Relationships between paroxysmal atrial fibrillation,total oxidant status,and DNA damage

IntroductionStructural and electrophysiological changes play a critical role in the development of atrial fibrillation (AF). Although the pathophysiology of paroxysmal AF (PAF) has not been fully elucidated, oxidative stress (OS) and DNA damage appear to be important triggers. Thus far, no studies have investigated the relationships among total oxidant status (TOS), DNA damage, and PAF. The goal of this study was to assess TOS and DNA damage in patients with PAF.MethodsThis cross-sectional study included 56 patients with PAF and 31 healthy controls. OS was assessed based on TOS, total antioxidant capacity (TAC), and oxidative stress index (OSI). The level of DNA damage was assessed using 8-hydroxy-2′-deoxyguanosine (8-OHdG).ResultsThere were no significant differences between the groups in terms of baseline characteristics. However, patients with PAF had significantly higher high-sensitivity C-reactive protein (p=0.018), TOS (p=0.001), OSI (p=0.001), and 8-OHdG (p=0.019) levels, compared with the control group. Multivariate logistic regression analysis showed that serum TOS level (odds ratio: 1.608; 95% confidence interval [CI]: 1.188-2.176, p=0.002) was the only independent predictor of PAF. TOS ≥12.2 predicted PAF with a sensitivity of 82% and specificity of 76% (AUC: 0.785, 95% CI: 0.687-0.883, p<0.001).ConclusionWe found that TOS and DNA damage were significantly greater in patients with PAF than in the control group. Therefore, we propose that TOS and DNA damage can be used to detect patients at higher risk of AF.     

Efficacy of extended antrum ablation based on substrate mapping plus pulmonary vein isolation in the treatment of atrial fibrillation

Introduction and objectivesPulmonary vein isolation (PVI) technique has become the cornerstone of atrial fibrillation (AF) catheter ablation. The objective of this study was to assess the efficacy and safety of extended antrum ablation based on electrophysiological substrate mapping plus PVI in AF patients who underwent cryoballoon ablation.MethodsIn this observational study, a total of 121 paroxysmal AF patients and 80 persistent AF patients who did not achieve the procedure endpoint after cryoballoon ablation received extra extended antrum ablation (EAA) based on electrophysiological substrate mapping via radiofrequency ablation (EAA group). As a control group (PVI group), among paroxysmal AF and persistent AF patients, we conducted a propensity score-matched cohort, in whom only PVI was completed.ResultsThe average follow-up time was 15.27±7.34 months. Compared with PVI group, paroxysmal AF patients in the EAA group had a significantly higher rate of AF-free survival (90.1% vs. 80.2%, p=0.027) and AF, atrial flutter, or atrial tachycardia (AFLAT) -free rate survival (89.3% vs. 79.3%, p=0.031). Persistent AF patients in the EAA group also had a significantly higher rate of AF-free survival (90.0% vs. 75.0%, p=0.016) and AFLAT-free survival (88.8% vs. 75.0%, p=0.029) than PVI group. Complication rates did not significantly differ between both groups, in either paroxysmal AF or persistent AF patients.ConclusionOur findings demonstrate that extra extended antrum ablation based on electrophysiological substrate mapping is effective and safe. Moreover, the strategy can improve the outcome of AF cryoablation.     

Impact of catheter ablation for atrial fibrillation in patients with heart failure and left ventricular systolic dysfunction

Introduction and AimsCatheter ablation has been shown to improve left ventricular (LV) ejection fraction (LVEF) in patients with atrial fibrillation (AF) and heart failure (HF). Our aim was to assess the impact of AF ablation on the outcome of patients with HF and LV systolic dysfunction.MethodsWe performed a retrospective observational cohort study of all patients with HF and LVEF <50% and with no apparent cause for systolic dysfunction other than AF who underwent catheter ablation in a tertiary referral center between July 2016 and November 2018. The primary endpoint was a ≥5% improvement in LVEF. Secondary endpoints included improvement in New York Heart Association (NYHA) class and reduction in LV end-diastolic diameter (LVEDD) and left atrial diameter (LAD).ResultsOf 153 patients who underwent AF ablation in this period, 22 (77% male, median age 61 [IQR 54-64] years) fulfilled the inclusion criteria. Median follow-up was 11.1 months (IQR 6.1-19.0). After ablation, median LVEF increased from 40% (IQR 33-41) to 58% (IQR 55-62) (p<0.01), mean NYHA class improved from 2.35±0.49 to 1.3±0.47 (p<0.001), and median LAD and LVEDD decreased from 48.0 (IQR 43.5-51.5) mm to 44 (IQR 40-49) mm (p<0.01) and from 61.0 (IQR 54.0-64.8) mm to 55.0 (52.2-58.0) mm (p<0.01), respectively.ConclusionIn patients with HF and LV systolic dysfunction, AF ablation is associated not only with improved functional status but also with favorable structural remodeling, including improvement in LVEF and decreases in LAD and LVEDD.     

Outcomes of radiofrequency catheter ablation for persistent and long-standing persistent atrial fibrillation

ObjectiveTo assess one-year outcomes in patients with persistent and long-standing persistent atrial fibrillation (AF) treated by catheter ablation.MethodsA retrospective observational study was conducted of consecutive patients referred for catheter ablation of persistent or long-standing persistent AF between May 2016 and October 2018. Patients underwent two different ablation strategies: pulmonary vein isolation (PVI) plus complex fractionated atrial electrograms (CFAE) (from May 2016 to June 2017) or a tailored approach (from July 2017 to October 2018). The overall recurrence rate at one year was analyzed. The secondary endpoint was arrhythmia recurrence according to the type of AF (persistent vs. long-standing persistent AF) and according to the ablation strategy employed.ResultsDuring the study period, 67 patients were included (40% with long-standing persistent AF). During a mean follow-up of 16±6 months, 27% of the patients had arrhythmia recurrence. Patients with long-standing persistent AF had a higher recurrence rate than those with persistent AF (44.4% vs. 15%, p=0.006), while patients who underwent a tailored approach presented better outcomes than those undergoing PVI plus CFAE ablation (17.5% vs. 40.7%, p=0.024). Ablation strategy (HR 6.457 [1.399-29.811], p=0.017), time in continuous AF (HR 1.191 [1.043-1.259], p=0.010) and left atrial volume index (HR 1.160 [1.054-1.276], p=0.002) were independent predictors of arrhythmia recurrence.ConclusionCatheter ablation is an effective treatment for patients with persistent and long-standing persistent AF. Patients with persistent AF and those undergoing a tailored approach presented lower arrhythmia recurrence.     

Medium- and long-term outcome after a single second-generation cryoballoon ablation in patients with paroxysmal and persistent atrial fibrillation

Introduction and objectivesTo report medium- and long-term results following a single second-generation cryoballoon (CB2)-based ablation procedure in patients with paroxysmal (PAF) and persistent (PeAF) atrial fibrillation.MethodsA retrospective study was performed of consecutive patients undergoing a first CB2-based ablation procedure in a tertiary center. Cryoenergy was applied for 3 min if a time to effect <60 s was documented or 4 min otherwise, with a bonus application in cases of late isolation or suboptimal temperature. Follow-up was obtained from the regional health electronic records system and by telephone or personal interviews. Recurrence was defined as any atrial arrhythmia >30 s beyond a three-month blanking period. The clinical impact of recurrences was classified using a severity score.ResultsA total of 172 patients (134 PAF and 38 PeAF) were included, of whom 25 (14.5%) had structural heart disease and 120 (69.7%) had a normal or mildly dilated left atrium. Acute success was achieved in 167 (97.1%). After a median follow-up of 27 (14-41) months, 100 patients (58.1%) remained free of atrial arrhythmias (64.2% for PAF and 36.8% for PeAF, p=0.006). Left atrial size (p=0.05) and clinical presentation as PeAF (p=0.006) were predictors of recurrence. Of patients with recurrences, 11.1% did not require further therapies and an additional 16.7% had good control with antiarrhythmic drugs.ConclusionsA single CB2 procedure resulted in 58.1% of patients remaining free of atrial arrhythmias at 27-month follow-up. Conservative management was useful in 27.8% of patients with recurrences.     

Cardiac resynchronization therapy in patients with atrial fibrillation: A meta-analysis

Background and ObjectiveTo combine the results of the best scientific evidence in order to compare the effects of cardiac resynchronization therapy (CRT) in heart failure patients with atrial fibrillation (AF) and in sinus rhythm (SR) and to determine the effect of atrioventricular nodal ablation in AF patients.MethodsThe electronic databases PubMed, B-On and Cochrane CENTRAL were searched, and manual searches were performed, for randomized controlled trials and cohort studies up to November 2012. The endpoints analyzed were all-cause and cardiovascular mortality and response to CRT.ResultsWe included 19 studies involving 5324 patients: 1399 in AF and 3925 in SR. All-cause mortality was more likely in patients with AF compared to patients in SR (OR=1.69; 95% CI: 1.20–2.37; p=0.002). There were no statistically significant differences in cardiovascular mortality (OR=1.36; 95% CI: 0.92–2.01; p=0.12). AF was associated with an increased likelihood of lack of response to CRT (OR=1.41; 95% CI: 1.15–1.73; p=0.001). Among subjects with AF, ablation of the atrioventricular node was associated with a reduction in all-cause mortality (OR=0.42; 95% CI: 0.22–0.80; p=0.008), cardiovascular death (OR=0.39; 95% CI: 0.20–0.75; p=0.005) and the number of non-responders to CRT (OR=0.30; 95% CI: 0.10–0.90; p=0.03).ConclusionsThe presence of AF is associated with increased likelihood of all-cause death and non-response to CRT, compared to patients in SR. However, many patients with AF benefit from CRT. Atrioventricular nodal ablation appears to increase the benefits of CRT in patients with AF.     

Simple electrocardiographic markers for the prediction of paroxysmal atrial fibrillation in hyperthyroidism

BACKGROUND: Hyperthyroidism is a major cause of paroxysmal atrial fibrillation (AF). The purpose of this study was to evaluate the predictors of AF in the patients with clinical and subclinical hyperthyroidism. METHODS AND RESULTS: The study population consisted of four groups: group I (57 euthyroid healthy persons), group II (33 patients with subclinical hyperthyroidism), group III (69 patients with overt hyperthyroidism) and group IV (31 patients with overt hyperthyroidism and documented paroxysmal AF). The maximum P wave duration (P maximum) in group IV (114 +/- 8 ms) was significantly higher than group I (102 +/- 7 ms, p < 0.001), group II (106 +/- 7 ms, p < 0.001) and group III (108 +/- 9 ms, p0.005). The P wave dispersion (PWD) was measured as 46 +/- 9 ms in group IV and this was significantly higher than group I (29 +/- 8 ms, p < 0.001), group II (36 +/- 9 ms, p < 0.001) and grup III (38 +/- 8 ms, p = 0.001). The P maximum and PWD were higher in the patients with subclinical hyperthyroidism compared to healthy individuals. Univariate regression analysis revealed that age, P maximum and PWD, multivariate analysis showed that P maximum and PWD were significant predictors of paroxysmal AF. A PWD value of 37.5 ms separated group IV from others with a sensitivity of 90%, specificity of 85%, and positive predictive accuracy of 77%. CONCLUSION: Simply measuring P maximum and PWD values, we could identify the patients with high risk for the development of AF and these simple ECG parameters may help in clinical judgement to determine the requirement for treatment in the patients with subclinical hyperthyroidism.     

Echocardiographic assessment of atrial function in patients with hypertrophic cardiomyopathy with and without paroxysmal atrial fibrillation

Introduction and objectivesHypertrophic cardiomyopathy (HCM) is accompanied by pathophysiological changes that predispose to the development of atrial fibrillation (AF). This arrhythmia impacts negatively on the morbidity, mortality and quality of life of these patients. Our objective was to evaluate the behavior of left atrial function, by means of atrial strain (derived from speckle tracking) and volumetric analysis by three-dimensional echocardiography, in patients with HCM with paroxysmal AF.MethodWe analysed left atrial function in 53 patients with HCM, 25 of whom were paroxysmal AF carriers (mean age 61.7±9.9 years; 56% female) compared with 28 members of the control group (mean age 60.5±10 years; 53.6% female) who were matched especially for sex, age and other demographic data.ResultsIt was observed that patients with HCM and a history of paroxysmal AF had lower left atrial emptying fractions than individuals in the control group; and the active atrial emptying fraction was a factor independently associated with the presence of this arrhythmia (p=0.018; odds ratio=0.93). Moreover, we found a significant reduction of the left atrial strain in all its components in the total sample of patients, with no difference between the groups.ConclusionsMeasurements of atrial emptying fractions by three-dimensional echocardiography allowed differentiating patients with HCM with and without paroxysmal AF.     

Electrocardiographic P wave changes after thoracoscopic pulmonary vein isolation for atrial fibrillation

Background

Changes in P wave duration (PWD) and P wave area (PWA) have been described following catheter ablation for atrial fibrillation (AF). We hypothesize that video-assisted thoracoscopic pulmonary vein isolation (VATS-PVI) for AF results in decrease of PWD, PWA and P wave dispersion, which may resemble reverse electrical remodeling of the atrium after restoration of sinus rhythm.

Methods

VATS-PVI consisted of PVI and ganglionic plexus ablation in 29 patients (mean age, 59?±?7 years; 23 males; 17 paroxysmal AF) and additional left atrial lesions in patients with persistent AF. PWD and PWA were measured in ECG lead II, aVF and V2 of ECGs during sinus rhythm before, directly after, and 6 months postprocedure. P wave dispersion was derived from the 12 lead ECG.

Results

Prior to VATS-PVI, PWD did not correlate with left atrial size and no difference in left atrial size was found between patients with paroxysmal or persistent AF (p?=?0.27). Following VATS-PVI, PWD initially prolonged in all patients from 115?±?4.6 ms to 131?±?3.6 ms (p?<?0.01) but shortened to 99?±?3.2 ms after 6 months (p?<?0.01). PWA was 5.60?±?0.32 mV*ms at baseline, 6.44?±?0.32 mV*ms post-VATS-PVI (P?=?NS), and 5.40?±?0.28 mV*ms after 6 months (p?=?NS vs. baseline, p?<?0.05 vs. post-VATS-PVI). P wave dispersion decreased in the persistent AF group from baseline 67?±?3.3 to 64?±?2.5 ms post-VATS-PVI (p?=?0.30) and to 61?±?3.4 ms after 6 months (p?<?0.05).

Conclusions

PWD increases significantly directly after successful VATS-PVI in both groups. There was significant decrease in PWD after 6 months. Similarly, P wave dispersion decreased in the persistent group. These changes suggest an immediate procedure related effect, but the later changes may represent reverse electrical atrial remodeling following cessation of AF.     

New-onset atrial fibrillation during acute coronary syndromes: Predictors and prognosis

IntroductionNew-onset atrial fibrillation (AF) frequently complicates myocardial infarction, with an incidence of 6–21%.ObjectiveTo assess the predictors and prognosis of new-onset AF during acute coronary syndromes (ACS).MethodsWe performed a retrospective observational cohort study including 902 consecutive patients (mean age 64 years, 77.5% male) admitted to a single center over a two-year period, with a six-month follow-up.ResultsAF rhythm was identified in 13.8% patients, of whom 73.3% presented new-onset AF and 26.8% pre-existing AF. New-onset AF was more frequent in older (p<0.001) and hypertensive patients (p=0.001) and in those with previous valvular heart disease (p<0.001) and coronary artery bypass grafting (p=0.049). During hospitalization, patients with new-onset AF more often had respiratory infection (p=0.002) and heart failure (p<0.001), and higher values of NT-proBNP (p=0.007) and peak creatinine (p=0.001). On echocardiography they had greater left atrial (LA) diameter (p<0.001) and more frequent significant mitral regurgitation (p<0.001) and left ventricular ejection fraction (LVEF) ≤40% (p<0.001) and were less likely to have significant coronary lesions (p=0.009) or to have undergone coronary revascularization (p<0.001). In multivariate analysis, age (OR 1.06, p=0.021), LVEF ≤40% (OR 4.91, p=0.002) and LA diameter (OR 1.14, p=0.008) remained independent predictors of new-onset AF. Together with age, diabetes and maximum Killip class, this arrhythmia was an independent predictor of overall mortality (OR 3.11, p=0.032).ConclusionsAge, LVEF ≤40% and LA diameter are independent predictors of new-onset AF during ACS. This arrhythmia is associated with higher overall mortality (in-hospital and in follow-up).     

Electrophysiologic characteristics in initiation of paroxysmal atrial fibrillation from a focal area

OBJECTIVES: We investigated the electrophysiologic characteristics in the initiation of paroxysmal atrial fibrillation (PAF) from a focal area. BACKGROUND: The electrophysiologic characteristics in the initiation of PAF are still not clear. METHODS: The study group consisted of 77 patients (M/F = 65/12, age 66 +/- 12 years) with frequent episodes of PAF; we analyzed: 1) 15 cycle lengths of electrical activity before the onset of atrial fibrillation (AF); 2) coupling interval (CI) of the first ectopic beat just before the initiation of AF; and 3) the prematurity of an ectopic beat (prematurity index [PI] = CI/mean of preceding 15 cycle lengths). RESULTS: A total of 111 episodes of sustained AF were identified. Two patterns of AF initiation were observed: group I (59/111, 53%) included the episodes preceded by cycle length oscillation, and group II (52/111, 47%) included the episodes initiated by a single ectopic beat with preceding cycle length relatively constant. The PI of group I episodes was significantly greater than that of group II (0.41 +/- 0.12 vs. 0.34 +/- 0.10, p < 0.01). The CI (267 +/- 54 ms vs. 217 +/- 55 ms, p < 0.05), AF1 (194 +/- 36 ms vs. 153 +/- 37 ms, p < 0.05) and PI (0.49 +/- 0.13 vs. 0.37 +/- 0.11, p < 0.01) of the AF episodes from the superior vena cava (SVC) were significantly longer and greater than those of AF episodes from pulmonary veins (PVs). CONCLUSIONS: In patients with PAF originating from PVs or the SVC, two major initiating patterns were found. Moreover, the electrophysiologic characteristics in the initiation of AF originating from the SVC were also different from those of AF initiating from the PVs.     

Update on the efficacy of statins in primary and secondary prevention of atrial fibrillation

Atrial fibrillation is the most common arrhythmia in adults and its prevalence is growing rapidly. It has been shown that AF is associated with increased risk of heart failure, ischemic and hemorrhagic stroke, and mortality. Hence, there is growing interest among researchers in seeking preventive and therapeutic interventions regarding AF. In recent decades, it has been suggested that statins may decrease the incidence of AF and may also decrease its recurrence after cardioversion and catheter ablation. These effects are thought to be mediated by different mechanisms such as modulating inflammation, altering the properties of transmembrane ion channels, interfering with activation of matrix metalloproteinases, and acting on endothelial function. In this article, we review and update current knowledge about the role of statins in primary and secondary prevention of AF in general and specific populations.     

Effect of valsartan and ramipril on atrial fibrillation recurrence and P-wave dispersion in hypertensive patients with recurrent symptomatic lone atrial fibrillation

BackgroundThis study compared the effect of antihypertensive treatment with valsartan or ramipril on atrial fibrillation (AF) recurrence, on P-wave dispersion, (PWD) and on serum procollagen type I carboxy terminal peptide (PIP).MethodsA total of 369 mild hypertensive (systolic blood pressure (SBP) >140 and/or 90 < diastolic blood pressure (DBP) < 110 mm Hg) outpatients in sinus rhythm but with at least two episodes of AF in the previous 6 months were randomized to valsartan (n = 122), ramipril (n = 124), or amlodipine (n = 123) for 1 year. Clinic blood pressure (BP) and a 24-h electrocardiogram (ECG) were evaluated monthly. Patients were asked to report any episode of symptomatic AF and to perform an ECG as early as possible. PWD and serum PIP levels were evaluated before and after each treatment period.ResultsSBP and DBP were significantly reduced by the three treatments (P < 0.001). A total of 46 (47.4%) patients treated with amlodipine had a recurrence of AF as did 26 (27.9%) patients treated with ramipril (P < 0.01 vs. amlodipine) and 16 (16.1%) patients treated with valsartan (P < 0.01 vs. amlodipine and P < 0.05 vs. ramipril). The Kaplan-Meyer analysis showed a significant reduction of AF episodes in the valsartan group (P = 0.005 log-rank test) as well as in the ramipril group (P = 0.021), even if at a lesser degree. PWD values were significantly reduced by ramipril (-4.2 ms, P < 0.05) and even more by valsartan (-11.2 ms, P < 0.01), the difference being significant (P < 0.01). Serum PIP levels were reduced by ramipril (-49.7 mug, P < 0.001) and valsartan (-49.3 mug, P < 0.001).ConclusionsDespite similar BP lowering, valsartan and ramipril were more effective than amlodipine in preventing new episodes of AF, but the effect of valsartan was greater than that of ramipril. This could be related to the greater PWD reduction observed with valsartan.American Journal of Hypertension (2008). doi:10.1038/ajh.2008.217American Journal of Hypertension (2008); 21, 9, 1034-1039. doi 10.1038/ajh.2008.217.     

Increased serum interleukin-6 level as a predictive biomarker for atrial fibrillation: A systematic review and meta-analysis

BackgroundAtrial fibrillation (AF) is related to a higher risk of thromboembolic events and mortality. Some studies have demonstrated that the inflammatory biomarker interleukin-6 (IL-6) is associated with a higher risk of higher thrombosis in AF patients, but the real effect of IL-6 remains a controversy.MethodsWe conducted a systematic review and meta-analysis to investigate the association between IL-6 and thromboembolic events, as well as bleeding events, acute coronary syndrome (ACS) events and all-cause mortality in AF.ResultsA total of five studies involving 22 928 patients met our inclusion criteria for the systematic review. The higher level of IL-6 in AF patients is related to long-term thromboembolic events including stroke (RR 1.44, CI 95% 1.09-1.90, p=0.01). IL-6 meant a higher risk of long-term bleeding risk (RR 1.36, CI 95% 1.06-1.74, p=0.02), ACS risk (RR 1.81, CI 95% 1.43-2.30, p<0.001) and all-cause mortality (RR 2.35, CI 95% 2.09-2.65, p<0.001).ConclusionA higher level of IL-6 may predict a greater number of long-term thromboembolic events and bleeding events, ACS events and mortality in AF patients. Further studies such as the cut-off point of IL-6 need to be conducted in the future.     

The impact of malnutrition on atrial fibrillation recurrence post ablation

Background and aimsBoth malnutrition and atrial fibrillation (AF) are the major health problems in modern society. Only a few studies focused on the relationship between malnutrition and recurrence of atrial arrhythmias post AF ablation (AF recurrence), which used body mass index (BMI) as nutrition assessment tool. However, BMI can't credibly reflect body composition and has limitation in patients with water-sodium retention. In this study, we used controlling nutritional status score (CONUT score) and geriatric nutritional risk index (GNRI) to identify the malnutrition patients and explored the effect of malnutrition on AF recurrence.Methods and resultsThis retrospective study included 246 patients who underwent AF ablation. During a median 11-month follow-up, 77 patients (31.3%) experienced AF recurrence. The recurrence group had higher CONUT score (2.3 ± 1.5 vs. 0.9 ± 1.0, P < 0.001) and lower GNRI (99.9 ± 7.6 vs. 103.9 ± 5.6, P < 0.001). After balancing the traditional risk factors, both CONUT score (OR: 2.614, 95%CI: 1.831–3.731, P < 0.001) and GNRI (OR: 0.884, 95%CI: 0.828–0.944, P < 0.001) were the independent predictors for AF recurrence. Pre-ablation CONUT score ≥1 and GNRI≥95.66 are indicative of AF recurrence. Adding CONUT score or GNRI to the base prediction model for AF recurrence significantly improved the discrimination and calibration. However, adding BMI to the base prediction model did not improve the model performance.ConclusionsCONUT score and GNRI are ideal tools to evaluate the nutrition status of AF patients. Undernourished patients are more likely to suffer from AF recurrence. Improving nutrition status may be a potential target for reducing the postoperative recurrence rate.     

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.     

Why atrial fibrillation recurs in patients who obtained current ablation endpoints with longstanding persistent atrial fibrillation

Purpose

Although several techniques for modification of atrial fibrillation (AF) substrate, such as linear ablation and complex fractionated atrial electrograms (CFAEs) ablation, have been proposed for longstanding persistent AF (LS-AF) and improved the outcome, there was still a certain recurrence rate, even if current ablation endpoints of these techniques were completely achieved. The purpose of this study was to describe the determinants of recurrent AF in patients who obtained current ablation endpoints with LS-AF.

Methods and results

In all, 208 consecutive patients who obtained current ablation endpoints with LS-AF were studied. The current ablation endpoints were defined as complete pulmonary vein isolation, bidirectional block of lines, and disappearance of CFAEs. After a follow-up of 19.9?±?4.1 months, the patients were classified as AF recurrence group and non-AF recurrence group (including patients with sinus rhythm and atrial tachycardia), and 34 (16 %) patients were in the AF recurrence group. The patients in AF recurrence group had higher rates of right atrium (RA) enlargement (67.7 vs. 45.4 %, p?=?0.018) and ≥2 procedure times (58.8 vs. 27.0 %, p?<?0.001), longer AF duration (82.4?±?44.8 vs. 50.8?±?42.8 months, p?<?0.001), and larger left atrium (LA) diameter (49.4?±?6.2 vs. 46.5?±?5.3 mm, p?=?0.007). In the multivariate analysis, RA enlargement, ≥2 procedure times, and AF duration were independent predictors of AF recurrence.

Conclusion

RA enlargement, ≥2 procedure times, and AF duration played important roles in AF recurrence in patients who obtained current ablation endpoints. For these patients with AF recurrence who had already underwent ≥2 procedure times, enlarged RA may contribute to other AF foci and/or substrate, and the ablation strategy may be transformed from LA to RA in the next ablation procedures.     

Electrocardiographic predictors of early recurrence of atrial fibrillation

Background

Electrical cardioversion (ECV) is an effective method for restoring sinus rhythm after atrial fibrillation (AF). However, early recurrence of AF occurs in a significant number of patients after ECV. This study aimed to identify electrocardiographic (ECG) predictors of early AF recurrence after ECV.

Methods

A total of 272 patients with persistent AF undergoing successful ECV were consecutively enrolled in this study. We investigated clinical, echocardiographic, and ECG data. The 12-lead ECG parameters were measured during sinus rhythm right after ECV using a digital caliper. The early AF recurrence was defined as recurrence within 2 months.

Results

Of the 272 patients, 165 patients (60.7%) experienced an early AF recurrence. Maximum P-wave duration (PWD) in limb leads (OR: 1.086; 95% CI: 1.019–1.157; p = .012) and P-terminal force (PTF) in V₁ (OR: 1.019; 95% CI: 1.004–1.033; p = .011) were independent predictors of early AF recurrence after ECV. The optimal cutoff value of the maximum PWD in limb leads for predicting early AF recurrence was 134 ms, characterized by 90.3% sensitivity and 72.0% specificity. Likewise, the optimal cutoff value of PTF in V₁ was 50 ms × mm, characterized by 80.0% sensitivity and 64.5% specificity.

Conclusion

A longer PWD (>134 ms) and a larger PTF (>50 ms × mm) were useful predictors of early recurrence of AF after successful ECV in clinical practice. A more effective rhythm control therapy such as catheter ablation or rate control strategy rather than a repeat ECV should be considered.

     

Increased P-wave dispersion predicts recurrent atrial fibrillation after cardioversion

Atrial fibrillation (AF) will recur in a number of patients treated with cardioversion. Being able to identify reliable risk factors would be useful for making management decisions. P-wave dispersion (PWD) is an electrocardiographic measurement, which reflects a disparity in atrial conduction. P-wave dispersion has been shown to be increased in patients with paroxysmal AF. This pilot study aims to determine the role of PWD in predicting AF recurrence in patients who underwent elective cardioversion. Forty-five patients who were successfully cardioverted for persistent AF were included for study. Eighteen patients had a PWD greater than 80 ms; of these 13 had AF recurrence. Of the 25 patients with PWD less than 80 milliseconds, 12 had recurrent AF. P-wave dispersion values greater than 80 milliseconds were found more frequently in patients with AF recurrence (P = .05), supporting the use of this parameter in predicting return of AF. Larger studies are needed for further evaluation.     

Impacts of sinus rhythm maintenance with catheter ablation on exercise tolerance in patients with paroxysmal atrial fibrillation

Background

It has been recently reported that sinus rhythm (SR) maintenance with catheter ablation therapy improves exercise tolerance (ET) in patients with persistent atrial fibrillation (AF). However, it remains to be elucidated whether this is also the case for patients with paroxysmal AF (PAF).

Methods

We enrolled consecutive 54 patients with PAF (age; 63?±?10 [SD] years old, male/female 46/8) and 26 patients with persistent AF (non-PAF) (age; 57?±?12 [SD] years old, male/female 23/3) who underwent AF ablation without recurrence. ET and cardiac function were evaluated by cardio-pulmonary exercise test and ultrasound echocardiography before and 6 months after ablation.

Results

The parameters of cardiopulmonary exercise test were comparable between the 2 groups. When PAF group was divided into 2 groups according to the time since diagnosis, peak oxygen uptake (peak VO₂) before ablation was significantly lower in patients with PAF duration of more than 1 year (n =?26), compared with those with less than 1 year (n =?28) (18.1?±?3.7 vs 21.3?±?5.8 ml/kg/min, P =?0.022). At 6 months after SR maintenance without AF burden, peak VO₂ significantly improved in both PAF (19.8?±?5.1 to 22.0?±?4.8 ml/kg/min, P =?0.0001) and non-PAF (20.6?±?3.9 to 23.4?±?5.0 ml/kg/min, P?<?0.01). Furthermore, the improvement rate of peak VO₂ after successful ablation had a highly significant inverse relationship with peak VO₂ at baseline in patients with PAF (r =???0.48, P =?0.0003).

Conclusions

These results indicate that SR maintenance with ablation improves ET in patients with PAF, especially in those with reduced ET.