inducing AF (63.3%) than with those not inducing AF (35.2%, P = 0.01). The CV of the PC was slower for PeAF than PAF (P < 0.001). The CV in the LA during sinus rhythm was also slower for PeAF than PAF (P < 0.01). CONCLUSION: PeAF was more frequently triggered by APBs from the LA side of the LA-PV junction than PAF and resulted in slower conduction than did PAF. These findings may help explain the higher potential for recurrence after electrical PV isolation in patients with PeAF.     

动脉粥样硬化与心房颤动

心房颤动（房颤）是临床上最常见的心律失常,不仅可以引起患者心功能不全且易发生血栓栓塞并发症,增加致残率和病死率。动脉粥样硬化是冠心病和缺血性脑卒中的主要病因。近年来研究表明,动脉粥样硬化对于房颤发生、发展和复发有一定预测作用,而房颤会促进动脉粥样硬化进展,增加血栓栓塞和动脉粥样硬化栓塞风险,但机制尚不完全清楚。目前,通过影像学、电生理学、血清学、组织病理学、免疫学等方法发现两者都可能与炎症反应、动脉内皮损伤或功能不全等因素有关,并可能相互影响。