Relation of C-reactive protein to long-term risk of recurrence of atrial fibrillation after electrical cardioversion

The aim of this study is to assess the role of C-reactive protein (CRP) in predicting long-term risk of atrial fibrillation (AF) recurrence after electrical cardioversion. CRP levels are associated with the presence of AF and failure of electrical or pharmacologic cardioversion, but no previous study has assessed their predictive role in long-term follow-up after successful electrical cardioversion. One hundred two consecutive patients (age 67 +/- 11 years; 58 men) with nonvalvular persistent AF who underwent successful biphasic electrical cardioversion were studied. High-sensitivity CRP was measured immediately before cardioversion. Follow-up was performed up to 1 year in all cases. Patients were divided into 4 groups according to CRP quartiles. Patients in the lowest CRP quartile (<1.9 mg/L) had significantly lower rates of AF recurrence (4% vs 33% at 3 months in the other 3 groups combined, p = 0.007, and 28% vs 60% at 1 year, p = 0.01). The 4 groups were similar in age, gender, ejection fraction, and left atrial size. Survival analysis confirmed that patients in the lowest CRP quartile had a lower recurrence rate (p = 0.02). Cox regression analyses using age, gender, hypertension, diabetes, ejection fraction, left atrial diameter, use of antiarrhythmic drugs, angiotensin-converting enzyme inhibitors or angiotensin II antagonists, and statins, and CRP quartiles as covariates showed that only CRP was independently associated with AF recurrence during follow-up (hazard ratio 4.98, 95% confidence interval 1.75 to 14.26, p = 0.003). In conclusion, low CRP is associated with long-term maintenance of sinus rhythm after cardioversion for nonvalvular AF.     

C反应蛋白对心房颤动药物复律后复发的远期预测价值

目的研究基线C反应蛋白(CRP)水平与心房颤动(简称房颤)药物复律后远期复发之间的关系。方法 71例持续性房颤患者使用胺碘酮复律,并且接受胺碘酮维持窦性节律的治疗,复律成功43例。根据基线CRP水平将复律成功的43例分为2组(0~4 mg/L组、≥4 mg/L组)。随访观察3年后,了解基线CRP水平与房颤复发间的关系。结果随访期内,有32(74.7%)例房颤复发。CRP 0~4 mg/L组,有12(12/21,57.1%)例房颤复发,CRP水平≥4 mg/L组有20例(20/22,90.9%)房颤复发,两组比较差异有显著性(P0.05)。Cox相关分析表明CRP基线水平与房颤复发相关(风险比6.09;95%可信区间3.15~12.60)。结论在预测房颤药物复律后房颤复发上,基线CRP水平可能有预测价值。     

High sensitivity C-reactive protein: a predictor for recurrence of atrial fibrillation after successful cardioversion

Atrial fibrillation (AF) is often associated, more or less indirectly, with an inflammatory acute or chronic process. So it is probable that the inflammation could contribute to the genesis and the perpetuation of this dysrhythmia. Phlogistic test indexes in patients (pts) with AF will be positive and have prognostic significance in patients treated with electrical cardioversion with restoration of a sinus rhythm. We evaluated 106 pts affected by AF of recent onset without known cardiovascular disease. We measured the plasma concentration of C-reactive protein (CRP) through a high sensibility method, in addition to routine blood samples. We perfomed an ECG 1 week and a Holter ECG monitoring 1 and 6 months after the electrical cardioversion. The CRP values were high (5.8 ± 10.7 U/L), with values above the normal range in 60 pts. After electrical cardioversion, we obtained restoration of sinus rhythm in all the patients. One week after cardioversion, 85 pts (80%) were in sinus rhythm, while after 6 months 60 pts (56%) maintained a sinus rhythm. In total 46 (43%) patients had a recurrence of atrial fibrillation within 6 months, and 41 of these 46 patients (89%) had elevated values of CRP (P < 0.001 with respect to the patients who maintained a sinus rhythm). 18/21 patients (86%) with an AF relapse in the first week and 23/25 patients (92%) with AF recurrences at 6 months later had elevated values of CRP. The patients with AF may have elevated values of CRP, and the assessment of this increase may be predictive of early relapses of AF after electrical cardioversion.     

Does flecainide regain its antiarrhythmic activity after electrical cardioversion of persistent atrial fibrillation?

OBJECTIVES: The purpose of this study was to evaluate the hypothesis that presumed reversion of electrical remodeling after cardioversion of atrial fibrillation (AF) restores the efficacy of flecainide. BACKGROUND: Flecainide loses its efficacy to cardiovert when AF has been present for more than 24 hours. Most probably, the loss is caused by atrial electrical remodeling. Studies suggest electrical remodeling is completely reversible within 4 days after restoration of sinus rhythm (SR). METHODS: One hundred eighty-one patients with persistent AF (median duration 3 months) were included in this prospective study. After failure of pharmacologic cardioversion by flecainide 2 mg/kg IV (maximum 150 mg in 10 minutes) and subsequent successful electrical cardioversion, we performed intense transtelephonic rhythm monitoring three times daily for 1 month. In case of AF recurrence, a second cardioversion by flecainide was attempted as soon as possible. RESULTS: AF recurred in 123 patients (68%). Successful cardioversion by flecainide occurred only when SR had been maintained for more than 4 days (7/51 patients [14%]). Failure to cardiovert was associated with a prolonged duration of the recurrent AF episode and concurrent digoxin use. Multivariate logistic regression confirmed that successful cardioversion was determined by digoxin use (odds ratio [OR] 0.093, P = .047) and by the interaction between the duration of SR and the (inverse) duration of recurrent AF (OR 6.499, P < .001). When flecainide was administered within 10 hours after AF onset and the duration of SR was greater than 4 days, the success rate was 58%. CONCLUSIONS: Flecainide recovers its antiarrhythmic action after cardioversion of AF. However, successful pharmacologic cardioversion occurs only after SR has lasted at least 4 days and is expected only for recurrences having duration of a few hours. Immediate pharmacologic cardioversion of AF recurrence may be a worthwhile strategy for management of persistent AF.     

高敏C反应蛋白对心房颤动患者电复律后再发的预测

目的通过检测患者血清高敏C反应蛋白(hs-CRP)水平,探讨其对非瓣膜性心房颤动(房颤)患者电复律后再发的预测价值。方法非瓣膜性持续性房颤经电复律的患者126例,男性73例,女性53例,平均年龄(64±10)岁,在电复律前,测定hs-CRP,依据hs-CRP水平将患者分为3组,低水平组41例,hs-CRP<2.0 mg/L,中等水平组47例,hs-CRP 2.0~3.0 mg/L,高水平组38例,hs-CRP>3.0 mg/L。随访6个月,复查24 h动态心电图,观察房颤的复发情况。结果3组在年龄、房颤时间、左心房大小、心功能方面比较差异无统计学意义(P>0.05)。6个月随访时,低水平组房颤的复发率7.3%,远低于中等水平组的21.3%和高水平组的36.8%,差异有统计学意义(P<0.001),中等水平组房颤的复发率低于高水平组(P<0.05),Cox回归分析显示,hs-CRP水平与电复律后,房颤再发呈显著正相关(OR=3.22,95%CI:1.58~13.41)。结论非瓣膜性持续性房颤电复律后,hs-CRP水平与房颤的中期再发有关,hs-CRP可以作为房颤电复律后再发的独立预测因子。     

Does Sinus Rhythm Beget Sinus Rhythm? Effects of Prompt Cardioversion on the Frequency and Persistence of Recurrent Atrial Fibrillation

Recent clinical and experimental studies have demonstrated that atrial fibrillation (AF) alters the electrical and mechanical remodeling of the atrium, which subsequently promote the maintenance and recurrence of AF. If atrial remodeling can be prevented with prompt and repeated cardioversion, the likelihood of AF recurrence may be reduced. Recent clinical studies have demonstrated that the strategies of transesophageal echocardiography facilitated early cardioversion and early repeated cardioversion may be clinically valuable in some patients who have persistent AF and recurrence of arrhythmia after the initial cardioversion. Furthermore, the use an implantable atrial defibrillator (IAD) for early repeated device-based cardioversion to maintain sinus rhythm appears to be safe and clinically feasible. Early cardioversion by IAD reduces AF burden, reverses atrial remodeling and prevents subsequent AF recurrence in selected patients without structural heart disease implanted with this device, indicating possible "sinus rhythm begets sinus rhythm". Despite encouraging initial observations, further long-term clinical studies in a larger patient population are needed to confirm this finding. Furthermore, whether the use of IAD in the fully automatic mode to provide immediate termination of AF episodes could intensify the potential beneficial effect and the clinical efficacy of this approach in patients with structural heart disease needs to be evaluated.     

Time to Cardioversion of Recurrent Atrial Arrhythmias After Catheter Ablation of Atrial Fibrillation and Long‐Term Clinical Outcome

Introduction: It is unclear whether early restoration of sinus rhythm in patients with persistent atrial arrhythmias after catheter ablation of atrial fibrillation (AF) facilitates reverse atrial remodeling and promotes long‐term maintenance of sinus rhythm. The purpose of this study was to determine the relationship between the time to restoration of sinus rhythm after a recurrence of an atrial arrhythmia and long‐term maintenance of sinus rhythm after radiofrequency catheter ablation of AF. Methods and Results: Radiofrequency catheter ablation was performed in 384 consecutive patients (age 60 ± 9 years) for paroxysmal (215 patients) or persistent AF (169 patients). Transthoracic cardioversion was performed in all 93 patients (24%) who presented with a persistent atrial arrhythmia: AF (n = 74) or atrial flutter (n = 19) at a mean of 51 ± 53 days from the recurrence of atrial arrhythmia and 88 ± 72 days from the ablation procedure. At a mean of 16 ± 10 months after the ablation procedure, 25 of 93 patients (27%) who underwent cardioversion were in sinus rhythm without antiarrhythmic therapy. Among the 46 patients who underwent cardioversion at ≤30 days after the recurrence, 23 (50%) were in sinus rhythm without antiarrhythmic therapy. On multivariate analysis of clinical variables, time to cardioversion within 30 days after the onset of atrial arrhythmia was the only independent predictor of maintenance of sinus rhythm in the absence of antiarrhythmic drug therapy after a single ablation procedure (OR 22.5; 95% CI 4.87–103.88, P < 0.001). Conclusion: Freedom from AF/flutter is achieved in approximately 50% of patients who undergo cardioversion within 30 days of a persistent atrial arrhythmia after catheter ablation of AF.     

Clinical evaluation of a policy of early repeated internal cardioversion for recurrence of atrial fibrillation

INTRODUCTION: The clinical value of cardioversion (CV) of persistent atrial fibrillation (AF) is limited by the high rate of early AF recurrence, which may be related to the persistence of atrial electrical remodeling. We examined the hypothesis that the likelihood of maintaining sinus rhythm after CV of persistent AF is significantly enhanced by a policy of early repeated CV. METHODS AND RESULTS: Fifty-nine patients with persistent AF underwent internal CV (CV 1). Those patients cardioverted were monitored with daily transtelephonic ECG. In the event of AF recurrence, these patients were admitted rapidly for repeat CV (CV 2) and, if further recurrence occurred, a third CV (CV 3) was performed. Daily ECG monitoring was continued until 1 month of sinus rhythm was maintained or a total of three CVs were performed. Of the 59 patients undergoing CV 1, 43 were discharged in sinus rhythm and 29 subsequently had AF recurrence during monitoring. Twenty-three of these underwent CV 2 and 11 of these underwent CV 3. Of those having repeated CVs, only 4 patients maintained sinus rhythm for 1 month (3 after CV 2 and 1 after CV 3). The remaining patients had repeated AF recurrence during the monitoring period. Mean time from AF recurrence to CV 2 was 20+/-13 hours and from AF recurrence to CV 3 was 13+/-7.2 hours. Atrial effective refractory periods increased from 189+/-16 msec at CV 1 to 215+/-18 msec at CV 3 (P < 0.05), indicating reversal of atrial electrical remodeling during this period. CONCLUSION: A policy of early repeated CVs for AF recurrence has very limited clinical value despite evidence of reversal of atrial electrical remodeling. The time between AF recurrence and repeat CV may need to be reduced further if such a policy is to succeed.     

Echocardiographic and Electrocardiographic Predictors for Atrial Fibrillation Recurrence Following Cardioversion

Introduction: Identification of suitable candidates for cardioversion currently is not based on individual electrical and mechanical atrial remodeling. Therefore, this study analyzed the meaning of atrial fibrillatory rate obtained from the surface ECG (as a measure of electrical remodeling) and left atrial size (as measure of mechanical remodeling) for prediction of early atrial fibrillation (AF) recurrence following cardioversion.
Methods and Results: Forty-four consecutive patients (26 men and 18 women, mean age 62 ± 11 years, no antiarrhythmic medication at baseline) with persistent AF were studied. Fibrillatory rate was obtained from high-gain, high-resolution surface ECG using digital signal processing (filtering, QRST subtraction, Fourier analysis) before electrical cardioversion. Univariate and multivariate regression analysis revealed larger systolic left atrial area (Beta = 0.176, P = 0.031) obtained by precardioversion echocardiogram from the apical four-chamber view and higher atrial fibrillatory rate (Beta = 0.029, P = 0.021) to be independent predictors for AF recurrence (n = 13). Stratification based on the regression equation (electromechanical index [EMI]= 0.176 systolic left atrial area + 0.029 fibrillatory rate − 17.674) allowed identification of groups at low, intermediate, or high risk. No patient with an EMI < −1.85 had early AF recurrence, as opposed to 78% with an EMI > −0.25. Intermediate results (40% recurrence rate) were obtained when the calculated EMI ranged between −1.85 and −0.25 (P < 0.001).
Conclusion: Fibrillatory rate obtained from the surface ECG and systolic left atrial area obtained by echocardiography may predict early AF recurrence in patients with persistent AF. These parameters might be useful in identifying candidates with a high likelihood of remaining in sinus rhythm after cardioversion. (J Cardiovasc Electrophysiol, Vol. 14, pp. S162-S165, October 2003, Suppl.)     

One-year outcome of cardioversion of atrial fibrillation in patients with mitral stenosis after percutaneous balloon mitral valvuloplasty

Our objectives were to study the success rate of electrical cardioversion after percutaneous balloon mitral valvuloplasty (PBMV) in patients with symptomatic moderate-to-severe mitral stenosis and atrial fibrillation (AF) and the maintenance rate of sinus rhythm for < or =1 year. We studied patients with mitral stenosis and AF who were scheduled for PBMV. Electrical cardioversion was performed 1 month after PBMV. Amiodarone 200 mg/day was started the day after PBMV. The primary outcomes studied were the rate of successful cardioversion and the maintenance rate of sinus rhythm at 12 months. Of 272 patients scheduled for PBMV, 70 were enrolled. The average age was 45 +/- 10 years. The average mitral valve area was 0.82 +/- 0.22 cm(2). Cardioversion was successful in 50 patients (71%). Logistic regression analysis revealed that left atrial size and associated aortic valvular disease were predictors of successful cardioversion. Of the 50 patients with successful cardioversion, AF recurred in 24 (48%). An increased left atrial diameter was the only factor associated with AF recurrence at 12 months. In conclusion, good candidates for cardioversion after PBMV were those with a left atrial diameter of <60 mm and no associated aortic valvular disease -- approximately 43% of patients with AF scheduled for PBMV. In this group, about 2/3 were in sinus rhythm at 12 months after cardioversion.     

Reverse atrial electrical remodelling following atrial defibrillation as determined by signal-averaged ECG

BACKGROUND: Following successful cardioversion for atrial fibrillation (AF), the rate of early recurrence remains high. Analysis of the signal-averaged electrocardiogram of the P wave has been proposed as a noninvasive method of predicting those at risk of recurrence. PURPOSE: To determine the change in signal-averaged P wave duration (SAPWD) following cardioversion from AF, and to determine whether SAPWD is associated with the risk of recurrence. METHODS: SAPWD was determined in 76 patients immediately following successful electrical cardioversion and three days later. Patients were then followed clinically for one year. RESULTS: Recurrent AF was observed in 32 of 76 patients at 90 days following cardioversion. There was no difference in SAPWD immediately following cardioversion (158+/-28 ms versus 164+/-31 ms, P=NS) or three days following cardioversion (152+/-24 ms versus 158+/-36 ms, P=0.4) in patients with and without recurrent AF. There was, however, a significant decrease in the SAPWD during the first three days following cardioversion in the patients who remained in sinus rhythm (158+/-28 ms initially versus 152+/-24 ms on day three, P=0.009). Among the patients with recurrent AF, the decrease was smaller and not statistically significant (161+/-30 ms versus 158+/-36 ms, P=0.3). CONCLUSION: Shortening of the SAPWD occurs following atrial defibrillation in patients who maintain sinus rhythm at 90 days. This provides evidence for reverse atrial electrical remodelling and its association with the maintenance of sinus rhythm.     

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.     

Characteristics and significance of very early recurrence of atrial fibrillation after catheter ablation

Very Early Recurrence of AF. Introduction: Early restoration of sinus rhythm following ablation of atrial fibrillation (AF) facilitates reverse atrial remodeling and improves the long‐term outcome. The purpose of this study was to determine the predictors and outcome in patients with very early AF recurrences (< 2 days). Methods and Results: Ablation was performed in 339 consecutive AF patients (paroxysmal AF = 262). Biatrial voltage was mapped during sinus rhythm. If recurrent AF occurred within 2 days following the ablation, electrical cardioversion was performed to restore sinus rhythm. Very early recurrences of AF occurred in 39 (15%) patients with paroxysmal AF and 26 (34%) with nonparoxysmal AF. Patients with very early recurrence had a higher incidence of nonparoxysmal AF (40% vs 18.6%, P< 0.001), requirement of electrical cardioversion during procedure, larger left atrial (LA) diameter (43 ± 7 vs 39 ± 6 mm, P< 0.001), lower left ventricular ejection fraction (54 ± 10% vs 59 ± 7, P< 0.001), longer procedural time, and lower LA voltage (1.5 ± 0.7 vs 1.9 ± 0.8 mV, P< 0.001). A multivariate analysis revealed that the independent predictors of a very early recurrence were a longer procedural time and lower LA voltage. During a follow‐up of 13 ± 5 months, a very early recurrence did not predict the long‐term outcome of a single procedure recurrence in the patients with paroxysmal AF, but was associated with a late recurrence in the nonparoxysmal AF patients. Conclusion: Very early recurrence occurred in patients with paroxysmal AF is not associated with long‐term recurrence. Nonparoxysmal AF is an independent predictor of late recurrence of AF in patients with very early recurrence. (J Cardiovasc Electrophysiol, Vol. pp. 1‐6)     

Effect of candesartan and various inflammatory markers on maintenance of sinus rhythm after electrical cardioversion for atrial fibrillation

Inflammatory markers, their relation to maintenance of sinus rhythm after electrical cardioversion for atrial fibrillation (AF), and the effect of candesartan were investigated in a double-blind placebo-controlled study (CAPRAF). One hundred seventy-one patients with persistent AF were randomly assigned to receive candesartan 8 mg/day or placebo for 3 to 6 weeks before and candesartan 16 mg/day or placebo for 6 months after electrical cardioversion. Serum levels of high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-alpha, interleukin-6, P-selectin, E-selectin, CD-40 ligand, and vascular cell adhesion molecule-1 were measured at baseline and end of study. Compared with patients with a relapse of AF, patients still in sinus rhythm at 6 months after cardioversion (n = 40) had lower baseline hs-CRP and E-selectin levels: median 2.36 mg/L (25th, 75th percentiles 1.28, 4.09) versus 3.44 mg/L (25th, 75th percentiles 1.66, 6.05, p = 0.031) and 32 ng/ml (25th, 75th percentiles 23, 42) versus 37 ng/ml (25th, 75th percentiles 28, 51, p = 0.042), respectively. Neither sustained sinus rhythm for 6 months nor treatment with candesartan had an impact on measured concentrations of markers of inflammation. In conclusion, low hs-CRP and E-selectin at baseline were associated with maintenance of sinus rhythm after electrical cardioversion.     

Use of enalapril to facilitate sinus rhythm maintenance after external cardioversion of long-standing persistent atrial fibrillation. Results of a prospective and controlled study.

AIMS: This study aimed to assess whether enalapril could improve cardioversion outcome and facilitate sinus rhythm maintenance after conversion of chronic atrial fibrillation (AF). METHODS AND RESULTS: Patients with chronic AF for more than 3 months were assigned to receive either amiodarone (200mg orally 3 times a day; group I: n=75) or the same dosage of amiodarone plus enalapril (10mg twice a day; group II: n=70) 4 weeks before scheduled external cardioversion. The end-point was the time to first recurrence of AF. In 125 patients (86.2%), AF was converted to sinus rhythm. Group II had a trend to a trend to a lower rate of immediate recurrence of AF than group I did (4.3% vs 14.7%, P=0.067). Kaplan-Meier analysis demonstrated a higher probability of group II remaining in sinus rhythm at 4 weeks (84.3% vs 61.3%, P=0.002) and at the median follow-up period of 270 days (74.3% vs 57.3%, P=0.021) than in group II. CONCLUSIONS: The addition of enalapril to amiodarone decreased the rate of immediate and subacute arrhythmia recurrences and facilitated subsequent long-term maintenance of sinus rhythm after cardioversion of persistent AF.     

Recurrence of atrial fibrillation after internal cardioversion of persistent atrial fibrillation: prognostic importance of electrophysiologic parameters.

BACKGROUND: The purpose of this study was to determine whether the extent of atrial electrical remodeling affects the recurrence of atrial fibrillation (AF) after cardioversion of persistent AF (PAF). METHODS AND RESULTS: Internal atrial cardioversion was performed in 47 patients with PAF. The right atrial monophasic action potential duration (RA-MAPD) at pacing cycle lengths (PCLs) of 800-300 ms and P wave signal-averaged electrocardiogram were recorded after cardioversion. Bepridil (150-200 mg/day) and carvedilol (10 mg/day) were administered to all patients after cardioversion. Of the 47 patients, 20 had recurrent AF within 3 months. No relation was observed between age, left atrial dimension, left ventricular ejection fraction, and AF recurrence. The AF duration was significantly longer (p<0.05) and RA-MAPD at PCLs of 800 to 300 ms were significantly shorter (p<0.05) in patients with AF recurrence than in those without recurrence. The mean slope of the RA-MAPD for PCLs between 600 and 300 ms did not differ between the patients with and without AF recurrence. The filtered P-wave duration (FPD) was significantly longer in the patients with AF recurrence than in those without (p<0.05). Multivariate analysis also showed that the RA-MAPD at a PCL of 300 ms and FPD were predictors of AF recurrence (RAMAPD: p=0.038; FPD: p=0.052). CONCLUSION: These results suggest that electrical remodeling related to the repolarization and depolarization may be the main contributors to early AF recurrence after cardioversion under the administration of bepridil and carvedilol.     

A randomized comparison of external and internal cardioversion of chronic atrial fibrillation.

BACKGROUND. Delivery of shocks within the right atrium has been reported to be more effective than conventional external shocks in converting atrial fibrillation (AF), but these two cardioversion techniques have never been compared prospectively. The purpose of this study was to compare the efficacies of external and internal cardioversion in patients with chronic AF unresponsive to prior attempts at electrical and/or pharmacological cardioversion. Low-dose amiodarone was used in all patients after cardioversion to suppress recurrences of AF. METHODS AND RESULTS. One hundred twelve patients with AF of at least 1 month in duration were randomly assigned to undergo external cardioversion with 300-360-J shocks or internal cardioversion with 200-300-J shocks delivered through a standard electrode catheter within the right atrium. The patients were treated with amiodarone (200 mg/day 5-7 days/week) for 1 month before electrical cardioversion and afterward if the cardioversion was successful. The patients were evaluated at regular intervals during 1 year of follow-up. The efficacy of internal cardioversion was significantly greater than that of external cardioversion (91% versus 67%, p = 0.002). The only variable that was associated with the outcome of cardioversion was body weight. Among patients in whom sinus rhythm was restored, AF recurred as often after internal and external cardioversion; at 1 year of follow-up, 37% of patients in whom external or internal cardioversion had been effective were still in sinus rhythm. Patients who had undergone an attempt at electrical cardioversion before entry into this study were less likely to remain in sinus rhythm after cardioversion. The only complications of cardioversion were one instance of cerebral thromboembolism after external cardioversion and one instance of transient pulmonary edema after internal cardioversion. Therapy with amiodarone was discontinued because of an adverse drug effect in only three patients. CONCLUSIONS. Internal cardioversion is more effective than external cardioversion in restoring sinus rhythm and is as safe as external cardioversion in patients with chronic AF. The recurrence rate of AF is the same after both types of cardioversion. If conventional electrical cardioversion is ineffective, internal cardioversion should be attempted. The combination of low-dose amiodarone and external or internal cardioversion may result in maintaining sinus rhythm long-term in patients with refractory AF.     

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.     

Effect of verapamil on immediate recurrence of atrial fibrillation

INTRODUCTION: The purpose of this study was to assess the effect of verapamil on immediate recurrences of atrial fibrillation occurring after successful electrical cardioversion. METHODS AND RESULTS: The effect of verapamil on the recurrence of atrial fibrillation within 5 minutes after successful transthoracic cardioversion was assessed in 19 (5%) of 364 patients undergoing electrical cardioversion. The mean duration of atrial fibrillation was 4.44+/-3.0 months. In the 19 patients, cardioversion was successful after each of three consecutive cardioversion attempts per patient; however, atrial fibrillation recurred 0.4+/-0.3 minutes after cardioversion. Verapamil 10 mg was administered intravenously and a fourth cardioversion was performed. Cardioversion after verapamil was successful in each patient, and atrial fibrillation did not recur in 9 (47%) of 19 patients (P < 0.001 vs before verapamil). In the remaining 10 patients in whom atrial fibrillation recurred, the duration of sinus rhythm was significantly longer compared with before verapamil (3.6+/-2.4 min, P < 0.001). The density of atrial ectopy occurring after cardioversion was significantly less after verapamil (21+/-14 ectopic beats per min) compared with before verapamil (123+/-52 ectopic beats per min, P < 0.001). CONCLUSION: Among patients with immediate recurrence of atrial fibrillation after electrical cardioversion, acute calcium channel blockade by verapamil reduces recurrence of atrial fibrillation and extends the duration of sinus rhythm.     

心房颤动电复律的相关因素

目的分析影响心房颤动电复律成功的因素。方法根据房颤患者62例电复律是否成功,分为复律成功组和失败组。比较两组在性别、年龄、并发冠心病、高血压病和瓣膜性心脏病、左心房内径、左心室舒张末期内径、左心室射血分数、C反应蛋白（CRP）水平的差异。CRP检测:所有患者于入院后/入组后第2天常规空腹抽血,采用免疫比浊法测定高敏感CRP（hs-CRP）。结果与转复成功组比较,转复失败组年龄大（P<0.05）,左心房内径大（P<0.05）,并发瓣膜性病变比例高（P<0.05）,房颤持续时间长（P<0.05）,hs-CRP水平高（P<0.05）。经多因素分析,hs-CRP水平OR为2.1（95%CI1.4-3.2,P<0.01）、左房直径OR为1.8（95%CI1.2-2.2,P<0.01）和房颤持续时间OR为2.8（95%CI1.6-4.0,P<0.01）。结论hs-CRP、左房直径及房颤持续时间是影响房颤电复律成功的独立预测因素。