Atrial flutter without structural heart disease in pediatrics: a retrospective review of cases in the Hospital Infantil Miguel Servet, Zaragoza, Spain.

BACKGROUND: Atrial flutter is a rare condition in pediatrics that usually occurs as a late complication after surgery for congenital heart diseases, although it can also appear in structurally normal hearts. CLINICAL CASES: We conducted a retrospective study of cases of atrial flutter with no structural heart disease diagnosed in a pediatric population (between 0 and 15 years of age) during 2015-2021 in a tertiary hospital. A total of seven cases were diagnosed, with a clear predominance of males (6/7). Of the seven patients, five debuted in the perinatal period: two were diagnosed at 20 and 36 hours of life, and three, prenatally. Among these perinatal cases, more than half (3/5) were preterm. The treatment was electrical cardioversion. The evolution was satisfactory in these cases, and there were no tachycardias in their subsequent development. In contrast, when the debut occurred at a later age (5-7 years), it was associated with channelopathy (Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia), and electrical ablation of the ectopic focus was required due to poor response to pharmacological treatment. CONCLUSIONS: This study confirms the low incidence of this pathology in pediatrics and the benignity and good prognosis of neonatal flutter in most cases. The prognosis worsens when atrial flutter is diagnosed in older children, and the probability of concomitant associated heart disease increases.

INTRODUCCIÓN: El flutter o aleteo auricular es una patología poco frecuente en pediatría que suele presentarse como complicación tardía tras la cirugía de cardiopatías congénitas, aunque también puede aparecer en corazones estructuralmente normales. CASOS CLÍNICOS: Se llevó a cabo un estudio retrospectivo de los casos de flutter auricular sin cardiopatía estructural diagnosticados en una población pediátrica (entre 0 y 15 años de edad) durante el periodo 2015-2021 en un hospital terciario. En total fueron diagnosticados siete casos, con un claro predominio de varones (6/7). De los siete, cinco debutaron en periodo perinatal: dos fueron diagnosticados a las 20 y 36 horas de vida y tres de ellos, prenatalmente. Entre estos casos perinatales, más de la mitad (3/5) fueron pretérmino. El tratamiento fue la cardioversión eléctrica. La evolución fue satisfactoria en estos casos, y no se presentaron taquicardias en su evolución posterior. Por el contrario, cuando el debut se produjo en edades posteriores (5-7 años), se asoció con canalopatía (síndrome de Brugada y taquicardia ventricular polimorfa catecolaminérgica) que requirió de una ablación eléctrica del foco ectópico por escasa respuesta al tratamiento farmacológico. CONCLUSIONES: En este trabajo se confirma la baja incidencia de esta patología en pediatría, además de la benignidad y el buen pronóstico de flutter neonatal en la mayoría de casos. Cuando el diagnóstico se realiza en niños mayores, el pronóstico empeora, y aumenta la probabilidad de presentar de forma concomitante cardiopatías asociadas.

Electrical cardioversion of atrial arrhythmias with cardiac amyloidosis in the era of direct oral anticogulants.

AIMS: Atrial fibrillation (AF)/atrial flutter is common during cardiac amyloidosis (CA). Electrical cardioversion (EC) is a strategy to restore sinus rhythm (SR). However, left atrial thrombus (LAT) represents a contraindication for EC. CA patients with AF/atrial flutter have a high prevalence of LAT. We aimed to evaluate EC characteristics, LAT prevalence and risk factors, and AF/atrial flutter outcome in CA patients undergoing EC, predominantly treated with direct oral anticoagulants (DOACs). METHODS AND RESULTS: All patients with CA and AF/atrial flutter referred for the first time to our national referral centre of amyloidosis for EC from June 2017 to February 2021 were included in this study. In total, 66 patients (median age 74.5 [70;80.75] years, 67% male) were included with anticoagulation consisted of DOAC in 74% of cases. All patients underwent cardiac imaging before EC to rule out LAT. EC was cancelled due to LAT in 14% of cases. Complete thrombus resolution was observed in only 17% of cases. The two independent parameters associated with LAT were creatinine [hazard ratio (HR) = 1.01; confidence interval (CI) = 1.00-1.03, P = 0.036] and the use of antiplatelet agents (HR = 13.47; CI = 1.85-98.02). EC acute success rate was 88%, and we observed no complication after EC. With 64% of patients under amiodarone, AF/atrial flutter recurrence rate following EC was 51% after a mean follow-up of 30 ± 27 months. CONCLUSIONS: Left atrial thrombus was observed in 14% of CA patients listed for EC and mainly treated with DOAC. The acute EC success rate was high with no complication. The long-term EC success rate was acceptable (49%).

Pericardial effusion caused by accidently placing a Micra transcatheter pacing system into the coronary sinus.

BACKGROUND: Leadless pacemaker has been acknowledged as a promising pacing strategy to prevent pocket and lead-related complications. Although rare, cardiac perforation remains a major safety concern for implantation of Micra transcatheter pacing system (TPS). CASE PRESENTATION: A 83-year-old female with low body mass index (18.9 kg m-2) on dual anti-platelet therapy, was indicated for Micra TPS implantation due to sinus arrest and paroxysmal atrial flutter. The patient developed mild pericardial effusion during the procedure since the delivery catheter was accidentally placed into the coronary sinus for several times. Cardiac perforation with moderate pericardial effusion and pericardial tamponade was detected 2 h post-procedure. The patient was treated with immediately pericardiocentesis and recovered without further invasive therapy. CONCLUSION: Pericardial effusion caused by accidently placing a delivery catheter into the coronary sinus is rare but should be carefully considered in Micra TPS implantation, especially for those with periprocedural anti-platelet therapy.

Management Strategies for Atrial Fibrillation and Flutter in Patients with Transthyretin Cardiac Amyloidosis.

Atrial fibrillation (AF) and flutter (AFL) frequently complicate transthyretin cardiac amyloidosis (ATTR-CM). Management poses challenges as rate control drugs are poorly tolerated and data addressing tolerability and efficacy of rhythm control is limited. We report outcomes of AF/AFL in ATTR-CM in a single center observational study of patients seen at our Amyloidosis Center with wild-type or hereditary ATTR-CM diagnosed between 2005-2019 including 84 patients (average age 74 ± 10 years, 94% male) with 27.6 ± 22.8 months follow-up. AF/AFL occurred in 61 patients (73%). Rapid ventricular response was common as was attempted rate control. However, discontinuation of rate control drugs was frequent (80%), often for adverse effects. Rhythm control was attempted in 64%, usually with cardioversion (DCCV) or ablation. Post-DCCV recurrence was common (91%) and time to recurrence was similar with or without anti-arrhythmic drugs (5.8 months (IQR 1.9-12.5) vs 6.2 months (IQR 1.9-12.5) p = 0.83). Ablation was performed in 23% with AFL (all for typical AFL) with 14% recurrence after mean of 60.9 months. Ablation for AF was performed in 12% with 86% recurrence after median of 6.2 months (IQR 5.6-12.3). Most patients (62%) with rhythm control had subjective improvement (≥1 NYHA class or resolved palpitations). In conclusion, AF/AFL was common in our cohort. Rate control was poorly tolerated and often abandoned. Rhythm control led to symptomatic improvement in a majority of cases, but durable success was limited. DCCV was modestly successful and not significantly improved with anti-arrhythmics. Ablation was successful with typical AFL but had limited success in AF.

Lone Atrial Flutter in Children and Adolescents: Is It Really "Lone"?

Atrial flutter (AFL) in children and adolescents beyond the neonatal period in the absence of any underlying myocardial disease ("lone AFL") is rare and data is limited. Our study aims to present clinical and electrophysiological data of presumed "lone AFL" in pediatric patients and discuss the role of endomyocardial biopsy (EMB) and further follow-up. Since July 2005, eight consecutive patients at a median age of 12.7 (range 10.4-16.7) years presenting with presumed "lone AFL" after negative non-invasive diagnostic work-up had electrophysiological study (EPS) and induction of cavotricuspid isthmus (CTI) conduction block by radiofrequency (RF) current application. In 6/8 patients EMB could be taken. Induction of CTI conduction block was achieved in all patients. Histopathological examination of EMB from the right ventricular septum exhibited myocarditis or cardiomyopathy in 4/6 patients, respectively. During follow-up, 4/8 patients had recurrent arrhythmia (AFL n = 2, wide QRS complex tachycardia n = 1, monomorphic premature ventricular contractions n = 1) after the ablation procedure. 3/4 patients with recurrent arrhythmia had pathological EMB results. The remaining patient with recurrent arrhythmia had a negative EMB but was diagnosed with Brugada syndrome during further follow-up. Taking together results of EMB and further clinical course, only 3/8 patients finally turned out to have true "lone AFL". Our study demonstrates that true "lone AFL" in children and adolescents is rare. EMB and clinical course revealed an underlying cardiac pathology in the majority of the individuals studied. EMB was very helpful in order to timely establish the diagnosis of myocarditis or cardiomyopathy.

Ablation of Atrial Fibrillation Without Left Atrial Appendage Imaging in Patients Treated With Direct Oral Anticoagulants.

BACKGROUND: Many centers continue to routinely perform transesophageal echocardiograms before atrial fibrillation (AF) ablation procedures in patients treated with direct oral anticoagulants (DOACs). One study suggested that the procedures could be done without transesophageal echocardiogram but used intracardiac echocardiography imaging of the appendage from the right ventricular outflow. This study aimed to assess the safety of ablation for AF without transesophageal echocardiogram screening or intracardiac echocardiography imaging of the appendage in DOAC compliant patients. METHODS: All patients undergoing AF ablation at the Cleveland Clinic (2011-2018) were enrolled in a prospectively maintained data registry. All consecutive patients presenting with AF or atrial flutter on DOAC were included. Periprocedural thromboembolic complications were assessed. RESULTS: A total of 900 patients were included. Their median CHA2DS2-VASc score was 2 (interquartile range 1-3). All were on DOACs (333 rivaroxaban, 285 dabigatran, 281 apixaban, and 1 edoxaban). Thromboembolic complications occurred in 4 patients (0.3%): 2 ischemic strokes, 1 transient ischemic attack without residual deficit, and 1 splenic infarct; all with no further complications. Bleeding complications occurred in 5 patients (0.4%): 2 pericardial effusions (1 intraoperative, 1 after 30 days, both drained), 3 groin hematomas (1 of them due to needing heparin for venous thrombosis, none required interventions). No patients required emergent surgeries. CONCLUSIONS: In DOAC compliant patients who present for ablation in AF/atrial flutter, the procedures could be performed without transesophageal echocardiogram screening or intracardiac echocardiography imaging of the appendage; with low risk of complications.

Outcomes following cardioversion for patients with cardiac amyloidosis and atrial fibrillation or atrial flutter.

Atrial arrhythmias commonly occur in patients with cardiac amyloidosis (CA), but there is limited data on safety or efficacy of cardioversion (DCCV) for management of these rhythms in CA. We identified 25 patients with CA (20 with transthyretin (TTR) and 5 with light-chain (AL) amyloidosis) at Duke University who underwent DCCV for atrial arrhythmias and documented procedural success, complications, and long-term morbidity and mortality. While DCCV successfully restored sinus rhythm in 96% of patients, 36% of patients experienced immediate procedural complications (primarily bradycardia and hypotension), 80% had recurrence of atrial arrhythmias at 1 year, and 52% died at 3 years, highlighting short-term safety concerns, long-term inefficacy, and poor prognosis associated with symptomatic atrial arrhythmias requiring DCCV in CA.

Splenic rupture after elective cardioversion.

Splenic laceration and rupture are common phenomena among patients in a traumatic setting, especially in blunt trauma. Much more unusual, however, is splenic injury without a known insult. Several case reports and studies have been written about spontaneous splenic injury in patients with viral, haematological or malignant processes. Recently, we encountered a patient with a spontaneous splenic rupture and no preceding trauma apart from semielective cardioversion. Operative decision-making was complicated by the fact that he required systemic anticoagulation for atrial fibrillation. He eventually underwent splenectomy and made an uneventful recovery.

Atrial involvement in arrhythmogenic right ventricular cardiomyopathy patients referred for ventricular arrhythmias ablation.

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a heritable myocardium disorder that predominantly affects the ventricle. Little is known about atrial involvement. This study aimed to assess atrial involvement, especially the role of genotype on atrium in ARVC. METHODS: The incidence, characterization and predictors of atrial involvement were investigated. Nine known ARVC-causing genes were screened and the correlation between genotype and atrial involvement was assessed. RESULTS: Right atrium (RA) dilation, left atrium (LA) dilation, and sustained atrial tachyarrhythmias (ATa) were found in 45, 16 and 3 patients, respectively. Gene mutations were identified in 64 (64.0%) patients. Mutation carriers showed more RA dilation than noncarriers (54.7% vs. 27.8%, P = 0.009), and no difference in LA dilation and ATa. Multivariate analysis showed tricuspid regurgitation (OR: 18.867; 95% CI: 1.466-250.000; P = 0.024) increased the risk of RA dilation and decreased left ventricular ejection fraction (LVEF) (OR: 1.134; 95% CI: 1.002-1.272; P = 0.031) correlated with LA dilation, whereas genotype showed no significant effect. At a median follow-up time of 91 months, 7 patients died and 1 patient accepted heart transplantation. New-onset RA dilation, LA dilation, and sustained ATa were found in 8, 7, and 6 patients, respectively. Atrial involvement was not associated with the long-term survival. Despite mutation carriers showing more RA dilation, Kaplan-Meier analysis showed genotype was not associated with atrial involvement. CONCLUSION: Atrial involvement was common in ARVC. Tricuspid regurgitation and decreased LVEF increased the risk for atrial dilation. Genotype was not associated with atrial involvement.

WITHDRAWN: Electrical cardioversion for atrial fibrillation and flutter.

BACKGROUND: Atrial fibrillation increases stroke risk and adversely affects cardiovascular haemodynamics. Electrical cardioversion may, by restoring sinus rhythm, improve cardiovascular haemodynamics, reduce the risk of stroke, and obviate the need for long-term anticoagulation. OBJECTIVES: To assess the effects of electrical cardioversion of atrial fibrillation or flutter on the risk of thromboembolic events, strokes and mortality (primary outcomes), the rate of cognitive decline, quality of life, the use of anticoagulants and the risk of re-hospitalisation (secondary outcomes) in adults (>18 years). SEARCH METHODS: We searched the Cochrane CENTRAL Register of Controlled Trials (1967 to May 2004), MEDLINE (1966 to May 2004), Embase (1980 to May 2004), CINAHL (1982 to May 2004), proceedings of the American College of Cardiology (published in Journal of the American College of Cardiology 1983 to 2003), www.trialscentral.org, www.controlled-trials.com and reference lists of articles. We hand-searched the indexes of the Proceedings of the British Cardiac Society published in British Heart Journal (1980 to 1995) and in Heart (1995 to 2002); proceedings of the European Congress of Cardiology and meetings of the Joint Working Groups of the European Society of Cardiology (published in European Heart Journal 1983-2003); scientific sessions of the American Heart Association (published in Circulation 1990-2003). Personal contact was made with experts. SELECTION CRITERIA: Randomised controlled trial or controlled clinical trials of electrical cardioversion plus 'usual care' versus 'usual care' only, where 'usual care' included any combination of anticoagulants, antiplatelet drugs and drugs for 'rate control'. We excluded trials which used pharmacological cardioversion as the first intervention, and trials of new onset atrial fibrillation after cardiac surgery. There were no language restrictions. DATA COLLECTION AND ANALYSIS: For dichotomous data, odds ratios were calculated; and for continuous data, the weighted mean difference was calculated. MAIN RESULTS: We found three completed trials of electrical cardioversion (rhythm control) versus rate control, recruiting a total of 927 participants (Hot Cafe; RACE; STAF) and one ongoing trial (J-RHYTHM). There was no difference in mortality between the two strategies (OR 0.83; CI 0.48 to 1.43). There was a trend towards more strokes in the rhythm control group (OR 1.9; 95% CI 0.99 to 3.64). At follow up, three domains of quality of life (physical functioning, physical role function and vitality) were significantly better in the rhythm control group (RACE 2002; STAF 2003). AUTHORS' CONCLUSIONS: Electrical cardioversion (rhythm control) led to a non-significant increase in stroke risk but improved three domains of quality of life.

Splenic rupture following synchronised direct current cardioversion.

Atraumatic rupture of the normal spleen is a rare entity. Often, a triggering factor or minor physical event can be ascribed as the aetiology for rupture, including coughing, vomiting or minor medical procedures not involving the spleen. A 65-year-old man who was hospitalised for eosinophilic pneumonia developed haemodynamically unstable atrial flutter that necessitated urgent synchronised direct current cardioversion (DCCV). Two hours after successful cardioversion, he developed signs of an acute abdomen with free intraperitoneal fluid identified on bedside ultrasonography. Exploratory laparotomy revealed gross haemoperitoneum and splenic rupture requiring splenectomy. With exception of capsular defects and haemorrhage suggestive of organ rupture, the gross and histological examination of the spleen was otherwise unremarkable. The patient denied recent trauma. The cause of his spleen rupture was attributed to cardioversion and subsequent abdominal muscle contraction. This represents the first known case of splenic rupture associated with DCCV.

[Clinical features and outcomes of radiofrequency catheter ablation of atrial flutter in children].

Objective: To explore the clinical features of atrial flutter (AFL) and evaluate the efficacy of radiofrequency catheter ablation (RFCA) for AFL in children. Method: Data were collected and analyzed on 50 consecutive pediatric AFL patients (male 37/female 13) who underwent electrophysiology study and RFCA from February 2009 to November 2016 in a case observational study. The average age was (6.2±3.5) years and body weight was (23.7±13.5) kg. Heart structure was normal in 26 patients. Twenty-four patients had congenital heart disease (CHD) and among them 22 patients underwent repaired surgery before. Patients were followed-up for 1 month to 7 years after RFCA. Clinical features and the outcomes of RFCA in AFL patients were analyzed. Result: The average onset age was (4.2±3.3) years. Of these patients, 84% had persistent AFL and 16% paroxysmal AFL. AFL with sick sinus syndrome (SSS) occurred in 36% patients without statistically significant difference between the groups with and without CHD (38.9%(7/18) vs. 61.1%(11/18), respectively, P=0.239 5); 49 patients underwent RFCA except one case with atrial standstill during the procedure. The total acute success rate was 96%. The follow-up recurrence rate was 8%.No complication of the procedures was observed. The cavotricuspid isthmus-dependent AFL occurred in all patients without CHD. However, in the children with CHD after the repair surgery 10 (45%) cases were with cavotricuspid isthmus-dependent AFL, 4 (8%) with atrial scars-dependent AFL, and 8(16%) with both cavotricuspid isthmus and atrial scars-dependent AFL. Conclusion: RFCA was effective and safe for pediatric AFL. There is no difference on the acute success rate, the follow-up AFL recurrence rate, as well as occurrence of SSS between the groups with and without CHD. AFL patients with CHD included the cavotricuspid isthmus-dependent AFL, atrial scars-dependent AFL or both.

Use of adenosine to shorten the post ablation waiting period for cavotricuspid isthmus-dependent atrial flutter.

BACKGROUND: Dormant conduction unmasked by adenosine predicts clinical recurrences of cavotricuspid isthmus (CTI) dependent atrial flutter following catheter ablation. Conventional practice involves a waiting period of 20 to 30 minutes after achievement of a bidirectional line of block (BDB) to monitor for recovery of conduction. OBJECTIVE: Assess whether abolition of dormant conduction with adenosine immediately after CTI ablation and BDB can predict the lack of CTI conduction recovery during the following 30 minutes. METHODS: Consecutive patients undergoing catheter ablation for CTI-dependent atrial flutter were studied. Following the completion of CTI ablation and documentation of BDB, adenosine (≥12 mg IV) was administered immediately. In cases of dormant conduction, the CTI was ablated again until its abolition. After the achievement of BDB without dormant conduction, spontaneous CTI reconnection during the following 30 minutes and dormant conduction with adenosine at 30 minutes were evaluated. RESULTS: A CTI block was achieved in 171 patients. Nine patients (5.3%) had dormant conduction across the CTI immediately after ablation and BDB, and required further ablation. Two patients (1.2%) had subsequent spontaneous time-dependent reconnection within 30 minutes. Two other patients (1.2%) developed late dormant conduction with adenosine at 30 minutes. All 4 patients underwent further ablation. CONCLUSION: A negative adenosine challenge immediately after CTI ablation with bidirectional block, or after abolition of dormant conduction with further ablation, strongly predicted the absence of subsequent spontaneous reconnection within 30 minutes. Based on these results, the conventional waiting period is unnecessary in 97.6% patients without dormant conduction after CTI-dependent flutter ablation.

Respiratory Distress in an Infant: An Uncommon Cause for a Common Complaint.

BACKGROUND: Respiratory distress and tachycardia are common presenting complaints in infants and young children, and evaluation typically focuses on respiratory infections. Tachydysrhythmias causing heart failure are rare and can be difficult to diagnose in young children, but are reversible if recognized and treated early. CASE REPORT: We discuss a 7-week-old female infant who presented with respiratory distress and persistent tachycardia. Evaluation revealed severe cardiac dysfunction with an underlying atrial flutter discovered on electrocardiography after adenosine administration. Rate control by synchronized electrocardioversion resulted in resolution of symptoms and restoration of cardiac function, confirming the diagnosis of atrial flutter-induced cardiomyopathy. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Persistent or inappropriate tachycardia in a young child should not be dismissed and underlying dysrhythmia should be considered.

Quando indicar ablação para as principaisarritmias atriais e ventriculares? / When is ablation indicated for the principal atrial and ventricular arrhythmias?

Arritmias supraventriculares são distúrbios do ritmo comuns na prática clínica diária. As duas principais opções de tratamento são o medicamentoso, considerado de segunda linha devido à baixa eficácia, necessidade de uso por longa data, efeitos colaterais, interaçãomedicamentosa e potencial efeito proarrítmico; e o invasivo com ablação, atualmente o padrão ouro devido a baixa complicação e alta eficácia. As arritmias ventriculares são menos comuns, podendo estar associadas a prognóstico e risco de morte súbita cardíacadiferentes, de acordo com a presença ou não de alteração estrutural cardíaca. A ablação por cateter possui papel diferente no tratamento das arritmias ventriculares nestes dois grupos de pacientes. O objetivo desta revisão é avaliar o papel da ablação por cateter,resumindo as principais indicações deste procedimento no manuseio das arritmias supraventriculares e ventriculares...

Supraventricular arrhythmias are common rhythm disturbances in daily clinical practice. The two main treatment options are pharmacological, and catheter ablation. Pharmacologicaltreatment is considered the second line option due to its low efficacy, the need for long-term adherence, the risk of side effects, drug interactions, and potential proarrhythmic effects. Catheter ablation is currently the gold standard therapy, due to its low complications and high efficacy. Ventricular arrhythmias are less common, and may be associated with different prognoses and levels of risk of sudden cardiac death, depending on the presence or absence of structural heart disease. Catheter ablation has a different role in the treatment of ventricular arrhythmias in these two groups of patients. The objective ofthis review is to evaluate the role of catheter ablation, summarizing the main indications of this procedure in the management of supraventricular and ventricular arrhythmia...

No Benefit of Complex Fractionated Atrial Electrogram Ablation in Addition to Circumferential Pulmonary Vein Ablation and Linear Ablation: Benefit of Complex Ablation Study.

BACKGROUND: The optimal ablation strategy for persistent atrial fibrillation (AF) remains unclear. METHODS AND RESULTS: This multicentre randomized study compared circumferential pulmonary vein ablation+linear ablation (control arm) versus circumferential pulmonary vein ablation+linear ablation+complex fractionated atrial electrogram (CFAE) ablation (CFAE arm) in patients with persistent AF. Circumferential pulmonary vein ablation was performed followed by roof and mitral isthmus ablation, before CFAE ablation in the CFAE arm. Ablation strategy was maintained at the first redo procedure. Sixty-five patients were recruited in each arm. The mean age was 61±10 years, 75% were men, median AF duration was 2 years, 42% had long-lasting persistent AF, 68% had associated cardiovascular disease, mean left atrial dimension was 46±6 mm, and median CHA2DS2-VASc score was 2. Ablation and procedure times were significantly longer in the CFAE arm (70±20 versus 55±17; 201±35 versus 152±45 minutes; P<0.005). After a mean follow-up of 35±5 months, single-procedural success off antiarrhythmic drugs at 12 months (CFAE: 30/65 [46%] versus control: 37/65 [57%]; P=0.29) and multiprocedural success (CFAE: 51/65 [78%] versus control: 52/65 [80%]; P=1.0) were not significantly different. At the first redo procedure, patients in the CFAE arm had a higher incidence of organized atrial tachycardia/flutter (24/33 [73%] versus 11/31 [35%]; P=0.005) and gap-related macro-re-entrant flutter (8/33[24%] versus 1/31[3%]; P=0.03). Early recurrence of atrial arrhythmia was an independent predictor of late recurrence. CONCLUSIONS: CFAE ablation did not confer incremental benefit when performed in addition to circumferential pulmonary vein ablation and linear ablation. It was associated with a higher incidence of gap-related flutter. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01711047.