预激综合征合并心房颤动的诊治进展

预激综合征（WPW）合并心房颤动（房颤）可引起快速心室反应,发展为心室颤动,使血流动力学恶化,危及生命,因此及时诊断和合理治疗WPW合并房颤具有重要临床意义。现对WPW并发房颤可能与旁路电生理特性、旁路对心房电生理的影响、旁路逆传致波峰碰撞等因素有关的机制;在心电图上的诊断特点;电复律治疗的适应证和注意事项;普罗帕酮、胺碘酮、伊布利特等的药物治疗;射频消融治疗及术后的复发随访进行综述。     

Why is Warfarin Underutilized in Patients with Atrial Fibrillation?

BACKGROUND: Identification of patients at risk for PAF recurrence after AP ablation is important because of the necessity for additional therapies. OBJECTIVES: To determine whether Maximum P-wave duration (Pmax) and P-wave dispersion (Pd ) detected on surface ECG after successful accessory pathway (AP) ablation can predict the recurrence of paroxysmal atrial fibrillation (PAF). METHODS: Seventy-eight patients with Wolff-Parkinson-White (WPW) syndrome who had at least one documented PAF episode and underwent catheter ablation were enrolled. Pmax, minimum P-wave duration (Pmin) and Pd were determined on a surface ECG recorded on a high resolution computer screen on day 2 after ablation of the AP. RESULTS: There was no significant difference in terms of basic clinical data and electrophysiological findings between patients with (Group-1, n = 19) and without (Group-2, n = 59) recurrence of PAF during follow-up of 21 +/- 10 months. Pmax and Pd were significantly higher in Group-1 than Group-2 (120 +/- 15 vs. 96 +/- 10 ms and 47 +/- 12 vs. 25 +/- 7 ms, respectively; p < 0.001 for both). Pmin didn't differ significantly. A Pmax value of > or = 103 ms separated Group-1 from Group-2 with a sensitivity of 84.2%, specificity of 72.9%, positive predictive value of 50%, and negative predictive value of 93.5%. A Pd value of > or = 32.5 ms separated Group-1 from Group-2 with a sensitivity of 89.5%, specificity of 84.7%, positive predictive value of 65.4%, and negative predictive value of 96.2%. Pmax (p < 0.010) and Pd (p < 0.001) were found to be significant univariate predictors of PAF, whereas only Pd remained significant in multivariate analysis (p = 0.037). CONCLUSION: Pd > or = 32.5 ms and Pmax > or = 103.0 ms predict the recurrence of PAF after ablation with acceptable positive and negative predictive values. Pd > or = 32.5 ms is an independent predictor of recurrence of PAF after catheter ablation in patients with WPW syndrome.     

Clinical and Electrocardiographic Variables Can Predict Atrial Fibrillation in Patients with Atrioventricular Accessory Pathways

Background: Risk stratification of sudden death in patients with Wolff-Parkinson-White syndrome is based on the refractory period of the atrioventricular accessory pathway and the probability of spontaneous atrial fibrillation. Risk stratification based on invasive studies does not seem cost-effective in the radiofrequency ablation era, and, although sensitive, noninvasive tests are not used because of their low specificity. We sought to determine whether clinical and electrocardiographic variables can predict spontaneous atrial fibrillation in patients with an accessory pathway. Methods: We studied 420 consecutive patients treated by radiofrequency catheter ablation who had a single atrioventricular accessory pathway and the Influence of four variables: age, gender, location of the accessory pathway as determined by the site of successful radiofrequency ablation, and the presence of a manifest accessory pathway in the ECG was analyzed by multiple logistic regression analysis and a chi-square test. The development model, comprised of data from the first 359 patients, included 58 patients with spontaneous atrial fibrillation and 301 patients without spontaneous atrial fibrillation during follow-up. The likelihood ratio derived from the development model was validated in the last 61 patients. Results: Patients with spontaneous atrial fibrillation occurring before accessory pathway ablation were more often male and were older than those without atrial fibrillation. Atrial fibrillation occurred more frequently in manifest than in concealed accessory pathways, and the presence of posteroseptal accessory pathway strongly correlated with spontaneous atrial fibrillation. Conclusion: The probability of spontaneous atrial fibrillation was higher in men with a manifest posteroseptal accessory pathway and increased with age. A.N.E. 2000;5(1):45–52     

Regular Wide QRS Complex Tachycardia During Atrial Fibrillation in a Patient with Preexcitation Syndrome: A Case Report

AV Conduction in WPW. We report an unusual case of a relatively regular wide QRS complex tachycardia alternating with periods of an irregular narrow QRS complex tachycardia during atrial fibrillation in a patient with Wolff-Parkinson-White syndrome. Both tachycardias resulted from atrial fibrillation, the wide QRS complex tachycardia being due to 2:1 AV conduction of a type I atrial fibrillation across a posteroseptal accessory AV connection.     

Maintenance of Sinus Rhythm after Cardioversion of Atrial Fibrillation in Patients with Lone Atrial Fibrillation and Patients with Hypertension

Background: The success rate and prognosis of cardioversion of atrial fibrillation (AF) in patients with organic heart disease is well known. In contrast, little data exist about cardioversion success and maintenance of sinus rhythm (SR) in patients with lone AF and in patients with hypertension as the only underlying cardiovascular disease. Methods: In a prospective cardioversion registry 148 of 181 patients (81.8%) with lone AF (age 58 ± 13 years, duration of AF 7.6 ± 19 weeks) and 120 of 148 patients (81.1%) with hypertension (age 62 ± 10 years, duration of AF 6.6 ± 21 weeks) had successful cardioversion and were followed for 7.7 ± 1.9 months. Results: At follow-up, 120 patients (81.1%) with lone AF were in SR, and 18 of these patients had had repeated cardioversion during follow-up (AF total recurrence rate 31.1%). In stepwise regression analysis, the number of previous cardioversions was predictive of rhythm at follow-up (P = 0.0453). Rhythm at follow-up did not differ between patients who were or were not on antiarrhythmic drugs. At follow-up 96 patients (80%) with hypertension were in SR, and 9 of these had had repeated cardioversion during follow-up (AF total recurrence rate 27.5%). As in lone AF, the recurrence rate of AF did not differ between patients with or without antiarrhythmic drug treatment, and in multivariate regression analysis, the number of previous cardioversions was the only clinical predictor of rhythm at follow-up (P = 0.0284). Conclusions: Even in patients with such benign conditions as lone AF or hypertension as the only underlying disease, the prognosis of cardioversion in terms of maintenance of SR is poor. Future studies of rhythm control versus rate control need to include not only patients with organic heart disease but also patients with lone AF and patients with hypertension, since the long-term benefits of these two strategies remain unclear even in these subsets of patients.     

Atrial electrophysiologic properties of patients with asymptomatic Wolff-Parkinson-White syndrome

To evaluate the existence of a peculiar atrial electrophysiologicsubstrate, we studied 18 patients with asymptomatic Wolff-Parkinson-White(WPW) syndrome. These patients were compared with 10 agematchednormal subjects (N). Effective and functional refractory periodswere determined at two right atrial sites (high and low in thelateral wall), during atrial pacing (100 min^–1) and attwice diastolic threshold. Disperson (D) of effective (ERP)and functional (FRP) refractoriness was evaluated as the differencebetween refractory periods at the two atrial sites. WPW patientsshowed significantly lower mean values of effective and functionalrefractoriness at both atrial sites and significantly highermean values of D-ERP and D-FRP. Moreover, in calculating thehighest normal values of D-ERP and D-FRP (as mean values ofN plus 2SD) it was observed that WPW with abnormal values ofD showed a statistically (x² test) higher incidence (100%) ofinduced atrial fibrillation (AF). These findings indicate theexistence of both an abnormal atrial electrophysiologic substrateand of a higher vulnerability in WPW. Finally, AF was inducedgenerally at the site with the lower refractoriness (i.e. lowlateral site). This should be taken into account when consideringhow atrial fibrillation can be induced more easily.     

低位房间隔起搏对病窦综合症伴发作性房颤患者的临床应用

目的:探索低位房间隔起搏导线定位方法,评价房间隔起搏对病窦综合征患者房颤的预防作用。方法:病窦综合征患者48例,以X线及心电图特征定位,主动固定心房电极于低位房间隔,观察起搏后P波时限的变化及房颤的发作频率。结果:所有患者经房间隔起搏后,P波时限均显著缩短,118.00±24.00ms比93.00±16.00ms,差异有统计学意义;原有心房内传导延缓者,起搏后阵发性房颤发作频率明显减少,而心房内传导正常者,房颤发作无明显减少。结论:采用主动固定电极导线在低位房间隔起搏是安全、可行的,它能明显缩短左、右心房激动时间,使心房的除极趋于同步化;对伴房间传导阻滞者,房间隔起搏能减少房颤发作。     

Atrial Septal Aneurysm and Dilated Sinus of Valsalva in a Patient with Wolff-Parkinson-White Syndrome

Atrial septal aneurysm and a dilated sinus of Valsalva were noted on echocardiography in a 30-year-old male with Wolff-Parkinson-White syndrome. The relative low probability of all three coexisting by chance alone suggests the possibility of a common developmental origin.     

双腔频率应答起搏对病窦综合征合并的阵发性心房颤动的干预

探讨双腔频率应答起搏对病窦综合征(SSS)合并的阵发性心房颤动(简称房颤)的窦性心律维持及电生理干预。48例SSS并阵发性房颤患者安装了双腔频率应答起搏器,通过起搏器正确的心房感知监测房颤的发作情况,在窦性心律时测量P波时限和P波离散度,心脏B超测量左房内径、左室射血分数。比较术后1,12个月以及房颤控制组与复发组上述指标的差异。结果:置入起搏器术后1年,房颤控制和房颤负荷减少37例,占77%。术后1个月与1年左房内径,P波时限,房颤平均每天发作时间、发作次数均有显著性差异(3.6±0.6cmvs3.2±0.5cm,129.2±11.0msvs111.2±9.3ms,93.6±10.4min/dvs42.8±9.6min/d,8.1±3.2次/天vs5.3±1.4次/天,P<0.001)。与术后房颤复发组比较,房颤控制组术前左房内径较小,P波时限较短、离散度小(P<0.001)。结论:双腔频率应答起搏对SSS合并的阵发性房颤有预防和治疗作用。     

心房颤动伴预激综合征1例

患者,男,41岁,因持续心悸伴心动过速就诊。心电图示P波消失,心室率193次/min;QRS波的形态基本一致,但时限宽窄不一,可见最短的RR间距200ms。结合后期记录的窦性心电图及其QRS波起始部形态一致的特点,不难做出预激综合征合并心房颤动的诊断。     

Improvement of Echocardiographic M-Mode Detection of Ventricular Precontraction in the Wolff-Parkinson-White Syndrome by Transesophageal Atrial Pacing

Background: The purpose of this study was to evaluate the accuracy of conventional M-mode echo-cardiography in localizing the site of the accessory pathway in 21 patients with overt Wolff-Parkinson-White (W-P-W) syndrome during sinus rhythm (SR) and during transesophageal atrial stimulation (TAS). Methods: The invasive electrophysiological study was used as a reference, and the results were compared with the pathway localization obtained through algorithmic interpretation of the 12-lead electrocardiogram during SR. Echocardiographic left parasternal short-axis recordings were performed during SR and TAS (100–120 beats/min). The shortest electromechanical interval measured at six different sites of the atrioventricular valve plane from the onset of the delta wave to the peak of the precontraction defined the pathway localization. Results: Correct localization of the accessory pathway with echocardiography could be attained in 14 patients during SR (14 of 21, or 66%). With the aid of TAS, correct pathway localization was achieved for an additional 2 patients, making a total of 16 patients (76%). During TAS, precontraction was enhanced in 63% of the patients. With the algorithmic electrocardiographic interpretation, the localization of the accessory pathway was correct in 13 of the 21 patients (62%). The differences were not significant. Conclusion: M-mode echocardiography is a simple and readily available method for the identification of precontraction. The method is comparable to pathway localization through algorithmic ECG interpretation during SR. Transesophageal left atrial pacing during echocardiography can amplify the precontraction and thereby facilitate the interpretation of the wall motions.     

Amiodarone for the Restoration of Sinus Rhythm in Patients with Atrial Fibrillation

Although the use of amiodarone for the treatment of atrial fibrillation has increased, reports of its use for the restoration of sinus rhythm have been conflicting. In a recent prospective, randomized, single-blind, placebo controlled study, we examined the efficacy and safety of amiodarone as initial treatment to restore sinus rhythm in patients with atrial fibrillation of varying duration. We studied 335 patients (169 men, 166 women), aged 27-78 years (mean age 65 +/- 10 years), with symptomatic atrial fibrillation, who presented to the emergency room or to our clinic. Patients randomized to amiodarone ( n = 173) received 300 mg intravenously over 1 hour followed by 20 mg/kg over 24 hours. Oral administration was initiated simultaneously at 600 mg/day in 3 divided doses for one week followed by 400 mg/day, in two doses, for three weeks. Amiodarone was almost twice as likely as placebo to restore sinus rhythm (85% vs. 43%, p < 0.0001). Larger left atrial size and longer duration of atrial fibrillation decreased amiodarone's effectiveness. These factors were also associated with longer duration of treatment before conversion to sinus rhythm. We observed relatively few and only minor complications despite relatively high doses of amiodarone administered to achieve high serum concentrations. In conclusion, our findings indicate that amiodarone is an effective and safe antiarrhythmic drug even when administered in large doses. It may be used for the restoration of sinus rhythm when rapid cardioversion is not needed.     

Left Atrial Conduction Along the Coronary Sinus During Ectopic Atrial Tachycardia and Atrial Fibrillation:

Introduction: Correlation function analysis was applied to endocardial electrograms to investigate conduction patterns along the coronary sinus (CS) during sinus rhythm (SR) and atrial tachycardias.
Methods and Results: Eighteen recordings were obtained from 14 patients with supraventricular tachycardias. Five atrial fibrillation (AF) recordings were compared to 10 SR recordings and 3 ectopic atrial tachycardia (EAT) recordings. The maximum correlation coefficient was used to assess similarity between signals, i.e., if they originate from the same wavefront. The cumulative time delay, calculated as pairwise summation of interelectrode time delays, was used as an indicator of activation sequence along the CS. Method validation using SR showed right-to-left conduction with high correlations in 8 of 10 recordings indicating one single wavefront. EAT recordings showed consistent left-to-right conduction with left atrial foci and right-to-left with right atrial focus and lower correlations than SR. All 5 AF recordings showed predominantly left-to-right conduction direction, also with correlations lower than SR.
Conclusion: (1) Correlation function analysis can be used to assess agreement between signals and direction of activation spread. (2) Due to the position of CS, the results can be used to derive mechanisms of interatrial conduction. (3) Consistency in electrical activity propagation along CS is common in AF. (J Cardiovasc Electrophysiol, Vol. 14, pp. S148-S153, October 2003, Suppl.)     

Inducibility of Atrial Fibrillation Before and After Radiofrequency Catheter Ablation of Accessory Atrioventricular Connections

Inducibility of Atrial Fibrillation. Introduction: The purpose of this study was to evaluate the inducihility of atrial fibrillation in patients with an accessory atriovcentricular connection (AAVC) and to determine if the inducibility of atrial fibrillation is altered after successfulradiofrequency catheter ablation of the AAVC.
Methods and Results: Thirty-seven patients with an AAVC and 36 control patients wereprospectively evaluated using a standardized atrial pacing protocol. The high right atrium waspaced using a 25-beat drive train, 1.5-second intertrain pause, 10-mA pulse amplitude, and 2-msec pulse duration at cycle lengths of 250 to 100 msec, in 10-msec decrements. Pacing wasperformed twice at each cycle length. Thirty patients with an AAVC underwent repeat atrialoverdrive pacing after successful radiofrequency ablation of the AAVC. Atrial fibrillation wasinduced in 26 (70%) patients with an AAVC and 22 (61 %) controls (P = NS). Atrial flutter wasinduced in 26 (70%) patients with an AAVC and 22 (61%) controls (P = NS). The cumulativepercentage of patients with atrial fibrillation/flutter induced at each pacing cycle length was thesame in each group. There was no difference in the duration of atrial fibrillation/flutterbetween control patients and patients with an AAVC. Among the 30 patients who underwentrepeat atrial overdrive pacing after radiofrequency ablation of an AAVC, there was no difference in the inducibility or duration of atrial fibrillation/atrial flutter after ablation compared tobaseline.
Conclusion: These findings indicate that the vulnerability of the atrium to fibrillate inresponse to atrial pacing is independent of the presence of an AAVC.     

Conversion of Atrial Fibrillation to Sinus Rhythm Using Acute Intravenous Procainamide Infusion

The efficacy and safety of intravenous procainamide in the conversion of atrial fibrillation was investigated. A total of 114 patients without severe heart failure were randomized to receive either intravenous procainamide (1 g over 30 minutes, followed by an infusion of 2 mg/min over 1 hour) or placebo in a double-blind trial. Digoxin (0.5 mg intravenously) was administered to all patients who had not previously been receiving digoxin. Treatment was considered successful if sinus rhythm was restored within 1 hour after starting the infusion. Conversion to sinus rhythm was achieved in 29 (50.9%) of the 57 patients treated with procainamide and in 16 (28.1%) of the 57 who received placebo (P 0.012). When the duration of the atrial fibrillation was 48 hours, conversion to sinus rhythm was achieved in 29 (69%) of the 42 patients receiving procainamide and in 16 (38.1%) of those receiving placebo (P 0.004). None of the patients with atrial fibrillation lasting 48 hours converted to sinus rhythm in either group. Another factor that played a role in the restoration of sinus rhythm was the size of the left atrium: the smaller the left atrium, the larger the success rate. The results of the study suggest that intravenous procainamide is an effective and safe means for the rapid termination of atrial fibrillation of recent onset and that its success rate is inversely related to the size of the left atrium. However, the drug is ineffective in the conversion of atrial fibrillation lasting more than 48 hours.     

急性冠状动脉综合征合并房颤高龄患者抗栓治疗策略新进展

高龄老年急性冠脉综合征患者合并房颤比率高,面临缺血及出血双重高风险.针对该类人群的抗栓治疗方案,尚缺乏统一的共识.本文就目前急性冠脉综合征合并房颤高龄患者的抗栓治疗进行展综述.     

心房颤动合并冠状动脉支架置入术患者的联合抗栓优化策略

心房颤动患者合并冠状动脉支架置入术后应接受口服抗凝药和双联抗血小板药的三联抗栓治疗。然而,华法林联合阿司匹林和氯吡格雷的三联抗栓治疗出血风险高,哪种联合方式更加安全有效便成为抗栓治疗优化策略的关注焦点。现就心房颤动合并冠状动脉支架置入术患者的各种联合抗栓治疗方案的有效性及安全性综述如下。     

Atrial Fibrillation-triggered Ventricular Fibrillation in a Patient with Early Repolarization Syndrome

A 54-year-old man with early repolarization syndrome (ERS) implanted with an implantable cardioverter-defibrillator (ICD) developed persistent atrial fibrillation (AF) three years after the implantation. Similarly, the remote monitoring system begun frequently detecting ventricular fibrillation (VF) and polymorphic ventricular tachycardia (PVT). Longer RR intervals were repeatedly observed just before the initiation of PVT/VF. Catheter ablation for AF successfully diminished both the PVT and VF events.     

心房颤动导管消融术后快速性房性心律失常的机制和治疗

随着心房颤动导管消融治疗的日益广泛开展,导管消融术后快速性房性心律失常（即继发性房性心律失常,包括房性心动过速和心房扑动）逐渐成为临床心律失常治疗的关注热点,其机制在不同患者中不尽相同,甚至同一患者亦可涉及多种机制,因此这种心律失常的处理可能较心房颤动本身更为棘手。现就心房颤动导管消融术后发生快速性房性心律失常的可能机制及其防治策略作一综述。