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1.
Catheter ablation of atrial fibrillation (AF) has evolved as a potential curative option for drug-refractory AF in recent years. AF not only causes physical morbidity but also jeopardizes the mental and social health of the patient as well as predisposing the patient to increased risk of thromboembolic events. Therefore, the primary end points of AF ablation have been restoration of sinus rhythm, improvement in the quality of life and lowering the risk of cerebrovascular accidents. However, even in the best hands, AF ablation is yet to be a total success. Several risk factors of AF and parameters of catheter ablation influence the short- and long-term ablation outcome. This article reviews all the information that has been contributed by prominent independent researchers over the last decade.  相似文献   

2.
Paroxysmal AF has been known to be initiated by ectopic beats, especially in the pulmonary veins (PVs), and radiofrequency catheter ablation could cure it. We considered that the spontaneous transition from typical atrial flutter to AF also could be initiated by ectopic beats. Twenty patients (18 men, mean age 66 +/- 14 years) with episodes of spontaneous transition from typical atrial flutter to AF were included in this study. They underwent detailed mapping of both atria. All the patients had spontaneous AF initiated by ectopic beats, and all of them had typical atrial flutter and spontaneous transition from typical atrial flutter (12 patients with counterclockwise atrial flutter and 8 patients with clockwise atrial flutter) to AF. The transition was initiated by ectopic beats from the PVs (17 foci, 85%), crista terminalis (2 foci, 10%), and superior vena cava (1 focus, 5%). After successful ablation of AF foci, typical atrial flutter was induced again, but no spontaneous transition was found after at least 10 minutes of observation. We concluded that paroxysmal AF and spontaneous transition from typical atrial flutter to AF were initiated by ectopic beats, and successful catheter ablation of the ectopic foci can eliminate paroxysmal AF and spontaneous transition from typical atrial flutter to AF.  相似文献   

3.
Deglutition induced supraventricular tachycardia is an uncommon condition postulated to be a vagally mediated phenomenon due to mechanical stimulation. Patients usually present with mild symptoms or may have severe debilitating symptoms. Treatment with Class I agents, beta blockers, calcium channel blockers, amiodarone and radiofrquency catheter ablation has shown to be successful in the majority of reported cases. We report the case of a 46-year-old healthy woman presenting with palpitations on swallowing that was documented to be transient atrial tachycardia with aberrant ventricular conduction as well as transient atrial fibrillation. She was successfully treated with propafenone with no induction of swallowing-induced tachycardia after treatment. This is also the first case to show swallowing-induced atrial tachycardia and atrial fibrillation in the same patient.  相似文献   

4.
There is growing evidence to suggest a role for the renin-angiotensin system (RAS) in the pathogenesis of atrial fibrillation (AF). Experimental animal data suggest RAS-dependent mechanisms for the development of a structural and electrophysiologic substrate for AF. This is consistent with clinical data demonstrating the effectiveness of RAS blockade in preventing new-onset or recurrent AF in a variety of patient populations including patients with hypertension and left ventricular hypertrophy, congestive heart failure, and those undergoing electrical cardioversion for AF. This review summarizes experimental and clinical evidence to date relating to the role of RAS in the pathogenesis of AF, and the efficacy of its inhibition in managing this common arrhythmia.  相似文献   

5.
Impact of premature atrial contractions in atrial fibrillation   总被引:2,自引:0,他引:2  
In spite of the increasing knowledge about paroxysmal atrial fibrillation (PAF), details on mode of initiation in unselected patients are scarce. This paper focuses on trigger mechanisms of spontaneous onset of AF in consecutive patients with PAF. One hundred eight consecutive patients with two or more ECG documented AF episodes within the previous year had a 24-hours Holter recording performed. All AF episodes (n = 157) were reviewed and, within the last 10 beats prior to AF initiation. PP intervals were measured on 25 mm/s paper printouts and premature atrial contractions (PACs) were counted. Additionally, randomly selected coupling intervals (PP') for PACs not triggering AF were measured and compared to AF triggering intervals and to PP' intervals from healthy controls. PACs preceded all AF episodes. AF initiation displayed a wide variety in terms of PP coupling intervals and number of PACs prior to initiation within and between subjects. In episodes with PACs within the last 10 beats prior to initiation, we observed a long-short PP sequence at the time of initiation. Mean PP' interval (+/- SE) for AF triggering PACs was 403 +/- 9 ms, significantly shorter, P < 0.0001, than PP' for nontriggering PACs (584 +/- 8 ms) and PACs in healthy controls (589 +/- 6 ms). However, a large proportion of nontriggering PACs had short PP' coupling intervals without triggering AF. These observations highlight the importance of other factors than the trigger per se, such as the arrhythmogenic substrate, and suggest that therapeutic maneuvers aimed at curing PAF should target these as well as the trigger mechanisms.  相似文献   

6.
AF threshold and the other electrophysiological parameters were measured to quantify atrial vulnerability in patients with paroxysmal atrial fibrillation (PAF, n = 47), and those without AF (non-PAF, n = 25). Stimulations were delivered at the right atrial appendage with a basic cycle length of 500 ms. The PAF group had a significantly larger percentage of maximum atrial fragmentation (%MAF, non-PAF: mean +/- SD = 149 +/- 19%, PAF: 166 +/- 26%, P = 0.009), fragmented atrial activity zone (FAZ, non-PAF: median 0 ms, interquartile range 0-20 ms, PAF: 20 ms, 10-40 ms, P = 0.008). Atrial fibrillation threshold (AF threshold, non-PAF: median 11 mA, interquartile range 6-21 mA, PAF: 5 mA, 3-6 mA, P < 0.001) was smaller in the PAF group than in the non-PAF group. Sensitivity, specificity, and positive predictive value of electrophysiological parameters were as follows, respectively: %MAF (cut off at 150%, 78%, 52%, 76%), FAZ (cut off at 20 ms, 47%, 84%, 85%), AF threshold (cut off at 10 mA, 94%, 60%, 81%). There were no statistically significant differences between the non-PAF and PAF groups in the other parameters (effective refractory period, interatrial conduction time, maximum conduction delay, conduction delay zone, repetitive atrial firing zone, wavelength index), that were not specific for PAF. In conclusion, the AF threshold could be a useful indicator to evaluate atrial vulnerability in patients with AF.  相似文献   

7.
Failure of current pharmacological therapy for atrial fibrillation in maintaining sinus rhythm may be due to structural atrial remodeling caused by inflammation and fibrosis. Upstream therapy that interferes in the structural remodeling process may be effective in maintaining sinus rhythm. This article reviews upstream therapy in atrial fibrillation. Various prospective and retrospective studies demonstrate that upstream therapy, consisting of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, statins, fish oils, glucocorticoids, or moderate physical activity, is associated with a reduced incidence of new-onset atrial fibrillation (i.e., primary prevention) and with a reduced recurrence of atrial fibrillation (i.e., secondary prevention). Larger clinical trials are required to further elucidate the position of upstream therapy in the primary and secondary prevention of atrial fibrillation.  相似文献   

8.
In a substantial number of patients, AF recurs after successful electrical cardioversion. The purpose of this study was to investigate if the atrial arrhythmias recorded immediately after cardioversion are associated with the risk of recurrence of the arrhythmia and to compare the prognostic significance of this parameter with that of other established risk factors. In a series of 71 patients, the risk factors for recurrence of AF during the first year after successful electrical cardioversion were analyzed. A new parameter that was investigated was the frequency of atrial premature beats and the presence of runs of supraventricular tachycardia in the Holter recording started immediately after the cardioversion. Age, left atrial size, left ventricular systolic function, duration of the arrhythmia before cardioversion, underlying cardiac disease, or medication taken were not found to be predictive of recurrence of the arrhythmia. However, the natural logarithm of the number of atrial premature complexes per hour of the Holter recording in the 37 patients in whom AF recurred was higher compared to that of the 34 patients who maintained sinus rhythm (P < 0.0005). The same was true if only the first 6 hours of the recording were analyzed (P < 0.0005). There was a trend for more frequent arrhythmia recurrence if runs of supraventricular tachycardia were present. The finding of > 10 atrial premature complexes per hour in the recording had a relative risk of 2.57 (1.51-4.37), a positive predictive accuracy of 76.5%, and a negative predictive accuracy of 70.3% for subsequent arrhythmia recurrence. We can conclude that frequent (> 10/hour) atrial premature complexes in the Holter recording after electrical cardioversion for AF is a significant risk factor for recurrence of the arrhythmia.  相似文献   

9.
BACKGROUND: Paroxysmal atrial fibrillation (PAF) transits to permanent atrial fibrillation (PEAF). The current study was to determine whether a P wave-triggered P wave signal averaged electrocardiogram (P-SAECG) and chemoreflexsensitivity (CHRS) are useful to predict a conversion to PEAF in patients with PAF. METHODS: The filtered P wave duration (FPD) and the root mean square voltage of the last 20 ms of the P wave (RMS 20) were measured by P-SAECG. The ratio between the difference of RR intervals in the ECG and venous pO2 before and after 5-minutes oxygen inhalation is measured (ms/mmHg) for the determination of CHRS. Results: A total of 180 patients with PAF were enrolled and followed for a mean of 22.5 months. PEAF occurred in 38 patients (21%) and these patients had a significantly larger left atrial size (43.2 +/- 4.9 vs. 41.0 +/- 5.4 mm, P = 0.021), a significantly longer FPD (158.8 +/- 18.2 vs. 136.7 +/- 16.6 ms, P < 0.0001), and a significantly lower CHRS (1.96 +/- 0.99 vs. 2.44 +/- 1.19 ms/mmHg, P = 0.024) than patients with PAF. Patients with PEAF tended to have a lower RMS 20 (2.38 +/- 0.65 vs. 2.75 +/- 1.18 microV, P = 0.067) than patients with PAF. The chi(2) test showed that the combination of FPD > or = 145 ms, RMS 20 < or = 3.0 microV, left atrial size > or = 41 mm, and CHRS < or = 2.0 ms/mmHg had the best predictive power for PEAF. Patients who fulfilled these criteria had a 12-fold increased risk for a conversion from PAF to PEAF. CONCLUSIONS: Our results show that a P-SAECG, an analysis of CHRS, and left atrial enlargement are clinical predictors of a progression from PAF to PEAF.  相似文献   

10.
The prevalence of AF is known to increase in the elderly. Some electrophysiological changes were reported in these patients, but the effects of age on AF inducibility and other electrophysiological signs associated with atrial vulnerability are unknown. The purpose of the study was to evaluate the effects of age on atrial vulnerability and AF induction. The study consisted of 734 patients (age 16-85 years, mean 61 +/- 15 years) without spontaneous AF who were admitted for electrophysiological study. Study was indicated for dizziness or ventricular tachyarrhythmia. Programmed atrial stimulation was systematically performed. One and two extrastimuli were delivered in sinus rhythm and atrial driven rhythms (600, 400 ms). Univariate and multivariate analysis of several clinical and electrophysiological data were performed. AF inducibility, defined as the induction of an AF lasting > 1 minute, was paradoxically and significantly decreased in elderly (> 70 years) patients compared to younger patients (< 70 years) (P < 0.01). AF inducibility was present in 40% of 62 patients < 40 years, 39% of 99 patients age 40-50 years, 37% of 130 patients age 50-60 years, 38% of 222 patients age 60-70 years, and only 28% of 221 patients > 70 years. There was no significant correlation with the sex, the presence of dizziness, the presence or not of an underlying heart disease, the left ventricular ejection fraction, and the presence of salvos of atrial premature beats on 24-hour Holter monitoring. There was a significant correlation with a longer atrial effective refractory period in the elderly (226 +/- 41 ms) than in younger patients (208 +/- 31 ms) (P < 0.001). Other electrophysiological parameters of atrial vulnerability did not change significantly. Increased atrial refractory period and age >70 years were independent factors of decreased AF inducibility. Programmed atrial stimulation should be interpreted cautiously before the age of 70 years. AF induction is facilitated by the presence of a short atrial refractory period in these patients. Surprisingly, AF inducibility decreases in patients > 70 years because their atrial refractory period increases. Therefore, increased AF prevalence in these patients should be explained by nonelectrophysiological causes.  相似文献   

11.
Atrial fibrillation (AF) is the most common arrhythmia seen in clinical practice, and is associated with increased morbidity and mortality. Management of AF is challenging due to the modest efficacy of antiarrhythmic drug therapies, some of which have significant adverse effects or toxicity. Nonpharmacological treatment of AF, including AF ablation, has recently evolved as an attractive, efficacious and potentially ‘curative’ therapeutic modality in selected patients. This article reviews various interventional therapeutic options for the management of AF, appropriate patient selection and clinical implications.  相似文献   

12.
Atrial pacing with dedicated algorithms for prevention and termination of atrial tachyarrhythmias is under clinical evaluation. A patient is described with persistent symptomatic AF. After cardioversion and implantation of a DDDRP pacemaker before planned AVN ablation, the patient was free of symptoms. Early after implant, one cardioversion of AF was necessary. Over the course of 12 months, only five episodes of atrial tachyarrhythmia occurred, all automatically pace terminated within 24 hours. Thus, selected patients with persistent AF may benefit from preventive atrial pacing since the tachyarrhythmia can organize intermittently to a degree sufficient for pace termination.  相似文献   

13.
Background: Atrial tachycardia (AT) is commonly encountered after atrial fibrillation (AF) ablation. But no study exclusively on noncavotricuspid isthmus‐dependent right AT (NCTI‐RAT) post‐AF ablation has been reported. The present study aims to describe its prevalence, electrophysiological mechanisms, and ablation strategy and to further discuss its relationship with AF. Methods: From July 2006 to November 2009, 350 consecutive patients underwent catheter ablation for paroxysmal AF. A total of seven patients (2.0%) developed NCTI‐RAT after left atrium ablation for AF. In these highly selected patients (two male, mean age 54 ± 11 years, mean left atrium diameter of 34 ± 7 cm), all had circumferential pulmonary vein isolation in their initial procedures and three of them had additional complex fractionated electrograms ablation in the left atrium and the coronary sinus. Results: Totally, nine NCTI‐RATs were mapped and successfully ablated in the right atrium with a mean cycle length of 273 ± 64 ms in seven patients. Five ATs in three patients were electrophysiologically proved to be macroreentry and the remaining four were focal activation. All the ATs were successfully abolished by catheter ablation. After a mean follow‐up of 29 ± 15 months post‐AT ablation, all patients were free of AT and AF off antiarrhythmic drugs. Conclusions: NCTI‐RAT is relatively less common post‐AF ablation. Totally, 2.0% of paroxysmal AF patients were revealed to have NCTI‐RAT. (PACE 2011; 34:391–397)  相似文献   

14.
Background: Long‐term rapid atrial pacing may result in nerve sprouting and sympathetic hyperinnervation in atrial fibrillation (AF) in dogs. Whether peptidic nerve is involved in neural remodeling is unclear. Method and Results: We performed rapid left atrial pacing in six dogs to induce sustained AF. Tissues from six healthy dogs were used as controls. Nerve was identified by immunocytochemical techniques. The degree of nerve innervation was quantified by measuring the amount of staining area for each antibody and the heterogeneity of nerve distribution was qualitatively studied. In dogs with AF, the density of growth‐associated protein 43 (GAP43) immunopositivenerve fibers in the left atrium (LA), atrial septum (AS), and right atrium (RA) was significantly (19,454.31 ± 1,592.81 μm2/mm2 vs 1,673.41 ± 142.62 μm2/mm2P < 0.001, 3,931.26 ± 361.78 μm2/mm2 vs 1,614.20 ± 140. 41 μm2/mm2 P < 0.05 and 2,324.15 ± 1,123.77 μm2/mm2 vs 1,620.47 ± 189.05 μm2/mm2 P < 0.05, respectively) higher than the nerve density in control tissues. The density of (neuropeptide Y) NPY‐positive nerves in the, AS, and RA was (13,547.62 ± 2,983.37 μm2/mm2 vs 703.72 ± 287.52 μm2/mm2 P < 0.01, 2,689.22 ± 340.93 μm2/mm2 vs 651.7 ± 283.02 μm2/mm2 P < 0.01 and 1,574.70 ± 424.37 μm2/mm2 vs 580.42 ± 188.12 μm2/mm2 P < 0.001, respectively) higher than the nerve density in control tissues. At the same time, vasoactive intestinal polypeptide (VIP) positive nerve innervation shrank in dogs with AF. The density of VIP positive in LA, AS, and RA was statistically lower than the nerve density in control tissues, respectively. (110.48 ± 45.63μm2/mm2 vs 1679.32 ± 1020.34μm2/mm2 P < 0.01, 265.92 ± 52.51 μm2/mm2 vs 2602.68 ± 1257.16μm2/mm2 P < 0.001 and 609.56 ± 139.75μm2/mm2 vs 2771.68 ± 779.08μm2/mm2 P < 0.01, respectively) Conclusions: Combined with VIP‐ergic nerve denervation, significant nerve sprouting and NPY‐ergic nerve hyperinnervation are present in a canine model of sustained AF produced by prolonged atrial pacing.  相似文献   

15.
In the presence of a normal atrial systole and optimal AV delay, atrial kick contributes to a significant fraction of the stroke volume. This atrial contribution may be lost during atrial asystole or mismatch in the timing of atrial and ventricular contraction. A patient received atrial compartment operation for his chronic AF. Although the AF was successfully converted to sinus rhythm, the conduction from the right to left atrium was markedly delayed so that the left atrial and ventricular activations occurred almost simultaneously. This delay in left atrial activation resulted in impaired cardiac performance.  相似文献   

16.
The aim of this prospective study was to compare the long-term follow-up after transisthmic ablation of patients with preablation lone atrial flutter, coexistent AF, and drug induced atrial flutter to determine if postablation AF followed a different clinical course and displayed different predictors in these groups. The study evaluated 357 patients who underwent transisthmic ablation for typical atrial flutter. These were divided into four groups according to their preablation history. Group A included patients with typical atrial flutter and without preablation AF (n=120, 33.6%). Group B included patients with preablation AF and spontaneous atrial flutter (n=132, 37.0%). Group C patients had preablation AF and atrial flutter induced by treatment with IC drugs (propafenone or flecainide) (n=63, 17.6%) Group D included patients with preablation AF and atrial flutter induced by treatment with amiodarone (n=42, 11.8%). During a mean follow-up of 15.2 double dagger 10.6 months (range 6-55 months) AF occurred more frequently in groups B (56.1%) and C (57.1%) patients than in groups A (20.8%, P <0.0001) and D (31.0%, P <0.0001) patients. The results of multivariate analysis revealed that different clinical and echocardiographical variables were correlated with postablation AF occurrence in the different groups. Patients with atrial flutter induced by amiodarone have a significantly lower risk of postablation AF than patients with spontaneous atrial flutter and AF, and those with atrial flutter induced by IC drugs. Different clinical and echocardiographical variables predict postablation AF occurrence in different subgroups of patients.  相似文献   

17.
扩张型心肌病患者心房颤动的临床意义   总被引:3,自引:0,他引:3  
目的:探讨扩张型心肌病(DCM)伴发心房颤动(AF)的临床意义。方法:将19例DCM伴AF者与50例DCM无AF者的临床、超声心动图及心电图资料进行对比分析。结果:DCM并发AF者年龄老化〔(65±16)岁〕,心功能(NYHAⅢ级~Ⅳ级者78.95%)差,栓塞率(21.05%)和病死率(36.84%)均高(P<0.05或P<0.01);左室射血分数(0.28±0.09)、短轴缩短率(0.15±0.03)明显降低,心脏扩大发生率、室性心律失常及复合心律失常发生率高(P<0.05或P<0.01)。结论:DCM的AF发生与年龄、心力衰竭、心室扩大、心肌病变相关,AF是预后不良的指标。  相似文献   

18.
The most feared consequence of atrial fibrillation (AF) is thromboembolism, either to the brain causing stroke or to the non-cerebral circulation. Valvular atrial fibrillation (VAF) and non-valvular atrial fibrillation (NVAF) differ not only by morphological substrate of arrhythmia but also by the rate of thromboembolic complications, predisposing factors and destination of embolism. In the setting of VAF, there is a higher risk of thromboembolism and a higher prevalence of thrombus location within the body of the left atrium compared to NVAF. VAF is also associated with a proportionally higher propensity for non-cerebral thromboemboli than in NVAF. The distribution of non-cerebral thromboemboli appears to be similar in VAF and NVAF; however, more research needs to be done in this area, particularly with regard to VAF.  相似文献   

19.
甄晓闽  李东野 《浙江临床医学》2009,11(12):1262-1264
目的研究阵发性心房颤动患者自动复律后左心耳功能变化及其影响因素。方法应用经食管超声心动图检测38例阵发性房颤患者复律后当日和复律后第7天的左心耳血流最大排空速度,同时测定血浆心钠素、房颤持续时间、左房内径等其他指标,并与20例正常对照组作比较。结果阵发性房颤患者复律当日左心耳血流最大排空速度(35.95±5.48)cm/s,明显低于复律后1周时(63.03±5.64)cm/s及正常对照组(64.37±6.93)cm/s,复律后1周时与正常对照组差异无统计学意义;多因素回归分析显示房颤持续时间、心钠素是复律当13左心耳血流最大排空速度的独立影响因素。结论阵发性房颤存在左心耳功能顿抑,其严重程度同房颤持续时间及心钠素水平有关。  相似文献   

20.
The nature of localized atrial activation during atrial fibrillation was characterized in 34 patients following open heart surgery. Bipolar atrial electrograms (AEG) recorded in each patient with atrial fibrillation exhibited a myriad of sizes, shapes, polarities, amplitudes, and beat-to-beat intervals. On the basis of the AEG morphology and the nature of its baseline, we have classified the recordings into four Types. Type I was characterized by discrete AEG complexes separated by an isoelectric baseline free of perturbation, Type II by discrete AEG complexes but with perturbations of the baseline between complexes, Type III by AEGs which failed to demonstrate either discrete complexes or isoelectric intervals, and Type IV in which AEGs of Type III alternated with periods characteristic of Type I and/or Type II. In 22 patients, the AEGs were recorded a second time, and in 11 of these patients the type of atrial fibrillation changed between the first and second recording period. An atrial flutter-fibrillation pattern in the ECG was associated with a relatively ordered atrial activation pattern and a relatively slow atrial rate. Human atrial fibrillation is not an electrophysiologically homogeneous process when compared among different patients or ad seriatim in the same patient.  相似文献   

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