Vein Isolation For Atrial Fibrillation Research Articles

Randomized comparison of contact force-guided versus conventional circumferential pulmonary vein isolation of atrial fibrillation: prevalence, characteristics, and predictors of electrical reconnections and clinical outcomes.

We prospectively investigated the differences in pulmonary vein reconnections (PVRs) and clinical outcomes between contact force (CF)-guided and conventional circumferential PV isolation (CPVI) of atrial fibrillation (AF). One hundred twenty consecutive AF patients (63 ± 10 years; 88 males) undergoing an initial CPVI were randomized to ablation with a target CF of 20 g (CF group; n = 60) or that with operators blinded to the CF information (blind group; n = 60). The CF group had fewer PVRs (0.67 ± 0.91/patient vs. 1.16 ± 1.16/patient; P = 0.007), a lower incidence of persistent PVRs (13.2 vs. 41.2%; P < 0.001), and a shorter procedural time for the CPVI (50 vs. 56 min; P = 0.019) than the blind group. The mean CF was higher in the CF group than the blind group (18.0 vs. 16.1 g; P < 0.001), with the most significant difference observed along the posterior right-sided PVs (P-RPVs) and anterior left-sided PVs (A-LPVs). In logistic regression models, the mean CF was a negative predictor of PVRs along the P-RPVs and A-LPVs in the blind group (odds ratios, 0.728 and 0.786; P < 0.001 and 0.007), while no significant predictor was identified in the CF group or elsewhere in the blind group. In the Kaplan-Meier analysis, the arrhythmia-free survival rate at 12 months was 89.9% in the CF group and 88.2% in the blind group, respectively (P = 0.624). CF-guided CPVI can reduce PVRs and the procedural time and be particularly beneficial along regions where a relatively low CF tends to be applied: the P-RPVs and A-LPVs. The comparable clinical outcomes may be due to the learning curve effect obtained by the CF-guided technique and repeated provocation of dormant PV conduction.

Adenosine triphosphate-guided pulmonary vein isolation for atrial fibrillation: the UNmasking Dormant Electrical Reconduction by Adenosine TriPhosphate (UNDER-ATP) trial.

Most of recurrent atrial tachyarrhythmias after pulmonary vein isolation (PVI) for atrial fibrillation (AF) are due to reconnection of PVs. The aim of the present study was to evaluate whether elimination of adenosine triphosphate (ATP)-induced dormant PV conduction by additional energy applications during the first ablation procedure could reduce the incidence of recurrent atrial tachyarrhythmias. We randomly assigned 2113 patients with paroxysmal, persistent, or long-lasting AF to either ATP-guided PVI (1112 patients) or conventional PVI (1001 patients). The primary endpoint was recurrent atrial tachyarrhythmias lasting for >30 s or those requiring repeat ablation, hospital admission, or usage of Vaughan Williams class I or III antiarrhythmic drugs at 1 year with the blanking period of 90 days post ablation. Among patients assigned to ATP-guided PVI, 0.4 mg/kg body weight of ATP provoked dormant PV conduction in 307 patients (27.6%). Additional radiofrequency energy applications successfully eliminated dormant conduction in 302 patients (98.4%). At 1 year, 68.7% of patients in the ATP-guided PVI group and 67.1% of patients in the conventional PVI group were free from the primary endpoint, with no significant difference (adjusted hazard ratio [HR] 0.89; 95% confidence interval [CI] 0.74-1.09; P = 0.25). The results were consistent across all the prespecified subgroups. Also, there was no significant difference in the 1-year event-free rates from repeat ablation for any atrial tachyarrhythmia between the groups (adjusted HR 0.83; 95% CI 0.65-1.08; P = 0.16). In the catheter ablation for AF, we found no significant reduction in the 1-year incidence of recurrent atrial tachyarrhythmias by ATP-guided PVI compared with conventional PVI.

Effects of Atorvastatin (80 mg) Therapy on Quantity of Epicardial Adipose Tissue in Patients Undergoing Pulmonary Vein Isolation for Atrial Fibrillation

Epicardial adipose tissue (EAT) has been recognized as a sensitive marker of cardiometabolic risk. Recent evidence suggests efficacy of long-term statin therapy in reducing EAT in patients with coronary artery disease. Whether short-term statin therapy is associated with changes in the volume of EAT is currently unknown. A cohort of patients with atrial fibrillation who underwent pulmonary vein isolation were randomized to receive either 80mg/day of atorvastatin (n= 38, 32 men, age 56 ± 11years) or placebo (n= 41, 33 men, age 56 ± 10years) for a 3-month period. EAT volume was assessed by cardiac computed tomography at baseline and at follow-up. Patients randomized to statin treatment exhibited a modest but significant decrease in median EAT volume (baseline vs follow-up: 92.3 cm(3) [62.0 to 133.3] vs 86.9 cm(3) [64.1 to 124.8], p <0.05), whereas median EAT remained unchanged in the placebo group (81.9 cm(3) [55.5 to 110.9] vs 81.3 cm(3) [57.1to 110.5], p= NS). Changes in median systemic inflammatory markers and lipid profile were also seen with statin treatment: C-reactive protein (2.4 mg/L [0.7 to 3.7] vs 1.1 mg/L [0.5 to 2.7], p <0.05), total cholesterol (186 mg/dL [162.5 to 201] vs 123 mg/dL [99 to 162.5], p <0.001), and low-density lipoprotein cholesterol (116 mg/dL [96.5 to 132.5] vs 56 [40.5 to 81] mg/dL, p <0.001) diminished, whereas median body mass index did not change (27.8kg/m(2) [25 to 30] versus 27.6 kg/m(2) [25.7 to 30.5], p= NS). No variations occurred in the placebo group. In conclusion, short-term intensive statin therapy significantly reduced the volume of EAT in patients with atrial fibrillation.

Anesthetic management in atrial fibrillation ablation procedure: Adding non-invasive ventilation to deep sedation

Anesthetic management of patients undergoing pulmonary vein isolation for atrial fibrillation has specific requirements. The feasibility of non-invasive ventilation (NIV) added to deep sedation procedure was evaluated.Seventy-two patients who underwent ablation procedure were retrospectively revised, performed with (57%) or without (43%) application of NIV (Respironic® latex-free total face mask connected to Garbin ventilator-Linde Inc.) during deep sedation (Midazolam 0.01–0.02 mg/kg, fentanyl 2.5–5 μg/kg and propofol: bolus dose 1–1.5 mg/kg, maintenance 2–4 mg/kg/h).In the two groups (NIV vs deep sedation), differences were detected in intraprocedural (pH 7.37 ± 0.05 vs 7.32 ± 0.05, p = 0.001; PaO2 117.10 ± 27.25 vs 148.17 ± 45.29, p = 0.004; PaCO2 43.37 ± 6.91 vs 49.33 ± 7.34, p = 0.002) and in percentage variation with respect to basal values (pH −0.52 ± 0.83 vs −1.44 ± 0.87, p = 0.002; PaCO2 7.21 ± 15.55 vs 34.91 ± 25.76, p = 0.001) of arterial blood gas parameters. Two episodes of respiratory complications, treated with application of NIV, were reported in deep sedation procedure. Endotracheal intubation was not necessary in any case. Adverse events related to electrophysiological procedures and recurrence of atrial fibrillation were recorded, respectively, in 36% and 29% of cases.NIV proved to be feasible in this context and maintained better respiratory homeostasis and better arterial blood gas balance when added to deep sedation.

OP-108 Impact of Left Atrial Diverticula on Outcome Following Cryoballoon-based Pulmonary Vein Isolation for Atrial Fibrillation

OP-108 Impact of Left Atrial Diverticula on Outcome Following Cryoballoon-based Pulmonary Vein Isolation for Atrial Fibrillation

OP-122 Renal Function Reflected with Serum Beta-trace Protein Level is an Independent Predictor of Outcome Following Cryoballoon-based Pulmonary Vein Isolation for Atrial Fibrillation

OP-122 Renal Function Reflected with Serum Beta-trace Protein Level is an Independent Predictor of Outcome Following Cryoballoon-based Pulmonary Vein Isolation for Atrial Fibrillation

Pulmonary vein isolation for atrial fibrillation in the postpneumonectomy population: a feasibility, safety, and outcomes study.

Pulmonary vein isolation (PVI) of the remnant pulmonary vein (PV) stumps in pneumonectomy patients has not been well characterized. This is a multicenter observational study of patients with a remnant PV stump after pneumonectomy. Consecutive patients with a history of pneumonectomy and who had undergone RF ablation for drug refractory AF were identified from the AF database at the participating institutions. There were 15 patients in whom pneumonectomy was performed, for resection of tumors in 10, infection in 4, and bullae in 1 patient and who underwent RF ablation for AF. The mean age was 63 ± 7 years. The stumps were from the right lower PV in 5, left upper PV in 5, left lower PV in 3, and right upper PV in 2 patients. All the PV stumps were electrically active with PV potentials and 9 (60%) of them had triggered activity. PVI was performed in 14 and focal isolation in 1 patient. At 1-year follow-up, 80% were free of AF, off of antiarrhythmic medications. PV stumps in AF patients with previous pneumonectomy are electrically active and are frequently the sites of active firing. Isolation of these PV stumps can be accomplished safely and effectively using catheter ablation with no practical concern for PV stenosis or compromising PV stump integrity.

Atrial fibrosis and conduction slowing in the left atrial appendage of patients undergoing thoracoscopic surgical pulmonary vein isolation for atrial fibrillation.

Atrial fibrosis is an important component of the arrhythmogenic substrate in patients with atrial fibrillation (AF). We studied the effect of interstitial fibrosis on conduction velocity (CV) in the left atrial appendage of patients with AF. Thirty-five left atrial appendages were obtained during AF surgery. Preparations were superfused and stimulated at 100 beats per minute. Activation was recorded with optical mapping. Longitudinal CV (CVL), transverse CV (CVT), and activation times (> 2 mm distance) were measured. Interstitial collagen was quantified and graded qualitatively. The presence of fibroblasts and myofibroblasts was assessed immunohistochemically. Mean CVL was 0.55 ± 0.22 m/s, mean CVT was 0.25 ± 0.15 m/s, and the mean activation time was 9.31 ± 5.45 ms. The amount of fibrosis was unrelated to CV or patient characteristics. CVL was higher in left atrial appendages with thick compared with thin interstitial collagen strands (0.77 ± 0.22 versus 0.48 ± 0.19 m/s; P = 0.012), which were more frequently present in persistent patients with AF. CVT was not significantly different (P = 0.47), but activation time was 14.93 ± 4.12 versus 7.95 ± 4.12 ms in patients with thick versus thin interstitial collagen strands, respectively (P = 0.004). Fibroblasts were abundantly present and were associated with the presence of thick interstitial collagen strands (P = 0.008). Myofibroblasts were not detected in the left atrial appendage. In patients with AF, thick interstitial collagen strands are associated with higher CVL and increased activation time. Our observations demonstrate that the severity and structure of local interstitial fibrosis is associated with atrial conduction abnormalities, presenting an arrhythmogenic substrate for atrial re-entry.

Gastroesophageal reflux disease is a predictor of atrial fibrillation recurrence following left atrial ablation

Gastroesophageal reflux disease (GERD) is the most common gastrointestinal diagnosis made during visits to outpatient clinics [ 1 Huang C.C. Chan W.L. Luo J.C. Chen Y.C. Chen T.J. Chung C.M. et al. Gastroesophageal reflux disease and atrial fibrillation: a nationwide population-based study. PLoS One. 2012; 7: e47575 Crossref PubMed Scopus (31) Google Scholar , 2 Velagapudi P. Turagam M.K. Leal M.A. Kocheril A.G. Atrial fibrillation and acid reflux disease. Clin. Cardiol. 2012; 35: 180-186 Crossref PubMed Scopus (20) Google Scholar ]. A potential association between GERD and atrial fibrillation (AF) development has been proposed in previous studies, mainly attributed to the close positioning of the esophagus and the left atrium [ 1 Huang C.C. Chan W.L. Luo J.C. Chen Y.C. Chen T.J. Chung C.M. et al. Gastroesophageal reflux disease and atrial fibrillation: a nationwide population-based study. PLoS One. 2012; 7: e47575 Crossref PubMed Scopus (31) Google Scholar , 2 Velagapudi P. Turagam M.K. Leal M.A. Kocheril A.G. Atrial fibrillation and acid reflux disease. Clin. Cardiol. 2012; 35: 180-186 Crossref PubMed Scopus (20) Google Scholar ]. Previous studies have demonstrated a high incidence of pathologic reflux following left atrial (LA) ablation [ 3 Nölker G. Ritscher G. Gutleben K.J. Marschang H. Schmidt M. Rittger H. et al. Esophageal acid levels after pulmonary vein isolation for atrial fibrillation. Pacing Clin. Electrophysiol. 2009; 32: 228-230 Crossref PubMed Scopus (17) Google Scholar , 4 Martinek M. Hassanein S. Bencsik G. Aichinger J. Schoefl R. Bachl A. et al. Acute development of gastroesophageal reflux after radiofrequency catheter ablation of atrial fibrillation. Heart Rhythm. 2009; 6: 1457-1462 Abstract Full Text Full Text PDF PubMed Scopus (45) Google Scholar ]. Data regarding the prognostic significance of GERD on LA ablation outcomes are missing. This study aimed to investigate whether GERD has an impact on AF recurrence after a single LA ablation procedure for paroxysmal AF.

Safety and satisfaction of day case pulmonary vein isolation for atrial fibrillation

Safety and satisfaction of day case pulmonary vein isolation for atrial fibrillation

Abstract 18667: Impact of Direct Contact Force Measurement on Electrical Reconnections after Circumferential Pulmonary Vein Isolation for Atrial Fibrillation Using a Contact Force-Sensing Catheter

Purpose: To prospectively evaluate the incidence of pulmonary vein (PV) reconnections (PVRs) and identify predictors of PVRs after circumferential PV isolation (CPVI) using a contact force (CF)-sensing ablation catheter. Methods: Sixty-five patients (51-males; 61±10 years) undergoing an initial CPVI were studied. Both the right and left CPVI lines were divided into 12 segments and multiple regression models were used to predict PVRs in the four regions (each including 6 segments), the anterior and posterior RPVs and LPVs (A-RPVs, P-RPVs, A-LPVs, and P-LPVs). Each radiofrequency application was delivered with 15-30W for &lt;30s along the P-LPVs and 30-40W for 40-60s along the others. Results: In 63 reconnected gaps, the right-PVs had more gaps in the anterior and posterior carina, while the left-PVs had more in the posterior carina than elsewhere, respectively (P&lt;0.05). The P-RPVs and P-LPVs had significantly more gaps than the A-LPVs (17 A-RPVs, 21 P-RPVs, 6 A-LPVs, and 19 P-LPVs; P&lt;0.05). The mean CF in the A-RPVs and P-RPVs (odds ratios (ORs), 0.916 and 0.854; P=0.014 and &lt;0.001, respectively) and Force-Power-Time Index (FPTI) in the A-LPVs (OR, 0.99; P=0.012) were significant negative predictors of PVRs. According to the receiver operating characteristics analysis, at optimal cutoffs of mean CFs of 18g (A-RPVs) and 12g (P-RPVs), and FPTI of 36,737g.W.s (A-LPVs), the sensitivity and specificity for predicting PVRs were 81.3% and 61.9%, 71.3% and 52.9%, and 58.6% and 100%, respectively. Conclusions: The carina regions can be common sites for PVRs despite a higher CF and FPTI. An optimal CF and FPTI may be needed to prevent PVRs during an initial CPVI, especially in the RPVs and A-LPVs.

Atrial tachycardias utilizing the Ligament of Marshall region following single ring pulmonary vein isolation for atrial fibrillation.

Organized atrial tachycardias (OATs) after pulmonary vein isolation (PVI) procedure are common. Arrhythmia mechanisms include mitral annular, ring gap, or roof-dependent gap-related flutters. In this series, we describe a mechanism of arrhythmia utilizing the ridge between left pulmonary vein (PV) and left atrial appendage (LAA) in the Ligament of Marshall (LOM) region. Five tachycardias involving the LOM region were identified from a group of 240 patients who underwent a single ring PVI procedure for symptomatic atrial fibrillation. The common characteristics of these tachycardias were the endocardial breakout over a broad area adjacent to the LOM region, presence of presystolic or mid-diastolic potentials, and abolition by ablation of the presystolic or mid-diastolic potentials remote from the endocardial breakout site. In all five cases, tachycardias were present after isolation of the veins and posterior left atria. All demonstrated characteristic areas of very slow conduction in the LOM region highlighted by presence of either low voltage, long duration fractionated potentials, or mid-diastolic potentials with a fixed temporal relationship to the subsequent endocardial activation. The pattern of activation and termination of tachycardia during ablation was consistent with an arrhythmia utilizing an electrically insulated tract within LOM and the PV-LAA ridge region. We identified a pattern of arrhythmias involving a concealed presystolic component and a broad endocardial breakout site related to the LOM region. Successful ablation site involved careful identification of small diastolic potentials in the LAA/ridge region or adjacent to the coronary sinus.

Abstract 214: Effect of Intensive Lipid-Lowering Therapy on Epicardial Adipose Tissue in Patients Undergoing Pulmonary Vein Isolation for Atrial Fibrillation

Background: The epicardial adipose tissue (EAT) has been identified as a sensitive marker of cardiometabolic risk. Recent evidence suggests efficacy of long-term statin therapy in reducing the EAT in patients with coronary artery disease. Whether the volume of EAT changes in patients with atrial fibrillation (AF) treated with a statin for a short time period is currently unknown. Methods: A population of AF patients undergoing pulmonary vein isolation was randomized to receive either 80 mg/day of atorvastatin (n=51, 44 males, age 55±10 years) or placebo (n=51, 41 males, age 56±10) for a 3 month period. EAT volume was assessed by cardiac computed tomography at baseline and after 3-month follow-up. Results: Patients randomized to statin treatment exhibited significant decreases in EAT volume (baseline vs follow-up: 105.8 ± 52.95 vs 103.05 ± 52.55 cm3, p = 0.05), C-reactive protein (2.97 ± 4.3 mg/L vs 2.03 ± 2.2 mg/L, p &lt; 0.05), total cholesterol (182.5 ± 36.9 vs 129.3 ± 40.6 mg/dL, p &lt; 0.001), and low density lipoprotein-cholesterol (111.88 ± 28 vs 61 ± 32.6 mg/dL, p &lt; 0.001) at follow-up, while the body mass index did not vary (29.42 ± 5.2 vs 29.11 ± 4.8 kg/m2, p = 0.28). No changes were seen in the placebo group. Conclusions: Short-term high-dose statin therapy significantly reduced the volume of EAT in AF patients. EAT volume modulation might be an important mechanism by which statins may influence cardiovascular risk.

Surgical revision after percutaneous mitral valve repair by edge-to-edge device: when the strategy fails in the highest risk surgical population

Percutaneous edge-to-edge devices for non-surgical repair of mitral valve regurgitation are under clinical evaluation in high-risk patients deemed not suitable for conventional surgery. To address guidelines for initial therapy decision, we here report on 13 cases of surgery after failed percutaneous edge-to-edge mitral valve repair or attempted repair, and discuss methodology and prognostic factors for operative outcome in this high-risk situation. Thirteen patients referred to our cardiothoracic unit after failed percutaneous mitral valve repair or attempted repair using the edge-to-edge technique, were treated surgically for mitral valve failure between June 2010 and December 2012. Pathology of mitral valve before and after interventional mitral valve repair (especially prevalent mode of failure) was evaluated and classified for each individual patient by echocardiography and intraoperative direct visualization. Number of implanted edge-to-edge devices were identified. Preoperative risk scores were matched with intraoperative observations and histopathological findings of valve tissue. Postoperative morbidity and mortality were analysed with respect to mitral valve and patient-related data. Three of 10 patients were referred with severe mitral valve regurgitation/stenosis after initially successful percutaneous edge-to-edge therapy or attempted therapy. In 3 patients, ≥ 2 edge-to-edge devices were implanted leading to very tight edge-to-edge leaflet connection and fibrosis. All patients underwent successful surgical mitral valve replacement and concomitant complete cardiac surgery (CABG, aortic or tricuspid valve surgery, ASD closure and pulmonary vein isolation for atrial fibrillation). The likelihood of repair was reduced with respect to multiple edge-to-edge technology. One device could not be harvested surgically because of embolization. One patient died on the second postoperative day due to sepsis with multiple organ failure. The remaining 12 patients were discharged with excellent valve prosthesis function and followed up to 2 years post-surgery. The current long-term survival rate is 77%. Our series demonstrate that highest risk patients can survive mitral valve surgery after failed multiple edge-to-edge interventional mitral valve repair. As long-term results of the MitraClip therapy are pending, we recommend close meshed follow-up of patients treated with the MitraClip device, especially within the first year of the index procedure as delays in salvage management, interventional or surgical, when the index procedure fails may increase morbidity and mortality.

Optimal observation time after completion of circumferential pulmonary vein isolation for atrial fibrillation to prevent chronic pulmonary vein reconnections

PurposeTo identify predictors of chronic pulmonary vein (PV) reconnection (CPVR) after successful circumferential PV isolation (CPVI) for atrial fibrillation (AF). Materials and methodsA total of 718 PVs from 181 consecutive AF patients (141 males, median age 61years, 92 paroxysmal AF) who underwent a second ablation procedure for recurrent AF were retrospectively analyzed. ResultsDuring the second procedure, a CPVR was observed in 477 PVs (66.4%) among 169 patients. In a multiple logistic regression analysis, the observation time after the final completion of the PVI (OT-final) was a significant negative predictor (odds ratio 0.980; P<0.001). A receiver operating characteristic analysis demonstrated that the greatest area under the curve was for the OT-final (0.670). At an optimal cutoff of 35min, the sensitivity and specificity for predicting a CPVR were 66.9% and 60.6%, respectively. By Kaplan Meier analysis, CPVR was more frequent in PVs with an OT-final of <35min than ≥35min (log-rank test, P=0.018). In a vessel-by-vessel analysis, the OT-final at all PV sites was a significant negative predictor, while male gender in the right PVs and left-inferior PV, number of RF applications for the ipsilateral CPVI in the right PVs and left-superior PV, and major PV diameter in the left-superior PV were significant positive predictors of a CPVR (all P<0.05). ConclusionsAn optimal observation time (≥35min in this study) to determine whether PVI is successfully completed during the initial CPVI for AF may be needed to prevent a CPVR and subsequent AF recurrence thereafter.

Does obstructive sleep apnea suppress reverse remodeling of left atrium after successful pulmonary vein isolation for atrial fibrillation?

Does obstructive sleep apnea suppress reverse remodeling of left atrium after successful pulmonary vein isolation for atrial fibrillation?

Ischemic Esophageal Ulceration That Developed After an Early Endoscopic Surveillance in a Patient Receiving Catheter Ablation for Atrial Fibrillation

An atrioesophageal fistula is a rare but lethal complication that develops a week to several weeks after the pulmonary vein isolation for atrial fibrillation.1 Because the thermal injury resulting from radiofrequency energy application peaks within a few days,2 the ischemic or gastric reflux injury that progresses during the following weeks was assumed to play a pivotal role in the delayed development of this complication.1 However, no report has ever precisely described the nature of the ischemic injury. Here, we report a case of an esophageal ulceration that developed after an early endoscopic surveillance that was assumed to be the result of the ischemic injury observed in patients receiving extensive pulmonary vein isolation for atrial fibrillation. A 55-year-old man with a symptomatic paroxysmal atrial fibrillation underwent extensive pulmonary vein isolation under conscious sedation. After a simultaneous pulmonary vein angiogram and esophagogram (Figure 1A), the extensive pulmonary vein isolation was carried out with an open-irrigation-tip catheter (ThermoCool, Biosense, Webster, Diamond Bar, CA). A maximum of 15 to 20 W with a duration of 20 …

第15回体表心臓微小電位研究会 シンポジウムP波加算平均心電図の臨床的意義 心房細動患者に対するカテーテル・アブレーションの再発の予測:P波加算平均心電図を用いた検討.

第15回体表心臓微小電位研究会 シンポジウムP波加算平均心電図の臨床的意義 心房細動患者に対するカテーテル・アブレーションの再発の予測:P波加算平均心電図を用いた検討.

Combined Dominant Frequency and Complex Fractionated Atrial Electrogram Ablation After Circumferential Pulmonary Vein Isolation of Atrial Fibrillation

Atrial substrates with high-dominant frequency (DF) and complex fractionated atrial electrogram (CFAE) sites have sources maintaining atrial fibrillation (AF) and are potential AF ablation targets. This study aimed to evaluate an approach of circumferential pulmonary vein isolation (PVI) followed by a DF and CFAE site ablation. Fifty consecutive AF patients (23 paroxysmal, 9 persistent, and 18 longstanding persistent) underwent ablation, using NavX. When AF continued after circumferential PVI, high-DF sites of ≥ 8 Hz and then continuous left atrial (LA) CFAE sites defined by fractionated intervals (FI) of ≤50 milliseconds including the coronary sinus and right atrium were targeted. A total of 45.1% of high-DF and 48.1% of continuous CFAE sites significantly decreased after PVI (P < 0.001). The mean LA DF and FI significantly decreased and prolonged, respectively, after PVI (P < 0.001). Only 14.1% of all high-DF sites after PVI overlapped with continuous CFAE sites. AF terminated at high-DF sites in 11 (22%) patients and continuous CFAE sites in 1 (2%). AF could be induced in only 8% of patients after the procedure. The mean LA DF value before ablation was significantly lower in those without recurrence (P = 0.003). AF freedom on antiarrhythmic drugs was 96% and 59%, respectively, in the paroxysmal and nonparoxysmal AF patients (89% persistent and 44% longstanding persistent) after 1 procedure over a 12-month follow-up. A combined high-DF and continuous CFAE site ablation in all chambers after circumferential PVI may be effective in the paroxysmal and persistent AF patients.

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

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. VATS-PVI consisted of PVI and ganglionic plexus ablation in 29 patients (mean age, 59 ± 7years; 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 6months postprocedure. P wave dispersion was derived from the 12 lead ECG. 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 ± 4.6ms to 131 ± 3.6ms (p < 0.01) but shortened to 99 ± 3.2ms after 6months (p < 0.01). PWA was 5.60 ± 0.32mV*ms at baseline, 6.44 ± 0.32mV*ms post-VATS-PVI (P = NS), and 5.40 ± 0.28mV*ms after 6months (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 ± 2.5ms post-VATS-PVI (p = 0.30) and to 61 ± 3.4ms after 6months (p < 0.05). PWD increases significantly directly after successful VATS-PVI in both groups. There was significant decrease in PWD after 6months. 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.