Severe hypoxemia after radiofrequency ablation for atrial fibrillation in palliatively repaired tetralogy of Fallot: A case report

BACKGROUND Patients with tetralogy of Fallot(TOF)often have arrhythmias,commonly being atrial fibrillation(AF).Radiofrequency ablation is an effective treatment for AF and does not usually cause severe postoperative hypoxemia,but the risk of complications may increase in patients with conditions such as TOF.CASE SUMMARY We report a young male patient with a history of TOF repair who developed severe hypoxemia after radiofrequency ablation for AF and was ultimately confirmed to have a new right-to-left shunt.The patient subsequently underwent atrial septal occlusion and eventually recovered.CONCLUSION Radiofrequency ablation may cause iatrogenic atrial septal injury;thus possible complications should be predicted in order to ensure successful treatment and patient safety.

Segmental radiofrequency ablation of pulmonary vein ostia for patients with refractory paroxysmal atrial fibrillation using multi-slice spiral computed tomography guidance

Objective： To evaluate the safety and clinical efficacy of segmental radiofrequency ablation of pulmonary vein （PV） ostia for patients with refractory paroxysmal atrial fibrillation （AF） under multi-slice spiral computed tomography （MSCT） guidance before the procedure. Methods： A series of 58 consecutive patients with refractory paroxysmal AF were enrolled to undergo segmental radiofrequency ablation ofPV ostia. The 36 male and 22 female patients with mean age of （57.4±9.5） （32-79） years and no obvious organic heart disease. Before ablation, patients received MSCT to generate 3-dimentional image of the left atrium （LA） and proximal PVs. Patients then underwent segmental radiofrequency ablation ofPV ostia using PV circular mapping catheter manipulated several times to ensure complete isolation between PVs and LA. Results： No complications occurred during the procedure. One patient developed delayed cardiac tamponade, which was drained percutaneously. The mean follow-up time was （17.1±9.3） months. Forty-one patients （95%） experienced improved quality of life one month after the procedure. Thirty-six patients （83%） showed stable sinus rhythm, while 10 patients （23%） required additional anti-arrhythmic drugs. AF returned≥1 time in 6 （14%） patients who underwent anti-arrhythmic drug therapy, but the number of episodes was less than that before the procedure. However, one patient experienced recurrent episodes of atrial flutter. Conclusion： It is safe and effective to perform segmental radiofrequency ablation of PV ostia for patients with refractory paroxysmal AF using MSCT guidance mappening.

Hemoptysis secondary to pulmonary vein stenosis after radiofrequency ablation for atrial fibrillation: A case report and literature review

Objectives: Pulmonary vein stenosis(PVS) is a known complication after radiofrequency ablation of atrial fibrillation(RAAF) and is often misdiagnosed owing to lack of awareness regarding PVS among noncardiologists.Misdiagnosis results in unnecessary treatment;therefore, greater understanding of PVS can improve the management of these patients.Methods: We report the case of a 38-year-old man with a history of RAAF who presented with massive hemoptysis.His symptoms persisted despite undergoing transcatheter bronchial artery embolization on two occasions.Results: Pulmonary computed tomography angiography revealed a completely occluded left superior pulmonary vein. Considering the patient’s history of RAAF, we diagnosed him with RAAF-induced PVS and performed left superior lobectomy after which hemoptysis did not recur.Conclusions: Unexplained massive hemoptysis should alert clinicians regarding the possibility of RAAF-induced PVS. Balloon angioplasty and stent placement are used to treat PVS;however, their efficacy is controversial considering the high recurrence rates associated with these interventions.

Endoscopic management of an esophagopericardial fistula after radiofrequency ablation for atrial fibrillation

A case is reported of a 76-year-old man with a past history of atrial fibrillation. A radiofrequency ablation procedure was suggested following several failed cardioversion attempts. However, an esophagopericardial fistula complicated the procedure. This life-threatening complication was successfully managed using both the placement of a covered esophageal stent and surgical pericardial and mediastinal drainage. In fact, no persisting fistula could be detected when the esophageal stent was removed seven weeks later. Atrioesophageal and esophagopericardial fistulas are two of the most severe complications associated with cardiological radiofrequency ablation procedures. They are responsible for majority of the deaths associated with this procedure. Despite the extremely high morbimortality associated with cardiothoracic surgery in such conditions, this treatment is the gold-standard for the management of such complications. This case report emphasizes the importance and efficacy of the endoscopic approach as part of a multidisciplinary management approach to this serious adverse event following radiofrequency ablation for atrial fibrillation.

RADIOFREQUENCY CATHETER ABLATION OF PERMANENT ATRIAL FIBRILLATION UNDER GUIDANCE OF CARTO-MERGE TECHNIQUE

Objective To investigate the feasibility and effectiveness of radiofrequency catheter ablation (RFCA) to treat permanent atrial fibrillation (AF) under the guidance of Carto-Merge technique. Methods Fifteen male patients with permanent AF underwent RFCA under the guidance of Carto-Merge technique. The mean age was 54.00±10.44 years, and duration of AF was 23.66±14.93 months. Cardiac magnetic resonance angiography (MRA) was performed to obtain pre-procedural three-dimensional (3D) images on the anatomy of left atrium (LA) and pulmonary veins (PVs) before RFCA procedure. Then the electroanatomical map was integrated with 3D images of MRA to form Carto-Merge map that guided step-by-step ablation strategy of permanent AF. Circumferential PV ablation was performed first until complete PVs electric isolation confirmed by Lasso catheter. If AF was not terminated, lesion lines on roof of LA, mitral isthmus, and tricuspid isthmus were produced. Results The episodes of AF were terminated during RFCA in 2 patients, by direct current cardioversion in the remaining 13 patients. Transient AF occurred in 2 patients after ablation on 1st day and 1st week respectively, AF terminated spontaneously not long after taking metoprolol. One patient developed persistent atrial flutter (AFL) in 2 months after procedure and AFL was eliminated by the second ablation. Persistent AF recurred on 1st day, 1st and 5th week respectively in 3 patients, and did not terminate after 3 months even though amiodarone was given. The remaining 12 patients were all free of AF during 2-11 months of follow-up. The recent success rate for RFCA of permanent AF was 80%. Conclusions Carto-Merge technique can effectively guide RFCA of permanent AF. When combined with single Lasso mapping, it can simplify the mapping, lower expenses, and enhance the success rate of RFCA of permanent AF.

Successful Anesthetic Management for Surgical Repair of Atrio-Esophageal Fistula Following Radiofrequency Ablation for Atrial Fibrillation

Introduction: Atrio-esophageal fistula is a rare but often fatal complication of radiofrequency ablation for atrial fibrillation. Here we report a successful case in anesthetic management of surgical repair of atrio-esophageal fistula. Case Report: The patient was a 56-year-old man status post radiofrequency ablation for atrial fibrillation one month before presenting with fever and symptoms and signs of cerebral emboli. He was diagnosed as having atrio-esophageal fistula, which required emergent surgical repair. In the operating room, rapid sequence induction was performed with avoidance of positive pressure ventilation before securing airway. Double lumen tube was used for lung isolation for left thoracotomy. Upon exploration, a small fistula was identified. Both atrial and esophageal defects were ligated and an intercostal muscle flap was placed. The patient’s heart rhythm was atrial flutter/atrial fibrillation with marginal hemodynamics during the procedure, but cardioversion was delayed until the fistula was repaired and no remaining air, blood clot or gastric content in the heart was confirmed by epicardial ultrasound. The patient tolerated the surgery and was transferred to ICU, intubated and ventilated. He recovered from surgery and was transferred to a rehabilitation hospital with residual expressive aphasia. Conclusion: We had a successful case in anesthetic management for surgical repair of atrio-esophageal fistula by preventing massive bleeding as well as multiple air embolization through the fistula.

Design and Baseline Patient Characteristics of the Prospective, Observational, Multicenter and Multinational Cohort Study Comparing Radiofrequency with Cryoablation for Pulmonary Vein Isolation in Patients with Atrial Fibrillation—The Freeze Cohort Study

Aims: The FREEZE-cohort study (NCT 01360008) is a prospective observational, multicenter and multinational study to evaluate safety and effectiveness of cryoballoon ablation for pulmonary vein isolation as compared to radiofrequency ablation in patients with paroxysmal or persistent atrial fibrillation (lasting < one year) under the conditions of clinical routine. Methods and Results: The study started in 2011 and anticipates inclusion up to 2000 patients in each of the two treatment groups. A total of 37 centers from 8 countries worldwide, all experienced in at least one of the two ablation techniques, participate in the study. The primary outcome parameter of the study is defined as atrial fibrillation recurrence rate during twelve months of follow-up. Secondary outcome parameters include primary success rates, complication rates in general, specific complications with respect to phrenic nerve palsy and pulmonary vein stenosis, radiation exposure, clinical course including death and repeat ablation. Finally specific procedural aspects will be evaluated in a descriptive manner. Preliminary data of the first 1882 patients show that in clinical practice cryoablation is preferentially performed in patients with paroxysmal atrial fibrillation, whereas application of radiofrequency ablation is equally distributed between patients with persistent and paroxysmal atrial fibrillation. Conclusion: Based on multi-center and multi-national data the FREEZE-cohort study will provide important information on long-term efficacy, clinical effectiveness, complication rates and procedural differences between atrial fibrillation patients treated with either cryoablation or radiofrequency ablation.

The correlation between MFAP4 and recurrence and clinical outcome of atrial fibrillation after radiofrequency catheter ablation

Objective:To investigate the correlation between Microfibrillar-associated protein 4(MFAP4)and recurrence and clinical outcome of atrial fibrillation(AF)after radiofrequency catheter ablation(RFCA).Methods:A total of 101 patients with AF admitted to our department from December 2018 to January 2020 were treated with RFCA.The average follow-up period was(11.91±0.38)months.They were divided into recurrence group and non-recurrence group according to whether they had recurrence of AF.The levels of MFAP4,transforming growth factor-β1(TGF-β1),cardiac ultrasound indexes,body mass index(BMI)and major cardio-cerebral vascular events were compared between the two groups.The receiver operating characteristic(ROC)curve was drawn to analyze the predictive value of MFAP4 for recurrence of AF after RFCA.Results:The levels of MFAP4,TGF-β1,left atrial diameter(LAD)and BMI in the recurrent group were higher than those in the non-recurrent group(P<0.05).The left ventricular ejection fraction(LVEF)in the recurrent group was lower than that in the non-recurrent group(P<0.05).The levels of MFAP4,TGF-β1 and LAD in the patients of recurrent paroxysmal AF and persistent AF after RFCA were higher than those in the respective non-recurrent patients(P<0.05).MFAP4 was positively correlated with TGF-β1 and LAD(P<0.05).Logistic regression analysis showed that MFAP4,TGF-β1,and LAD were independent risk factors for recurrence of AF after RFCA.The ROC curve analysis showed that the area under the ROC curve of MFAP4 for predicting recurrence of AF after RFCA was 0.888(P=0.000),and the optimal cut-off value was 19.295ng/ml,with a sensitivity of 77.3%and a specificity of 77.2%.The incidence of readmission and total adverse events in recurrence group was significantly higher than that in non-recurrence group(P<0.05).Conclusions:MFAP4 was significantly increased in patients with recurrence after RFCA of AF,which was one of the independent risk factors for recurrence after RFCA of AF,and had certain clinical application value.

Simple hematological predictors of AF recurrence in patients undergoing atrial fibrillation ablation

Backgound Red cell distribution width(RDW) and neutrophil-to-lymphocyte ratio(NLR) are simple hematologic indices that have been used to predict adverse outcomes in different clinical settings. The aim of our study is to determine whether RDW and NLR can predict atrial fibrillation(AF) recurrence in patients undergoing AF ablation. Methods Consecutive patients, without known hematological disorders, who underwent AF catheter ablation between January 2014 and April 2017 were enrolled into this study. Blood samples were taken one day before and five hours after the ablation procedure. Results A total of 346 patients(224 males(65%), mean age: 59 ± 11 years old) were included. After a mean follow up of 26.2 ± 12.1 months, 80(23.1%) patients experienced late AF recurrence(defined as any recurrence after the blanking period of three months), while 97(28%) patients experienced early AF recurrence during the blanking period. Univariate analysis showed that early arrhythmia recurrence, type of AF and NLR after the procedure were significantly associated with late AF recurrence, while early arrhythmia recurrence and NLR remained significant in multivariate analysis. RDW was not associated with late AF recurrence. None of the parameters above predicted early arrhythmia recurrence. Conclusions Simple and inexpensive hematological indices such as NLR should be evaluated for their ability to predict AF recurrence in patients undergoing catheter ablation in larger prospective studies.

A three-year longitudinal study of the relation between left atrial diameter remodeling and atrial fibrillation ablation outcome

Background The long-term prognostic influence of left atrial diameter （LAD） remodeling on the status of post-radiofrequency catheter ablation （RI CA） atrial fibrillation （AF） is unclear. This study employed a two-stage model from 3-year echocardiographic data to ascertain whether the two-stage model predicts RFCA outcome more favorably than models using the baseline LAD. Methods Data were retrospectively collected from 263 consecutive patients with drug-refractory AF undergoing RFCA. Regular echocardiographic measurements of LAD were performed at baseline, 1, 3, 6, and 12 months and then every 6 months after RFCA. Sex, age, type of AF, number of RFCA, and AF status were recorded. We obtain the actual （predicted） 3-year LAD using a longitudinal linear mixed model （1st stage）. Logistic regression models based on the baseline LAD （Model 1）, actual （predicted） 3-year LAD （Model 2） （2nd stage）, and observed 3-year LAD （Model 3） were constructed to predict RFCA outcome. The area under the receiver operating characteristic curve （AUC） were used to assess the performance of models. Results The lowess smoothed curve indicated that the LAD declined over the first three months and remained stable up to 36 months after RFCA. The degree of LAD reduction was significantly influenced by the baseline LAD. Non-paroxysmal AF, large LAD and female gender were significant predictors of AF recurrence. Model 2 had the largest AUC among the three models. Conclusions This longitudinal study-based two-stage model outperforms the original logistic model using the baseline LAD. Non-paroxysmal AF, larger LAD and female gender are significant predictors of RFCA failure.

Treatment of Supraventricular Arrhythmias by Transcatheter Radiofrequency Ablation： The Experience of the Electrophysiology Unit of the University Hospital

TC-RF （transcatheter radiofrequency） ablation has an important role in the treatment ofSVA （supraventricular arrhythmias）. The indication to TC-RF ablation is usually made to improve the patient＇s quality of life through the elimination of the arrhythmic substrate. The objective of this study is to make a brief review of the literature and to report the Electrophysiology Unit experience of the Cardiovascular Department of the University Hospital of Trieste. From the study, it can be found that about one thousand of patients are visited annually in the Cardiovascular Department of the University Hospital of Trieste （1,019 ± 71/year over the past five years）. The acute success rate of atrial fibrillation and flutter ablation procedures was respectively 93.9% and 97.9% with a relapse rate of 30% and 10% at 12 month. Accessory pathways and nodal atrio ventricular re-entry tachycardia ablation procedures had an acute success rate of respectively 91.1% and 96.6% with a relapse rate of 10% at 12 months. The overall complication rate was 5%. Catheter ablation is an effective therapy for SVA treatment. It can often be definitive, and it is generally superior to drug therapy, with a low complication rate. The improvement in patients＇ quality of life is associated with a reduced need for access to health services.

Rotor identification by body surface mapping and endocardial mapping：impact on atrial fibrillation ablation

为及时反映海外心脏病学领域的最新进展，努力缩短国内外心电学研究的差距，自本期起，本刊推出“海外论坛”栏目。本栏目主要刊发国内外心脏病学研究领域前沿成果的专题述评、综述和重要学术会议快报等，形式不拘。欢迎海内外学者惠赐大作!

Role of a new inflammation predictor in predicting recurrence of atrial fibrillation after radiofrequency catheter ablation

BACKGROUND Radiofrequency catheter ablation(RFCA)has become an important strategy for treating atrial fibrillation(AF),and postoperative recurrence represents a significant and actively discussed clinical concern.The recurrence after RFCA is considered closely related to inflammation.Systemic immune inflammation index(SII)is a novel inflammation predictor based on neutrophils,platelets,and lymphocytes,and is considered a biomarker that comprehensively reflects the immune inflammatory status of the body.AIM To explore the predictive effect of the SII on AF recurrence after RFCA and its predictive value in combination with the existing APPLE score for AF recurrence after RFCA in patients with non-valvular AF(NVAF).METHODS We retrospectively included 457 patients with NVAF first receiving RFCA and classified them into the recurrent or non-recurrent group.We also investigated the predictive role of SII on AF recurrence following RFCA.Finally,we explored and compared the additional predictive value of the SII after combining with the APPLE score.RESULTS After 12 months of follow-up,113(24.7%)patients experienced recurrence.High SII has been demonstrated to be an independent predictor for postoperative AF recurrence.Receiver operating characteristic and decision curve analysis(DCA),as well as net reclassification improvement(NRI)and integrated discrimination improvement(IDI)results,showed that SII combined with the APPLE score had higher predictive efficiency than using the SII or APPLE score alone.The area under the curve of the combined model(0.662,95%confidence interval:0.602-0.722)significantly increased compared with that of the SII and APPLE scores alone(P<0.001).The combined model resulted in an NRI of 29.6%and 34.1%and IDI of 4.9%and 3.5%in predicting AF recurrence compared with the SII and APPLE scores alone,respectively(all P<0.001).The SII,APPLE score,and their combination demonstrated greater clinical utility than did the treat-all and treat-none strategies over the 20–80%risk threshold according to the DCA.CONCLUSION The SII was a predictor of recurrence after RFCA of AF.Moreover,the SII enhanced the predictability of the APPLE score for post-RFCA AF recurrence,providing valuable insights for physicians to optimise patient selection and develop personalised treatment plans.

Severe esophageal injury after radiofrequency ablation-a deadly complication

Various degrees of esophageal injury have been described after radiofrequency ablation performed for treatment of atrial fibrillation. The main mechanism of injury is thermal and may lead to a range of esophageal mucosal changes, some clinically insignificant, however when deep ulceration occurs, this may be further complicated by perforation and mediastinitis, a rare but life threatening sequelae. We present a case of a severe esophageal injury leading to mediastinitis, with interesting endoscopic findings.

Tale of fat and fib-cardiac lipoma managed with radiofrequency ablation: A case report

BACKGROUND Cardiac lipoma and lipomatous hypertrophy of interatrial septum(LHIS)are very rare disorders with distinct pathological features.While cardiac lipoma is a well-circumscribed encapsulated tumor of mature adipocytes,LHIS is due to entrapment of fat cells in the interatrial septum during embryogenesis.Although a biopsy is the definitive diagnostic test,these disorders can be differentiated by a cardiac magnetic resonance imaging(MRI).Treatment of LHIS is not warranted in asymptomatic patients.In symptomatic patients,surgical resection is the only recommended treatment,which has shown to improve good long-term prognosis.CASE SUMMARY A 63-year-old Caucasian woman with past medical history significant for hypertension,hypothyroidism,right breast ductal cell carcinoma treated with mastectomy and breast implant,platelet granule disorder,asthma requiring chronic intermittent prednisone use,presented to the outpatient cardiology office with recent onset exertional dyspnea,palpitations,weight gain and weakness.Initial workup with electrocardiogram and holter monitor did not reveal significant findings.During the subsequent hospitalization for community acquired pneumonia,the patient developed symptomatic paroxysmal atrial fibrillation.Transthoracic echocardiogram showed a right ventricular mass.A biopsy was not pursued given the high risk of bleeding due to platelet granule disorder.Cardiac MRI showed characteristic features consistent with cardiac lipoma and LHIS.Prednisone was discontinued.Genetic testing for arrhythmogenic right ventricular dysplasia and 24-h urine cortisol test was negative.As multiple attempts at rhythm control failed with sotalol and flecainide,pulmonary vein isolation and right atrial isthmus radiofrequency ablation were done.She is in follow-up with symptomatic relief and no recurrence of atrial fibrillation for 10 mo.CONCLUSION Benign fatty lesions in heart include solitary lipoma,lipomatous infiltration and lipomatous hypertrophy of interatrial septum.Although transvenous biopsy provides a definitive diagnosis,Cardiac MRI is superior to computed tomography and aids in differentiating benign from malignant lesions.Surgical excision of cardiac lipoma along with capsule and pedicle removal generally prevents recurrence,but with our patient’s unusual tumor features and comorbidities proscribed a surgical approach.Symptom management with antiarrhythmics and ablation techniques were successfully utilized.

A three-pulmonary vein isolation approach to treat paroxysmal atrial fibrillation

Objective To investigate the safety and efficacy of a 3-pulmonary vein (PV) isolation approach in treating paroxysmal atrial fibrillation (AF). Methods Radiofrequency catheter ablation was used to eliminate PV potential in 11 patterns with frequent paroxysmal AF refractory to anti-arrhythmic agents. During sinus rhythm, PV potential was mapped in the left and right superior PVs and left inferior PV. The procedural success was defined as the elimination of PV potential in the 3 PVs. Restults PV potential was identified and abolished in a total of 24 PVs, mostly in the left and right superior PV. There was no pulmonary stenosis or other complications during or after the procedures. AF recurred in one patient after an average of 12 ± 3 month follow-up. Conclusions PV potemials were present mostly in the left or right superior PV. The 3-PVs isolation approach is safe and effective in preventing drug-resistant paroxysmal AF.

Catheter ablation using pulsed-field energy:Do we finally have the magic wand to defeat atrial fibrillation?

Clinical outcomes of catheter ablation remain suboptimal in patients with atrial fibrillation(AF),particularly in those with persistent AF,despite decades of research,clinical trials,and technological advancements.Recently,pulsed-field ablation(PFA),a promising non-thermal technology,has been introduced to improve procedural outcomes.Its unique feature of myocardial selectivity offers safety advantages by avoiding potential harm to vulnerable adjacent structures during AF ablation.However,despite the global enthusiasm within the electro-physiology community,recent data indicate that PFA is still far from being a“magic wand”for addressing such a complex and challenging arrhythmia as AF.More progress is needed in mapping processes rather than in ablation technology.This editorial reviews relevant available data and explores future research directions for PFA.

Radiofrequency ablation for treating paroxysmal supraventricular tachycardia complicated by atrial fibrillation： A single-center retrospective analysis

The effect of selective radiofrequency ablation for treating paroxysmal supraventricular tachycardia （PSVT） and its associated paroxysmal atrial fibrillation （PAF） was assessed. Methods Data were collected retrospectively from patients diagnosed of PSVT and subsequently treated with radiofrequency ablation. Regular monthly follow-up by dynamic electrocardiography （ECG） was performed. Incident rates of atrial fibrillation before and after ablation were compared. Results 382 PSVT patients with 58 having atrial fibrillation were en- rolled. The order of complicated PAF from high to low in these patients was displayed as： atrial tachycardia （AT）, atrioventricular reentrant tachycardia （AVRT） and atrioventricular nodal reentrant tachycardia （AVNRT）. Among AVRT patients, PAF was more frequent in patients having accessory pathways. AVNRT patients had significant- ly lower PAF rate comparing to other patients. PAF incident rate was significantly reduced by radiofrequency ablation therapy. Conclusion We advise regular dynamic ECG for PSVT patients, especially those with atrial flutter, AT or pre-excitation syndrome. Selective radiofrequency ablation is a feasible approach for treating AF complicated PSVT patients.

Single dose of ibutilide for conversion of persistent atrial fibrillation after radiofrequency ablation

Background Patients with persistent or permanent atrial fibrillation （AF） often need direct current cardioversion after radiofrequency ablation. The aim of this study was to investigate the effectiveness and safety of ibutilide for cardioversion of persistent or permanent atrial fibrillation after radiofrequency ablation and the factors related to conversion. Methods Patients with persistent or permanent atrial fibrillation were treated with combined ablation strategy including circumferential pulmonary vein isolation, linear ablation and CAFE potential ablation. If AF was not terminated after ablation, ibutilide was used for cardioversion （1 mg, intravenous injection in 10 minutes）. These patients were divided into a conversion group and a non-conversion group according to whether AF was converted to sinus rhythm within 30 minutes after administration. ECG monitoring was performed during the injection of ibutilide. Atrial waves recorded by coronary sinus electrodes were measured for calculating average wavelength of AF waves in six seconds. The QT interval was measured immediately after conversion and 2 hours after injection of ibutilide.Results Forty patients whose AF was not converted to sinus rhythm after radiofrequency ablation were given an intravenous injection of ibutilide. Of the 40 patients, 29 cases were converted to sinus rhythm, with a conversion rate of 72.5%. The average conversion time was （13.2±5.5） minutes. Compared with the conversion group, patients in the non-conversion group had a longer history of AF （9.4±5.3） years vs. （4.3±2.8） years, P 〈0.05）, and a markedly enlarged left atrium （47.3±2.9） mm vs. （42.1±4.5） mm, P〈0.05）. There were no significant differences in gender, age, body mass index and left ventricular function between the two groups. Ibutilide significantly prolonged the average wavelength of the AF wave （171.8±29.5） ms vs. （242.0±40.0） ms, P 〈0.001）. Two hours after ibutilide treatment, the QT interval was significantly shortened （421.0±24.7） ms vs. （441.0±37.4） ms, P〈0.05）. No cases of serious arrhythmias or other adverse reactions were found.Conclusions A single dose of ibutilide for conversion of persistent or permanent AF after radiofrequency ablation is safe and effective.