Bi-directional block is superior to non-inducibility in predicting freedom from atrial fibrillation after pulmonary vein isolation

BackgroundThere is variability in the endpoints used with the different approaches to pulmonary vein (PV) isolation. Elimination of PVP recorded inside the targeted PV antrum indicates inlet block and is considered the 1st indicator of a successful PV isolation, however this may not be sufficient to predict non recurrence of AF.AimTo compare the efficacy of two end points, pulmonary vein (PV) entrance block with non-inducibility (NI) Vs achieving PV bi-directional (BD) block in terms of freedom of AF after PV isolation (PVI) for paroxysmal/persistent atrial fibrillation (AF).MethodWe included 58 consecutive patients (pts) who underwent PVI for symptomatic AF. In all pts, the end point of ablation was abolishing PV potentials (PVP) in the PVs followed by testing for bidirectional block (defined by both loss of PVP and failure to conduct to the LA by pacing at 10 mA and from 10 bipolar pairs of electrodes on a circular catheter positioned at the entrance of the PV) and/or NI of AF (by burst atrial pacing).ResultsBidirectional block was achieved in 40 patients (69%) while Non inducibility was achieved in 36 (58.5%) patients with an overlap of achieving both endpoints in 18 (31%) patients. Over a follow up period of 17 ± 11 months, 34 pts (85%) in group I Vs 22 (62%) in group II were free of AF. Correlation showed significant relation between BD block (OR = 8.07, P = 0.004) Vs NI of AF post-PVI (OR = 2.8, P = 0.095) in predicting freedom from AF at follow up.ConclusionAchieving BD block improves results and may predict maintenance of sinus rhythm more than NI of AF after PVI. It can be used as an electrophysiological endpoint alternative to or in conjunction with non inducibility in AF ablation procedures.     

Ablation of persistent atrial fibrillation based on high density voltage mapping and complex fractionated atrial electrograms: A randomized controlled trial

Introduction:Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) catheter ablation. However, a PVI alone has been considered insufficient for persistent AF. This study aimed to evaluate the efficacy of persistent AF ablation targeting complex fractionated atrial electrogram (CFAE) areas within low voltage zones identified by high-resolution mapping in addition to the PVI.Methods:We randomized 50 patients (mean age 58.4 ± 9.5 years old, 86.0% males) with persistent AF to a PVI + CFAE group and PVI only group in a 1:1 ratio. CFAE and voltage mapping was performed simultaneously using a Pentaray Catheter with the CARTO3 CONFIDENSE module (Biosense Webster, CA, USA). The PVI + CFAE group, in addition to the PVI, underwent ablation targeting low voltage areas (<0.5 mV during AF) containing CFAEs.Results:The mean persistent AF duration was 24.0 ± 23.1 months and mean left atrial dimension 4.9 ± 0.5 cm. In the PVI + CFAE group, AF converted to atrial tachycardia (AT) or sinus rhythm in 15 patients (60%) during the procedure. The PVI + CFAE group had a higher 1-year AF free survival (84.0% PVI + CFAE vs 44.0 PVI only, P = .006) without antiarrhythmic drugs. However, there was no difference in the AF/AT free survival (60.0% PVI + CFAE vs 40.0% PVI only, P = .329).Conclusion:Persistent AF ablation targeting CFAE areas within low voltage zones using high-density voltage mapping had a higher AF free survival than a PVI only. Although recurrence with AT was frequent in the PVI+CFAE group, the sinus rhythm maintenance rate after redo procedures was 76%.     

Thoracoscopic radiofrequency ablation for lone atrial fibrillation: Box-lesion technique

BackgroundWe report the feasibility and outcomes of box-lesion ablation technique to treat stand-alone atrial fibrillation (AF).MethodsThere were 31 patients with a mean age of 63.3 ± 8.4 years who underwent bilateral totally thoracoscopic ablation of symptomatic paroxysmal AF (n = 8; 25.8%) and long-standing persistent AF (n = 23; 75.2%). The box-lesion procedure included bilateral pulmonary vein and left atrial posterior wall ablation using irrigated bipolar radiofrequency with documentation of conduction block.ResultsThere were no intra- or perioperative ablation-related complications. There was no operative mortality, no myocardial infarction, and no stroke. Skin-to-skin procedure time was 152.1 ± 36.7 min and the postoperative average length of stay was 6.26 ± 1.24 days. At discharge, 29 patients (93.5%) were in sinus rhythm. Median follow-up time was 20.4 ± 8.3 months. At three months postsurgery, 20 patients of 30 (66.6%) were free from AF without the need of antiarrhythmic drugs. Six patients (20%) underwent catheter reablation. Twenty-three patients (76.6%) were in sinus rhythm at one year after the last performed ablation (surgical ablation or catheter reablation).ConclusionThe thoracoscopic box-lesion ablation procedure is a safe, effective, and minimally invasive method for the treatment of isolated (lone) AF. This procedure provided excellent short-term freedom from AF.     

Assessment of clinical factors associated with a successful catheter ablation outcome in younger patients with atrial fibrillation

BackgroundCatheter ablation is now an alternative approach to antiarrhythmic drug therapy for patients with symptomatic atrial fibrillation (AF). We focused on younger patients in whom the prevalence of AF is low, and we sought clinical factors associated with unsuccessful ablation outcomes.Methods and resultsAmong 1983 consecutive symptomatic patients who underwent AF ablation procedures, 95 patients (4.8%), age ≤ 40 years, were prospectively included. Of them, 64 had paroxysmal AF, and the remaining 31 had persistent AF. All patients underwent pulmonary vein isolation and cavotricuspid isthmus ablation. When AF recurred, redo ablations were performed if the patients desired. The mean number of ablation procedures was 1.3 ± 0.6 times per patient. During the follow-up of 40 [27.8–49.6] months, sinus rhythm was maintained in 86 patients (90.5%) without any antiarrhythmic drugs, but not in the remaining 9 patients (9.5%). Low body mass index (BMI) and persistent AF were associated with unsuccessful ablation procedures. In multivariate logistic regression analysis, a low BMI had the most significant value, with an odds ratio of 7.33 (p = 0.022). The receiver operating characteristic curve demonstrated a BMI cut point of 22.1 kg/m², with an area under the curve of 0.773.ConclusionIn symptomatic younger AF patients, a low BMI was an independent clinical factor for unsuccessful AF ablation outcomes.     

Is radiofrequency energy a necessary and safe complement to cryotherapy for successful pulmonary vein isolation?

IntroductionPulmonary vein (PV) isolation is considered the cornerstone of atrial fibrillation (AF) catheter ablation. PV isolation (PVI) by means of cryotherapy has emerged as a promising technique due to both a low thrombogenicity and reduced risk of PV stenosis. The evaluation (need/efficiency/safety) of hybrid therapy (defined as the use of cryotherapy followed by that of radiofrequency energy in a given patient) is the aim of the present study.MethodsThirty-four consecutive patients (26 men, mean age: 56.7 ± 9.3 years) with symptomatic drug-refractory paroxysmal AF underwent PVI using a balloon-cryotherapy (BCT). A maximum of four cryotherapy applications was applied per PV and disconnection assessed thereafter using a circular LASSO® catheter. When necessary, PV disconnection was then performed using a 4 mm irrigated-tip catheter. All patients underwent CT-scan evaluation before discharge to detect acute PV stenosis.ResultsPVI could be achieved in all patients. Mean procedure duration was 230 ± 42 min and mean fluoroscopy time was 52 ± 13 min. Hybrid therapy was needed to achieve PVI in 26 of 34 (76%). With cryoablation solely, PVI was achieved in 90 of 136 (66%) targeted veins, efficacy being higher in superior as compared to inferior PVs (87% vs. 46%, p < 0.001). Besides one patient with permanent right phrenic nerve injury, no other procedure-related complications were observed. After a mean follow-up period of 8 ± 3 months, 28 patients (82%) did not experience AF recurrence (including six patients on antiarrhythmic drugs).ConclusionsOur study suggests that hybrid ablation therapy is necessary in most patients to achieve PV disconnection after a maximum of four blinded applications of balloon-cryotherapy (especially in inferior PVs), with a significant short-term success rate.     

Use of antiarrhythmic drugs during ablation of persistent atrial fibrillation: observations from a large single-centre cohort

Catheter ablation of complex fractionated atrial electrograms (CFAE), also known as defragmentation ablation, may be considered for the treatment of persistent atrial fibrillation (AF) beyond pulmonary vein isolation (PVI). Concomitant antiarrhythmic drug (AAD) therapy is common, but the relevance of AAD administration and its optimal timing during ablation remain unclear. Therefore, we investigated the use and timing of AADs during defragmentation ablation and their possible implications for AF termination and ablation success in a large cohort of patients. Retrospectively, we included 200 consecutive patients (age: 61 ± 12 years, LA diameter: 47 ± 8 mm) with persistent AF (episode duration 47 ± 72 weeks) who underwent de novo ablation including CFAE ablation. In all patients, PVI was performed prior to CFAE ablation. The use and timing of AADs were registered. The follow-ups consisted of Holter ECGs and clinical visits. Termination of AF was achieved in 132 patients (66 %). Intraprocedural AADs were administered in 168/200 patients (84 %) 45 ± 27 min after completion of PVI. Amiodarone was used in the majority of the patients (160/168). The timing of AAD administration was predicted by the atrial fibrillation cycle length (AFCL). At follow-up, 88 patients (46 %) were free from atrial arrhythmia. Multivariate logistic regression analysis revealed that administration of AAD early after PVI, LA size, duration of AF history, sex and AFCL were predictors of AF termination. The administration of AAD and its timing were not predictive of outcome, and age was the sole independent predictor of AF recurrence. The administration of AAD during ablation was common in this large cohort of persistent AF patients. The choice to administer AAD therapy and the timing of the administration during ablation were influenced by AFCL, and these factors did not significantly influence the moderate single procedure success rate in this retrospective analysis.     

Incidence of asymptomatic cerebral microthromboembolism after atrial fibrillation ablation guided by complex fractionated atrial electrogram

Cerebral Microthromboembolism After CFAE Ablation . Background: The incidence of cerebral thromboembolism after pulmonary vein isolation (PVI) ranges from 2% to 14%. This study investigated the incidence of cerebral thromboembolism after complex fractionated atrial electrogram (CFAE) ablation with or without PVI. Methods: One hundred consecutive atrial fibrillation (AF) patients (50 paroxysmal and 50 persistent, including 10 longstanding) who underwent CFAE ablation combined with (n = 41, PVI+CFAE group) or without (n = 59, CFAE group) PVI were studied. Coronary angiography (CAG) was conducted with AF ablation in 5 cases in which coronary artery stenosis was suspected on 3D‐computed tomography. PVI was performed before CFAE ablation without circular catheter during AF. After termination of AF, additional ablation was performed to complete PVI with a circular catheter. All patients underwent cerebral magnetic resonance imaging (MRI) including diffusion‐weighted MRI and T2‐weighted MRI the day after ablation. Results: New thromboembolism was detected in 7.0%, and there was no significant difference between the 2 strategies (7.3% in PVI+CFAE group, 6.8% in CFAE group). CHADS2 score (1.6 ± 1.0 vs 0.8 ± 0.9, P < 0.05), left atrial volume (LAV; 83.8 ± 27.1 vs 67.8 ± 21.8, P < 0.05), and left ventricular ejection fraction (LVEF, 53.1 ± 9.2 vs 65.1 ± 9.7, P < 0.01) were significantly different when comparing patients with or without thromboembolism. In multivariate analysis, LVEF (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.84–0.99; P < 0.05) and concomitant CAG (OR 18.82; 95% CI, 1.77–200.00; P < 0.05) were important predictors of new cerebral thromboembolism. Conclusions: The incidence of cerebral microthromboembolism after CFAE ablation was not greater than previous reports in PVI. Cautious management is required during AF ablation, especially in the patients with low LVEF. (J Cardiovasc Electrophysiol, Vol. 23, pp. 567–573, June 2012)     

Additional complex fractionated atrial electrogram ablation does not improve the outcomes of non-paroxysmal atrial fibrillation: A systematic review and meta-analysis of randomized controlled trials

BackgroundNon-paroxysmal atrial fibrillation (AF) has a complex pathophysiological process. The standard catheter ablation approach is pulmonary vein isolation (PVI). The additional value of complex fractionated electrogram (CFAE) ablation is still unclear. We aimed to investigate the additional value of CFAE ablation for non-paroxysmal AF.MethodsWe performed a systematic review and meta-analysis of randomized controlled studies up to May 2020. Articles comparing pulmonary vein isolation (PVI) plus CFAE ablation and PVI alone for AF were obtained from the electronic scientific databases. The pooled mean difference (MD) and pooled risk ratio (RR) were assessed.ResultsA total of 8 randomized controlled trials (RCTs) including 1034 patients were involved. Following a single catheter ablation procedure, the presence of any atrial tachyarrhythmia (ATA) with or without the use of antiarrhythmic drugs (AADs) between both groups were not significantly different (RR = 1.1; 95% confidence interval [CI] = 0.97–1.24; p = 0.13). Similar results were also obtained for the presence of any ATA without the use of AADs (RR = 1.08; 95% CI = 0.96–1.22; p = 0.2). The additional CFAE ablation took longer procedure times (MD = 46.95 min; 95% CI = 38.27–55.63; p = < 0.01) and fluoroscopy times (MD = 11.69 min; 95% CI = 8.54–14.83; p = < 0.01).ConclusionAdditional CFAE ablation failed to improve the outcomes of non-paroxysmal AF patients. It also requires a longer duration of procedure times and fluoroscopy times.     

Increased level of resistin predicts development of atrial fibrillation

BackgroundResistin is a peptide hormone that is secreted from lipid cells and is linked to type-2 diabetes, obesity, and inflammation. Being an important adipocytokine, resistin was proven to play an important role in cardiovascular disease. We compared resistin levels in patients with and without atrial fibrillation (AF) to demonstrate the relationship between plasma resistin levels and AF.MethodOne hundred patients with AF and 58 control patients who were matched in terms of age, gender, and risk factors were included in the trial. Their clinical risk factors, biometric measurements, echocardiographic work up, biochemical parameters including resistin and high-sensitivity C-reactive protein (hs-CRP) levels were compared.ResultsIn patients with AF, plasma resistin levels (7.34 ± 1.63 ng/mL vs 6.67 ± 1.14 ng/mL; p = 0.003) and hs-CRP levels (3.01 ± 1.54 mg/L vs 2.16 ± 1.28 mg/L; p = 0.001) were higher than control group. In subgroup analysis, resistin levels were significantly higher in patients with paroxysmal (7.59 ± 1.57 ng/mL; p = 0.032) and persistent AF (7.73 ± 1.60 ng/mL; p = 0.006), but not in patients with permanent AF subgroups (6.86 ± 1.61 ng/mL; p = 0.92) compared to controls. However, hs-CRP levels were significantly higher only in permanent AF patients compared to control group (3.26 ± 1.46 mg/L vs 2.16 ± 1.28 mg/L; p = 0.02). In multivariate regression analysis using model adjusted for age, gender, body mas index, hypertension, diabetes mellitus, and creatinine levels, plasma resistin levels [odds ratio (OR): 1.30; 95% confidence interval (CI): 1.01–1.70; p = 0.04] and hs-CRP levels (OR: 1.44; 95% CI: 1.12–1.86; p = 0.004) were the only independent predictors of AF.ConclusionThe elevated levels of plasma resistin were related to paroxysmal AF group and persistent AF group, but not to permanent AF group.     

Poor relationship between left atrial diameter and volume in patients with atrial fibrillation

BackgroundLeft atrial (LA) enlargement is a predictor of worse outcome after catheter ablation for atrial fibrillation (AF). We investigated the correspondence between single LA diameter (LAd) and LA volume (LAV) in patients undergoing catheter ablation for AF.MethodsTotal 782 patients (aged 58±11 yrs; 70% males; 56% paroxysmal AF) were enroled in 2 centres in the period of 2007–2011. Echocardiographic antero-posterior LAd was assessed in parasternal long-axis view and LAV was derived from electroanatomic 3 D reconstruction of LA (183±50 CARTO mapping points; 55% CT image registration).ResultsMean LAd was 45±6 mm (median: 45; IQR: 41–49; range: 25–73 mm) and mean LAV was 134±42 ml (median: 128; IQR: 103–160; range: 46–313 ml). Correlation between both variables was weak (r=0.56; p <0.0001) and area under the ROC curve for the LAd-based prediction of LAV >130 was 0.76. Accordingly, severe dilation of LA (LAV >160 ml; upper quartile) was found only in 56% of patients with LAd >50 mm while it appeared in 11% of those with LAd<45 mm. In multivariate regression analysis, age, gender, and type of AF were independent covariates of LAV yielding the equation of LAV (ml)=68+0.41.cube LAd (cc)+15 (if male)+0.48.age (yrs) – 21 (if paroxysmal AF). Substantial between-centre bias was also found reflecting subjective nature of echocardiographic readings. Adjustment for all covariates improved the correspondence between LAd-predicted and true LAV only modestly (AUC increased from 0.76 to 0.83) with wide 95% limits of agreement (?58 to +60 ml).ConclusionsConsiderable disagreement between echocardiographic LAd and 3D mapping LAV was observed in patients with non-valvular atrial fibrillation. Single LA dimension should not be considered relevant criterion for the indication of rhythm/rate control therapy and, particularly, for the selection of suitable candidates for catheter ablation.     

Prediction of atrial fibrillation after ischemic stroke using P-wave signal averaged electrocardiography

BackgroundAtrial fibrillation (AF) is highly prevalent in patients with ischemic stroke, but the diagnosis is often difficult.MethodsThis study consisted of 68 stroke patients in sinus rhythm without history of AF. All patients underwent P-wave signal-averaged electrocardiography (P-SAECG), echocardiography, 24-h Holter monitoring, and measurement of plasma B-type natriuretic peptide (BNP) concentrations at admission.ResultsAn abnormal P-SAECG was found in 34 of 68 stroke patients. In the follow-up period of 11 ± 4 months, AF developed in 17 patients (AF group). The remaining 51 patients were classified as the non-AF group. The prevalence of atrial late potentials (ALP) on P-SAECG, and the number of premature atrial contractions (PACs) were significantly higher in the AF group than those in the non-AF group (88.2% vs 37.3%; p < 0.001, 149 ± 120 vs 79 ± 69; p = 0.030, respectively). However, there were no significant differences in age, left atrial dimension, or BNP concentrations between both groups. Cox proportional hazards analysis revealed that the presence of ALP (risk ratio 11.15; p = 0.002) and frequent PACs (more than 100/24 h) (risk ratio 4.53; p = 0.007) had significant correlation to the occurrence of AF.ConclusionsALP may be a novel predictor of AF in stroke patients. P-SAECG should be considered in stroke of undetermined etiology.     

Incidence and Significance of Early Recurrences Associated with Different Ablation Strategies for AF: A STAR‐AF Substudy

Early Recurrence in STAR‐AF. Background: Early recurrences of atrial tachyarrhythmias (ERAT) are common after atrial fibrillation (AF) ablation, and predict late recurrences (LR). We sought to determine the impact of different ablation strategies on ERAT and LR. Methods and Results: The STAR‐AF trial randomized 100  patients with paroxysmal or persistent AF to ablation of complex fractionated electrograms (CFAE) alone, pulmonary vein isolation (PVI) alone, or combined PVI + CFAE. Patients were followed for 12  months. ERAT was defined as any recurrence of AF, atrial tachycardia, or flutter (AT/AFL) >30 seconds during the first 3  months of follow‐up. LR was defined as any recurrence of AF/AT/AFL >30 seconds 3–12  months post. Forty‐nine patients experienced ERAT. The index ablation strategy was the only independent predictor of ERAT on multivariate analysis (HR 2.24 PVI vs PVI + CFAE; and HR 2.65 CFAE vs PVI + CFAE). Fifty‐two patients experienced LR. The presence of ERAT (HR 3.23), the use of antiarrhythmic drug (AAD) in the first 3  months postablation (HR 2.85), and the index ablation strategy were independently associated with LR (HR 3.42 PVI vs PVI + CFAE; HR 4.72 CFAE vs PVI + CFAE). Thirty‐five of 49 (71%) patients with ERAT and 17 (33%) of 51  patients without ERAT had LR (P  < 0.0001). Among patients with ERAT, increased left atrium size (HR 1.08), the use of AAD in the first 3  months postablation (HR 2.86) and the index ablation strategy were independently associated with LR (HR 4.77 PVI vs PVI + CFAE; HR 4.45 CFAE vs PVI + CFAE). Conclusion: ERAT is common following AF ablation and is strongly associated with LR. Although CFAE ablation alone results in higher rates of early and LR, the addition of CFAE to PVI results in increased long‐term success without an increase in ERAT. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1295‐1301, December 2012)     

El fracaso de la ablación por catéter de la fibrilación auricular se asocia con mayor remodelado y menos eficacia de una posterior ablación toracoscópica

Introduction and objectivesRecent observations suggest that patients with a previous failed catheter ablation have an increased risk of atrial fibrillation (AF) recurrence after subsequent thoracoscopic AF ablation. We assessed the risk of AF recurrence in patients with a previous failed catheter ablation undergoing thoracoscopic ablation.MethodsWe included patients from 3 medical centers. To correct for potential heterogeneity, we performed propensity matching to compare AF freedom (freedom from any atrial tachyarrhythmia > 30 s during 1-year follow-up). Left atrial appendage tissue was analyzed for collagen distribution.ResultsA total of 705 patients were included, and 183 had a previous failed catheter ablation. These patients had fewer risk factors for AF recurrence than ablation naïve controls: smaller indexed left atrial volume (40.9 ± 12.5 vs 43.0 ± 12.5 mL/m², P = .048), less congestive heart failure (1.5% vs 8.9%, P = .001), and less persistent AF (52.2% vs 60.3%, P = .067). However, AF history duration was longer in patients with a previous failed catheter ablation (6.5 [4-10.5] vs 4 [2-8] years; P < .001). In propensity matched analysis, patients with a failed catheter ablation were at a 68% higher AF recurrence risk (OR, 1.68; 95%CI, 1.20-2.15; P = .034). AF freedom was 61.1% in patients with a previous failed catheter ablation vs 72.5% in ablation naïve matched controls. On histology of the left atrial appendage (n = 198), patients with a failed catheter ablation had a higher density of collagen fibers.ConclusionsPatients with a prior failed catheter ablation had fewer risk factors for AF recurrence but more frequently had AF recurrence after thoracoscopic AF ablation than ablation naïve patients. This may in part be explained by more progressed, subclinical, atrial fibrosis formation.     

Impact of catheter ablation on P-wave parameters on 12-lead electrocardiogram in patients with atrial fibrillation

BackgroundCatheter ablation has emerged as a widely used treatment modality for atrial fibrillation (AF). P-wave abnormalities have been described in the patients with AF, and catheter ablation may potentially further impact P-wave parameters due to ablation of atrial tissue.MethodsWe reviewed data on P-wave parameters (P-wave duration, amplitude and P-wave duration and amplitude product) in leads V1 and aVF and changes in the P-terminal force (Ptf; product of duration and amplitude of terminal part of P-wave) in lead V1 from 12-lead electrocardiograms obtained prior to and after CA of a total of 46 (28 paroxysmal and 18 persistent) AF patients.ResultsThe median age of patients in our study was 63 (range: 30–77) years. We noticed a significant reduction in the P-wave duration (from 87.39 ± 28.62 ms at baseline to 72.09 ± 24.59 ms; p = 0.0072) and the product of P-wave duration and amplitude in lead V1 (12.16 ± 5.54 mV ms at baseline to 8.30 ± 5.78 mV ms, p = 0.0015) after CA. There was also a significant decrease in P-wave duration (from 92.57 ± 19.67 ms at baseline to 76.48 ± 16.32 ms after CA, p = 0.0001) and P-wave duration and amplitude product in lead aVF (12.61 ± 4.05 mV ms at baseline to 9.77 ± 3.86 m V ms after CA, p = 0.0001). CA also led to a significant decrease in Ptf (from 4.56 ± 1.88 at baseline to 2.85 ± 1.42 mV ms, p < 0.0001).ConclusionRadiofrequency catheter ablation of AF leads to modification of P-wave parameters with substantial diminution in both the amplitude and duration of the P-wave in leads V1 and aVF. This likely represents reduction in electrically active atrial tissue after ablation, and may serve as a marker for the extent of ablated atrial tissue.     

Women with atrial fibrillation and type 2 diabetes have a higher incidence of hospitalization and undergo ablation or pacemaker implantation less frequently than men

BackgroundWe reviewed trends from 2004 to 2013 in the incidence and outcomes for atrial fibrillation (AF) in Spanish patients with type 2 diabetes mellitus (T2DM) comparing women and men.MethodsWe used national hospital discharge data including all T2DM patients discharged from the hospital after AF. Patients with AF in the primary diagnosis field were selected. Discharges were grouped by sex. Incidence was calculated overall and stratified by sex. We analyzed diagnostic and therapeutic procedures, patient comorbidities, CHA2DS2-VASc score, length of hospital stay, readmission rates and in-hospital mortality (IHM).ResultsWe identified a total of 214,457 admissions for AF. Patients with T2DM accounted for 21.1% (19,505 men and 25,954 women). Women with T2DM had a significantly higher incidence of AF compared to men over the study period (IRR 1.33;95%CI 1.31–1.35). Women were significantly older (77.24 ± 8.69 years) than men (72.62 ± 10.28 years), had higher prevalences of obesity and hypertension, and higher CHA2DS2-VASc score. Women less frequently underwent ablation (3.21% vs. 1.54%; p < 0.001) and received an implanted pacemaker (14.3% vs. 8.16%; p < 0.001) than men. Crude IHM was 2.81% for women and 2.48% for men (p = 0.030). Sex was not associated with a higher IHM after multivariable adjustment.ConclusionsOur study demonstrates an increase in hospitalization for AF in diabetic women. Women were older, had a higher comorbidity index and had CHAD2DS2-VASc score than men. Women with AF and T2DM undergo ablation or pacemaker implantation less frequently than their male counterparts. After multivariable adjustment sex did not predict mortality during admissions for AF.     

The role of flow-mediated dilatation and high sensitive C-reactive protein in paroxysmal atrial fibrillation

BackgroundAtrial fibrillation (AF) is the most common type of arrhythmia and recognized as a risk factor for thromboembolism. Endothelial damage or dysfunction may contribute to increase the risk of thromboembolism via the mediation of a prothrombotic or hypercoagulable state.ObjectivesThe aim of the current study is to investigate endothelial dysfunction (represented by brachial flow-mediated dilatation “FMD”) and inflammation (represented by hs-CRP) in patients with paroxysmal atrial fibrillation.Subjects and methodsForty-two patients with AF taken from the Cardiology Department and Outpatients Clinic, Specialized Medical Hospital, Mansoura University, in the period between February 2011 and May 2011 were enrolled in our study, the patients were then subsequently divided according to the clinical type of AF into Group I: comprised 20 patients with paroxysmal AF (PAF) with mean age 57.35y. Group II: comprised 22 patients with chronic AF (CAF) with mean age 57.68y. Twenty control subjects without AF were enrolled in this study (Group III). Patients and control groups were subjected to clinical evaluation, electrocardiography (ECG), echocardiography and brachial FMD (using external brachial ultrasonography. Serum level of hs-CRP was assessed in all subjects. The diameter change induced by FMD was expressed as the percent change relative to that at the initial scan (FMD%) according to the following equation:$\text{FMD}\%=\frac{\text{Maximum diameter}-\text{baseline diameter}}{\text{Baseline diameter}}\times 100\text{.}$ResultsLeft atrial diameter was significantly increased when compared either GI or GII with control group (3.96 ± 0.27; 4.7 ± 0.48 vs 3.05 ± 0.35 cm) (P < 0.001). Brachial flow-mediated dilatation difference and percentage change of FMD were significantly lower in groups I and II in comparison to group III (0.09 ± 0.05; 0.09 ± 0.04 vs 0.79 ± 0.07 mm) and (1.96 ± 0.98; 1.99 ± 0.89 vs 18.3 ± 3.26) (P < 0.001). High sensitive CRP was significantly higher when compared either group I or group II with control group. Also hs-CRP has significantly increased when compared GII with group I (8.35 ± 1.55; 10.58 ± 1.75 vs 3.61 ± 0.61 mg/L) (P < 0.001).ConclusionPatients with PAF are comparable in the degree of endothelial dysfunction (reflected as impaired brachial artery FMD) and inflammatory element (reflected as a higher serum hs-CRP) to CAF. This may explain why the risk of thromboembolism in PAF is comparable with that in CAF patients.     

MMP-9 in atrial remodeling in patients with atrial fibrillation

IntroductionAtrial fibrillation (AF) is the most common arrhythmia and is associated with significant morbidity and mortality. The impact of matrix metalloproteinases (MMPs) on structural atrial remodeling and sustainment of AF in patients with persistent and permanent AF is unresolved.ObjectivesThe aim was to evaluate MMP-9 and its tissue inhibitor-1 (TIMP-1) as markers of atrial remodeling in patients with persistent AF (PAF) who underwent electrical cardioversion (ECV) and in patients with permanent AF (continuous AF, CAF).Patients and methodsPlasma levels of MMP-9 and TIMP-1, clinical findings, and echocardiographic parameters were evaluated in 39 patients with AF and in 14 controls with sinus rhythm.ResultsThe concentrations of MMP-9 were significantly higher in patients with PAF and CAF compared to controls. There was a significant increase of MMP-9 after ECV in the persistent AF group. The values of TIMP-1 were not significantly different between the groups. In patients with AF, MMP-9 levels were positively related to posterior wall thickness of the LV (r = 0.356, P = 0.049) and body mass index (r = 0.367, P = 0.046).ConclusionElevated levels of MMP-9 were related to the occurrence and maintenance of AF. This suggests that MMP-9 can be a marker of atrial remodeling in patients with AF. Regulation of the extracellular collagen matrix might be a potential therapeutic target in AF.     

Prediction of atrial fibrillation via atrial electromechanical interval after coronary artery bypass grafting

Objectives: We sought to analyze the value of measuring atrial electromechanical interval (AEMI) in predicting post coronary artery bypass grafting (CABG) atrial fibrillation (AF).Background: Atrial fibrillation is the most common arrhythmia after CABG with as many as 10–40%. Several predictors are associated with the development of AF after cardiac surgery.Methods: At least 30 patients; 18 males and 12 females (mean age 53 + 12 years) with ischemic heart disease diagnosed by coronary angiography and underwent CABG enrolled in the study. Pre-operative data were collected including laboratory, 12-lead ECG to measure P wave duration and P wave dispersion, trans-thoracic echocardiography to measure LV dimensions, ejection fraction, and LA volume. Pre-operative tissue Doppler imaging (TDI) was used to measure atrial electromechanical interval (AEMI) in milliseconds from the onset of P wave on the surface electrogram till the onset of atrial systole (Am).Results: Our patients were classified into two groups, group I with documented post CABG AF and group II with no AF. It was found that the mean value of AEMI in group I patients was significantly longer; 136 + 5.6 vs 93.7 + 19 ms in group II patients (P < 0.001). Using receiver operator characteristic (ROC) analysis, it was found that the cutoff value of AEMI as a predictor of post CABG AF was 120 ms which achieves 100% sensitivity and 99% specificity. It was found also significantly increased P wave duration and dispersion in group I patients compared to group II (97.7 ± 3 vs 94 ± 3.9 ms; P = 0.02 and 26 ± 4.7 vs 23 ± 4.7; P = 0.04, respectively).Conclusion: using AEMI as a predictor of post CABG AF is a valuable marker which carries high sensitivity and specificity.     

Efficacy of cardiac autonomic denervation for atrial fibrillation: a meta-analysis

Cardiac Autonomic Denervation and AF. Introduction : Adjunctive complex fractionated atrial electrograms (CFAE) ablation or ganglionated plexi (GP) ablation have been proposed as new strategies to increase the elimination of AF, but the difference between CFAE/GP ablation and pulmonary vein isolation (PVI), as well as the combined effect of CFAE/GP plus PVI ablation were unclear. This meta‐analysis was designed to determine whether adjunctive cardiac autonomic denervation (CAD) was effective for the elimination of AF, and whether CAD alone was superior to PVI in AF patients. Methods: A systemic literature search in MEDLINE, EMBASE, and Cochrane Controlled Trials Register (CCRT) was performed and controlled trials comparing the effect of PVI plus CFAE/GP ablation with PVI, as well as CFAE/GP ablation with PVI were collected. Results : A total of 15 trials including 1,147 patients with AF were qualified for this meta‐analysis. CAD plus PVI significantly increased the freedom from AF/ATs (OR 1.85, 95% CI: 1.33–2.59, P = 0.29). Subgroup analysis showed that additional CAD increased the ratio of sinus rhythm maintenance in both paroxysmal AF (OR 1.69; 95% CI: 1.09–2.62, P = 0.41) and nonparoxysmal AF (OR 2.11, 95% CI: 1.14–3.90, P = 0.14). Besides, when compared respectively, adjunctive CAD was not superior to PVI (OR 0.31; 95% CI: 0.11–0.86, P = 0.002). Conclusion : This study suggested that CAD plus PVI significantly increase the freedom from recurrence of AF both in paroxysmal and nonparoxysmal patients. However, when compared alone, the benefit of CAD was not superior to PVI. (J Cardiovasc Electrophysiol, Vol. 23, pp. 592–600, June 2012)     

Selective CFAE targeting for atrial fibrillation study (SELECT AF): clinical rationale, design, and implementation

SELECT AF Methodology & Rationale. Background: Adjuvant ablation of complex fractionated atrial electrograms (CFAE) in addition to pulmonary vein isolation (PVI) likely improves procedural outcome compared to PVI alone, particularly in patients with persistent atrial fibrillation (AF). However, CFAE regions can be extensive, occasionally requiring a large amount of extra ablation. Some CFAE regions may also represent passive wavefront collision and may not require ablation. Thus, there is interest in identifying more selective CFAE sites that are critical to AF perpetuation, minimizing the amount of adjuvant ablation that must be performed. Objective: The SELECT AF study is a prospective, multicenter, randomized trial comparing a strategy of PVI plus generalized CFAE ablation versus a strategy of PVI plus selective CFAE ablation, focusing on regions of continuous electrical activity (CEA). The primary efficacy endpoint is freedom from atrial arrhythmia at 1 year and the primary safety endpoint is total radiofrequency (RF) delivery time per procedure. Methods: Patients undergoing a first time ablation procedure for symptomatic persistent AF will be included. Patients with permanent AF or with left atrial size ≥55 mm will be excluded. Patients will all receive PVI at the time of their ablation, but will be randomized 1:1 to receive adjuvant CFAE ablation using the traditional “generalized” approach, or a “selective” approach targeting only CEA regions. Both strategies will be guided by automated mapping algorithms. This study will enroll a minimum of 80 evaluable subjects; 40 in each randomization group. Conclusions: SELECT AF is a randomized trial in patients with persistent AF to evaluate the efficacy of selective versus generalized CFAE ablation in addition to traditional PVI. (J Cardiovasc Electrophysiol, Vol. 22, pp. 541‐547 May 2011)