Supraventricular ectopy and recurrence of atrial fibrillation after electrical cardioversion.

AIMS: Paroxysmal atrial fibrillation (AF) is usually preceded by a premature atrial complex (PAC). We hypothesized that patients with a high frequency of atrial ectopic activity after restoration of sinus rhythm following direct current cardioversion would be more likely to experience recurrence of AF. METHODS AND RESULTS: Forty-four patients with documented persistent AF were studied. A 24 h Holter recording was performed from the day of external direct current cardioversion. Patients were reviewed at 1 week, 1 month, and 6 months. After 6 months, 59% of patients had experienced a recurrence of AF. Neither the frequency of PACs nor the frequency or duration of supraventricular tachycardia (SVT) episodes predicted AF recurrence (P=0.60, 0.30, and 0.42, respectively). There was a trend towards maximum rate of SVT predicting recurrence of AF (P=0.08). CONCLUSION: Frequency of supraventricular ectopy or the number and length of SVT runs in the 24 h after restoration of sinus rhythm are not strong predictors of recurrence of AF after electrical cardioversion. A larger study would be required to detect a small predictive effect.     

Prior statin use and the incidence of in-hospital arrhythmia in acute coronary syndrome: A systematic review and meta-analysis

BackgroundThe benefit of prior statin use to reduce the incidence of arrhythmia in acute coronary syndrome (ACS) is still a matter of debate. Statins have multiple pleiotropic effects, which may reduce the incidence of in-hospital arrhythmia. A systematic review and meta-analysis were performed to evaluate prior statin use and the incidence of in-hospital arrhythmia in ACS.MethodsThis systematic review was conducted as per the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). We performed a literature search through Pubmed, Proquest, EBSCOhost, and Clinicaltrial.gov. A random-effect model was used due to moderate heterogeneity. Quality assessment was performed using Newcastle Ottawa Scale. Sensitivity analysis was performed by using leave one or two out method. PROSPERO registration number: CRD42022336402.ResultsNine eligible studies consisting of 86,795 patients were included. A total of 22,130 (25.5%) patients were in statin use before the index ACS event. The prevalence of old myocardial infarction, heart failure, hypertension, diabetes mellitus, and chronic renal failure and concomitant treatment with aspirin, clopidogrel, and beta blocker was higher in the prior statin group compared to no previous statin. Overall, prior statin use was associated with a significantly lower incidence of in-hospital arrhythmia during ACS compared to no previous statin (OR 0.60; 95% CI 0.49–0.72; P < 0.00001; I² = 54%, P-heterogeneity = 0.03). In subgroup analysis, previous statin use reduced the incidence of atrial fibrillation or atrial flutter (OR 0.64; 95% CI 0.43–0.95; P = 0.03; I² = 73%, P-heterogeneity = 0.01) and ventricular tachycardia or ventricular fibrillation (OR 0.57; 95% CI 0.49–0.65; P < 0.00001; I² = 8%, P-heterogeneity = 0.35).ConclusionsBased on aggregate patient data, prior statin use may reduce the incidence of in-hospital arrhythmia during ACS, particularly atrial fibrillation or atrial flutter and ventricular tachycardia or ventricular fibrillation.     

室上速并发心房颤动的电生理研究

目的探讨室上速并发心房颤动(房颤)的电生理特性及其发生机制。方法对38例室上速患者,根据有无房颤史分为两组,即房颤组18例,无房颤组20例。分别测量两组室上速周长、心房内压、心房各部位有效不应期、心房不应期离散度、心房最大不应期与室上速周长的比值,所有对象均行射频消融术治疗室上速,并行为期半年的随访,观察两组病人房颤的发生情况。结果房颤组与无房颤组的室上速周长分别为（326±9）ms,（331±11）ms,P>0.05。在窦性心律与室上速发作时,房颤组的心房不应期离散度均较无房颤组增加,房颤组的心房最大不应期与室上速周长的比值比无房颤组明显增加（P<0.05）。房颤组的心房最大不应期比无房颤组增加（P<0.05）,但却发生在心房的不同部位。结论(1)室上速合并房颤与室上速周长无明显关系。(2)心房不应期离散度是室上速合并房颤发生和维持的一个重要机制。(3)心房最大不应期与室上速周长的比值可能是室上速诱发房颤的另一个机制。     

Flecainide: Current status and perspectives in arrhythmia management

Flecainide acetate is a class IC antiarrhythmic agent and its clinical efficacy has been confirmed by the results of several clinical trials. Nowadays, flecainide is recommended as one of the first line therapies for pharmacological conversion as well as maintenance of sinus rhythm in patients with atrial fibrillation and/or supraventricular tachycardias. Based on the Cardiac Arrhythmia Suppression Trial study results, flecainide is not recommended in patients with structural heart disease due to high proarrhythmic risk. Recent data support the role of flecainide in preventing ventricular tachyarrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia associated both with ryanodine receptor and calsequestrin mutations. We herein review the current clinical data related to flecainide use in clinical practice and some concerns about its role in the management of patients with coronary artery disease.     

阵发性房颤患者心电图P波变化分析

目的分析阵发性心房颤动（PAF）患者心电图P波的变化。方法选择100例无器质性心脏病阵发性房颤患者（PAF组）,100例无房颤患者作为对照组（无PAF组）,采用体表心电图和超声心动图分别测量两组的V1导联P波时限（Pt）、V1导联P波终末负电势（Ptfv1）和左心房内径（LAD）、舒张末期左心室内径（LVD）、左心室射血分数（LVEF）等指标。结果 PAF组、无PAF组的Pt分别为（120±10）ms、（99±11）ms,Ptfv1分别为（0.051±0.023）mm·s、（0.026±0.010）mm·s,两组比较差异有统计学意义（P均〈0.01）;PAF组、无PAF组LAD分别为（33.6±3.9）mm、（32.7±4.2）mm,LVD分别为（44.6±4.1）mm、（42.7±4.3mm）,LVEF分别为（56.6±4.9）、（59.7±5.2）,两组比较差异无统计学意义（P均〉0.05）。结论阵发性房颤可引起心电图Pt及Ptfv1值增加,与左心房内径大小无相关。     

Study of surface electrocardiogram spectrum before and after pulmonary vein ablation in patients with persistent atrial fibrillation

Atrial fibrillation (AF) is the most common clinical cardiac arrhythmia and is usually treated with the electrical isolation of the pulmonary veins from the atria. However, it is estimated that about 30% of the patients undergoing this therapy will develop AF again. The purpose of this study was to test the dynamic changes of the spectra calculated in surface electrocardiograms (ECGs) before and after the ablation of the pulmonary veins. Surface ECGs of 14 patients with persistent AF undergoing this intervention were considered for this study. The QRS-T waves were subtracted from the ECGs using common spatial pattern, isolating the electrical activity of the atrium. The spectrum was then calculated and the main frequency peaks were identified. The smaller peaks with amplitude below 50% of the maximum were discarded. Eleven of the patients were followed up after the intervention for 1 to 6 months. Two of the patients developed AF again; the other 9 remained in sinus rhythm. For most of the patients, the spectrum showed more order after the intervention. However, the main frequency did not experience a significant decrease in average (5.1 Hz [±1.3] to 4.9 Hz [±1.0]). Interestingly, the increment or decrease of the main frequency did not correlate with the recurrence of AF or not.     

Usefulness of rate regulation through continuous ventricular pacing in patients with drug-controlled slower atrial fibrillation and normal or depressed left ventricular systolic function

We studied 33 clinically stable patients with permanent atrial fibrillation (AF), implanted with a ventricular demand rate-responsive (VVIR) pacemaker or an automatic defibrillator, in order to evaluate whether continuous right ventricular apex pacing (VP) conferring rate regulation may be advantageous when compared with slower drug-controlled AF. Devices were chronically programmed at ventricular backup pacing. Patients were divided in two groups according to their normal (n = 17) or depressed (n = 16) left ventricular systolic function (LVSF). Ventricular function was studied by using tissue Doppler and color M-mode and echocardiography, as well as B-type natriuretic peptide (BNP) measurements. Baseline data during AF were compared to corresponding measurements following a 1-month pacing period after the devices were programmed at a base rate of 70 beats/min. In both groups, VP worsened some indexes of left and right ventricular function (P < 0.05) without significantly affecting cardiac output, left ventricular filling pressures and BNP (P = not significant). We conclude that VP should not be considered advantageous compared to slower AF.     

Automatic atrial fibrillation and flutter detection by a handheld ECG recorder,and utility of sequential finger and precordial recordings

Background

Handheld ECG recorders may have algorithms which automatically inform the user of presence of arrhythmia. The main objectives of this study were to evaluate the accuracy of the arrhythmia diagnosis algorithm of Beurer ME90 recorder to diagnose atrial fibrillation (AF)/flutter, and to evaluate whether recording technique (finger versus precordial) affects diagnostic performance.

阵发性房颤射频消融术后空白期内房性心律失常与房颤远期复发的关系

目的 探讨阵发性房颤射频消融术后3个月（“空白期”）内房性心律失常的发作趋势与远期复发的关系.方法 入选在我院接受首次环肺静脉电隔离射频消融术的阵发性房颤患者50例,并于术后3个月内每月行24h动态心电图检查,同时进行术后定期临床随访和监测12个月.根据术后第12个月体表心电图、24h动态心电图监测及临床随访结果,分为房颤复发组和无复发组,比较复发组患者与无复发组患者术后3个月内房性心律失常发生率及随着时间推移两组房性心律失常的发作趋势.结果 术后第12个月体表心电图及24h动态心电图统计结果显示,房颤复发率为36.0％（18/50）,所有心电图中出现快速型房性心律失常心电图为26.9％,其中房颤20.2％、房扑2.0％、房速4.7％;房性早搏20.1％;窦性心动过缓2.0％.复发组患者术后3个月内房性心律失常的发生率高于无复发组（41.1％比10.2％,P＜0.05）,复发组患者术后3个月内房性心律失常的发生率维持在较高水平（术后3个月分别为44.4％、41.8％、38.5％,P＞0.05）.无复发组患者术后3个月可出现房颤复发,随着时间推移房性心律失常的发生率呈降低趋势（术后3个月分别为18.7％、10.5％、4.4％,P＜0.01）.结论 早期复发不能代表消融失败和晚期复发,但早期房性心律失常发作频繁,则晚期房颤复发的危险性增加.     

40例成年人正常心房界嵴的形态学特征研究

目的　通过界嵴的解剖学和组织学研究 ,以评估其在心房电生理中的作用。方法　观察 4 0只成人心脏标本界嵴的形态并测量界嵴的高度和宽度。对界嵴纵行和横行切片 ,分析其组织学特征。结果　界嵴的各部分不是均匀一致的 ,其上、中、下 3部分的高度 (mm)分别为 (6 .0 1± 1.31) ,(4.13± 1.76 )和 (2 .0 7± 0 .79) ;平均宽度为 (6 .2 6± 1.87)。 5 6 %的标本界嵴下部呈平坦状 ,几乎无心内膜隆起。从界嵴的中部向下 ,近心外膜侧 ,开始出现横行纤维。横行纤维向左与腔静脉窦的纤维相延续。结论　界嵴的解剖学和组织学特征可能为其在心房电生理中的一些现象提供部分证据