Cryoballoon Ablation for Paroxysmal Atrial Fibrillation in Septuagenarians: a Prospective Study

Aims

To evaluate the effects of pulmonary vein isolation (PVI) in terms of feasibility, safety and success rate on a midterm follow-up period in septuagenarians undergoing ablation with the Arctic Front Cryoballoon for atrial fibrillation (AF).

Methods and Results

We prospectively enrolled 21 patients aged 70 years or older (14 male; age 73 ± 2.5 years) elected to circumferential PVI with the 28mm cryoballoon for symptomatic drug resistant paroxysmal AF. A total number of 82 pulmonary veins (PV) were evidenced. Successful isolation could be obtained in all 82 (100%) PV ostia at the end of procedure. No major complication occurred during procedure. At a mean follow-up of 11.5 ± 4.7 months following ablation, 62% of patients did not present recurrence of atrial arrhythmias.

Conclusion

Cryoballoon ablation may be feasible and safe in older patients. Moreover a large proportion of the latter did not present AF recurrence during follow-up.     

Pharmacological treatment of short-coupled idiopathic ventricular fibrillation: A review

Short-coupled idiopathic ventricular fibrillation (IVF) is a subtype of IVF in which episodes of polymorphic ventricular tachycardia or ventricular fibrillation are initiated by short-coupled premature ventricular contractions (PVCs). Our understanding of the pathophysiology is evolving, with evidence suggesting that these malignant PVCs originate from the Purkinje system. In most cases, the genetic underpinning has not been identified. Whereas the implantation of an implantable cardioverter-defibrillator is uncontroversial, the choice of pharmacological treatment is the subject of discussion. In this review, we summarize the available knowledge on pharmacological therapy in short-coupled IVF and provide our recommendations for management of patients with this syndrome.     

Atrial Fibrillation and Beta Thalassemia Major: The Predictive Role of the 12-lead Electrocardiogram Analysis

Background

Paroxysmal atrial tachyarrhythmias frequently occur in beta-thalassemia major (β-TM) patients.The aim of our study was to investigate the role of maximum P-wave duration (P max) and dispersion (PD), calculated trough a new manually performed measurement with the use of computer software from all 12-ECG-leads,as predictors of atrial-fibrillation (AF) in β-TM patients with conserved systolic or diastolic cardiac function during a twelve-months follow-up.

Materials and Methods

50 β-TM-patients (age38.4±10.1; 38M) and 50-healthy subjects used as controls, matched for age and gender, were studied for the occurrence of atrial arrhythmias during a 1-year follow-up, through ECG-Holter-monitoring performed every three months. The β-TM-patients were divided into two groups according to number and complexity of premature-supraventricular-complexes at the Holter-Monitoring (Group1: <30/h and no repetitive forms, n:35; Group2: >30/h or couplets, or run of supraventricular tachycardia and AF, n:15).

Results

Compared to the healthy control-group, β-TM patients presented increased P-max (107.5± 21.2 vs 92.1±11ms, P=0.03) and PD-values (41.2±13 vs 25.1±5 ms,P=0.03). In the β-TM population, the Group2 showed a statistically significant increase in PD (42.8±8.6 vs 33.2±6.5ms, P<0.001) and P-max (118.1±8.7 vs 103.1±7.5ms, P<0.001) compared to the Group1. Seven β-TM patients who showed paroxysmal AF during this study had significantly increased P-max and PD than the other patients of the Group2. Moreover, P-max (OR:2.01; CI:1.12-3.59; P=0.01) and PD (OR=2.06;CI:1.17-3.64;P=0.01) demonstrated a statistically significant association with the occurrence of paroxysmal AF,P min was not associated with AF-risk (OR=0.99; CI:0.25-3.40; P=0.9) in β-TM-patients. A cut-off value of 111ms for P-max had a sensitivity of 80% and a specificity of 87%, a cut-off value of 35.5ms for PD had a sensitivity of 90% and a specificity of 85% in identifying β-TM patients at risk for AF.

Conclusion

Our results indicate that P-max and PD are useful electrocardiographic markers for identifying the β-TM-high-risk patients for AF onset, even when the cardiac function is conserved.     

Statins Do Not Reduce Atrial Fibrillation After Cardiac Valvular Surgery: A Single Centre Observational Study

Introduction

Statins may theoretically reduce postoperative atrial fibrillation (AF) in patients after cardiac valvular surgery due to preservation of endothelial function and anti-ischaemic, anti-inflammatory and anti-remodelling effects.

Methods

Two hundred seventy-two patients who underwent cardiac workup and subsequently cardiac valvular surgery without AF and concomitant coronary artery bypass grafting (CABG) at our hospital were selected. Preoperative drug use and postoperative AF were recorded. AF was defined as any episode of AF longer than 10 s. In addition, results from echocardiography and blood samples were retrieved.

Results

Baseline characteristics were as follows: mean age was 65 ± 11 years, 142 (52%) patients were male, 189 (70%) had undergone aortic valve surgery and the mean left ventricular ejection fraction was 57 ± 12%. Statins were used by 79 patients (29%). Statin users, more often, had a prior percutaneous coronary intervention (25% vs 9%, p < 0.001) or CABG (24% vs 4%, p < 0.001), diabetes mellitus (22% vs 5%, p < 0.001) and more often used β-blockers (51% vs 24%, p < 0.001). Patients in the non-statin group more often had surgery on more than one valve (10% vs 3%, p = 0.043) and had a higher cholesterol level (222 ± 48 vs 190 ± 43 mg/dl, p < 0.001). Postoperative AF occurred in 54% (43/79) of the patients with and in 55% (106/193) of the patients without statins (p = 0.941). There was also no difference in the timing of onset of AF or duration of hospital stay.

Conclusion

In this observational study, statin use was not associated with a reduced incidence of AF in patients after cardiac valvular surgery.     

Evaluation of the vascular protective effects of new oral anticoagulants in high-risk patients with atrial fibrillation (PREFER-AF): study protocol for a randomized controlled trial

BackgroundAtrial fibrillation (AF) is known to be associated with several pathophysiological mechanisms including endothelial dysfunction of the heart and arterial vessels. Recent evidence suggests that new oral anticoagulant (NOAC) treatment may improve endothelial function and the inflammatory process involved in atherosclerosis in AF patients. This study is designed to determine the efficacy of NOAC therapy in the prevention of endothelial dysfunction and the progression of atherosclerosis of AF subjects.Method/designAF patients with a CHA2DS2-VASc score >2 and no previous history of overt coronary disease, severe peripheral arterial disease (PAD) or major stroke will be registered and randomly assigned either to the NOAC group (dabigatran or rivaroxaban) or the warfarin group in this prospective, randomized, 2-year follow-up study. Reactive hyperemia peripheral arterial tonometry (RH-PAT) measurements reflecting endothelial function will be conducted using the Endo-PAT2000 device. Left and right carotid intima-media thickness (IMT) will be measured at baseline, 12 months, and 24 months. The primary endpoint is defined as change in Reactive Hyperemia Index (RHI) at 12 months. Secondary endpoints included changes in the right and left maximum IMT of the common carotid artery (CCA) and internal carotid artery (ICA), the mean IMT of the CCA and ICA at 24 months, and 24-month cardiovascular events including cardiac death, stroke, acute myocardial infarction (AMI), overall cause of death, withdrawal of drug, or bleeding events.DiscussionThis is the first study to evaluate the efficacy of NOAC therapy for the prevention of endothelial dysfunction and progression of atherosclerosis in AF subjects. These findings are expected to expand the knowledge of NOAC pleotropic action in AF patients.

Trial registration

ClinicalTrials.gov: {"type":"clinical-trial","attrs":{"text":"NCT02544932","term_id":"NCT02544932"}}NCT02544932, registered on 7 September 2015.     

Increased inpatient mortality in patients hospitalized for atrial fibrillation and atrial flutter with concomitant amyloidosis: Insight from National Inpatient Sample (NIS) 2016-2017

PurposeUsing National Inpatient Database (NIS), comparison of clinical outcomes for patients primarily admitted for atrial fibrillation/flutter with and without a secondary diagnosis of amyloidosis was done. Inpatient mortality was the primary outcome and hospital length of stay (LOS), mean total hospital charges, odds of undergoing cardiac ablation, pharmacologic cardioversion, having a secondary discharge diagnosis of heart block, cardiogenic shock and cardiac arrest were secondary outcomes.MethodsNIS database of 2016, 2017 was used for only adult hospitalizations with atrial fibrillation/flutter as principal diagnosis with and without amyloidosis as secondary diagnosis using ICD-10 codes. Multivariate logistic with linear regression analysis was used to adjust for confounders.Results932,054 hospitalizations were for adult patients with a principal discharge diagnosis of atrial fibrillation/flutter. 830 (0.09%) of these hospitalizations had amyloidosis.Atrial fibrillation/flutter hospitalizations with co-existing amyloidosis have higher inpatient mortality (4.22% vs 0.88%, AOR: 3.92, 95% CI 1.81–8.51, p = 0.001) and likelihood of having a secondary discharge diagnosis of cardiac arrest (2.40% vs 0.51%, AOR: 4.80, 95% CI 1.89–12.20, p = 0.001) compared to those without amyloidosis.ConclusionsHospitalizations of atrial fibrillation/flutter with co-existing amyloidosis have higher inpatient mortality and odds of having a secondary discharge diagnosis of cardiac arrest compared to those without amyloidosis. However, LOS, total hospital charges, likelihood of undergoing cardiac ablation, pharmacologic cardioversion, having a secondary discharge diagnosis of heart block and cardiogenic shock were similar between both groups.     

Polysomnography in AF patients without prior diagnosis of obstructive sleep apnea reveals significant sleep abnormality: A strong case for screening in all patients with atrial fibrillation?

BackgroundObstructive sleep apnea (OSA) and atrial fibrillation (AF) are known to often coexist together. However, whether all patients with AF should be screened for sleep abnormalities is not clear. No previous study has examined the association of asymptomatic OSA with AF.ObjectiveThis study sought to determine the prevalence of asymptomatic OSA in patients with persistent AF and whether asymptomatic OSA is an independent risk factor for atrial fibrillation.MethodPatients with persistent AF without a prior diagnosis of OSA and asymptomatic for sleep abnormalities were prospectively enrolled over 12 months. All patients underwent polysomnography after informed consent. Patients without AF or OSA who underwent polysomnography during the same period served as controls.ResultsA total of 97 patients were studied; 50 were in the case group (patients with persistent AF) and 47 were in the control group (patients in sinus rhythm). Asymptomatic OSA was diagnosed on polysomnography in 72% of patients in the AF group and 17% of the control population. Multivariable analysis of factors including diabetes, hypertension, coronary artery disease, hypothyroidism, prior MI, and asymptomatic OSA, suggested asymptomatic OSA as an independent factor associated with AF.ConclusionA significant proportion (72%) of patients with persistent AF have underlying asymptomatic OSA. Sleep abnormality thus has a strong association with AF even in patients who are asymptomatic for OSA. Screening for OSA may be advised for all patients with AF, as this may have significant implications for management.     

Clinical outcome of ablation for long-standing persistent atrial fibrillation with or without defragmentation

Objective

To assess the outcome and associated risks of atrial defragmentation for the treatment of long-standing persistent atrial fibrillation (LSP-AF).

Methods

Thirty-seven consecutive patients (60.4 ± 7.3 years; 28 male) suffering from LSP-AF who underwent pulmonary vein isolation (PVI) and linear ablation were compared. All patients were treated with the Stereotaxis magnetic navigation system (MNS). Two groups were distinguished: patients with (n = 20) and without (n = 17) defragmentation. The primary endpoint of the study was freedom of AF after 12 months. Secondary endpoints were AF termination, procedure time, fluoroscopy time and procedural complications. Complications were divided into two groups: major (infarction, stroke, major bleeding and tamponade) and minor (fever, pericarditis and inguinal haematoma).

Results

No difference was seen in freedom of AF between the defragmentation and the non-defragmentation group (56.2 % vs. 40.0 %, P = 0.344). Procedure times in the defragmentation group were longer; no differences in fluoroscopy times were observed. No major complications occurred. A higher number of minor complications occurred in the defragmentation group (45.0 % vs. 5.9 %, P = 0.009). Mean hospital stay was comparable (4.7 ± 2.2 vs. 3.4 ± 0.8 days, P = 0.06).

Conclusion

Our study suggests that complete defragmentation using MNS is associated with a higher number of minor complications and longer procedure times and thus compromises efficiency without improving efficacy.     

Cholinergic activity regulates the secretome of epicardial adipose tissue: Association with atrial fibrillation

Botulinum toxin injection on epicardial fat, which inhibits acetylcholine (ACh) release, reduced the presence of atrial fibrillation (AF) in patients after heart surgery. Thus, we wanted to study the profile of the released proteins of epicardial adipose tissue (EAT) under cholinergic activity (ACh treatment) and their value as AF predictors. Biopsies, explants, or primary cultures were obtained from the EAT of 85 patients that underwent open heart surgery. The quantification of muscarinic receptors (mAChR) by real-time polymerase chain reaction or western blot showed their expression in EAT. Moreover, mAChR Type 3 was upregulated after adipogenesis induction (p < 0.05). Cholinergic fibers in EAT were detected by vesicular ACh transporter levels and/or acetylcholinesterase activity. ACh treatment modified the released proteins by EAT, which were identified by nano-high-performance liquid chromatography and TripleTOF analysis. These differentially released proteins were involved in cell structure, inflammation, or detoxification. After testing the plasma levels of alpha-defensin 3 (inflammation-involved protein) of patients who underwent open heart surgery ( n = 24), we observed differential levels between the patients who developed or did not develop postsurgery AF (1.58 ± 1.61 ng/ml vs. 6.2 ± 5.6 ng/ml; p < 0.005). The cholinergic activity on EAT might suggest a new mechanism for studying the interplay among EAT, autonomic nervous system dysfunction, and AF.     

Concomitant epicardial left atrial appendage ligation and left atrial ablation of atrial fibrillation: Safety,feasibility and outcome

IntroductionWe present initial results of patients undergoing a combined procedure of epicardial LAA ligation in addition to left atrial ablation for AF.Methods9 patients were included for additional use of LARIAT as an individual treatment approach for AF. First an epicardial LAA ligation was performed, in the same procedure left atrial ablations consisting of PVI and additional substrate based modifying ablations were performed. Follow–up at 3 months and 12 months was performed.ResultsThere was only 1 minor procedural complication (11%) involving epicardial bleeding and 2 late adverse events of pericardial tamponade and stroke. At the final follow-up (median 20 months) 7 patients were in stable sinus rhythm (78%) and 2 pts had reduced AF burden.ConclusionConcomitant epicardial LAA ligation and ablation is feasible in selected patients with a reasonable risk profile. More prospective data are required to validate the safety and efficacy.     

Founder mutations in the Netherlands: familial idiopathic ventricular fibrillation and DPP6

In this part of a series on founder mutations in the Netherlands, we review familial idiopathic ventricular fibrillation linked to the DPP6 gene. Familial idiopathic ventricular fibrillation determines an intriguing subset of the inheritable arrhythmia syndromes as there is no recognisable phenotype during cardiological investigation other than ventricular arrhythmias highly associated with sudden cardiac death. Until recently, it was impossible to identify presymptomatic family members at risk for fatal events. We uncovered several genealogically linked families affected by numerous sudden cardiac deaths over the past centuries, attributed to familial idiopathic ventricular fibrillation. Notably, ventricular fibrillation in these families was provoked by very short coupled monomorphic extrasystoles. We were able to associate their phenotype of lethal arrhythmic events with a haplotype harbouring the DPP6 gene. While this gene has not earlier been related to cardiac arrhythmias, we are now able, for the first time, to identify and to offer timely treatment to presymptomatic family members at risk for future fatal events solely by genetic analysis. Therefore, when there is a familial history of unexplained sudden cardiac deaths, a link to the DPP6 gene may be explored as it may enable risk evaluation of the remaining family members. In addition, when closely coupled extrasystoles initiate ventricular fibrillation in the absence of other identifiable causes, a link to the DPP6 gene should be suspected.     

The changing face of glucagon fibrillation: structural polymorphism and conformational imprinting

We have established a time-resolved fluorescence assay to study fibrillation of the 29 residue peptide hormone glucagon under a variety of different conditions in a high-throughput format. Fibrils formed at pH 2.5 differ in fibrillation kinetics, morphology, thioflavin T staining and FTIR/CD spectra depending on salts, glucagon concentration and fibrillation temperature. Apparent fibrillar stability correlates with spectral and kinetic properties; generally, fibrils formed under conditions favourable for rapid fibrillation (ambient temperatures, high glucagon concentration or high salt concentration) appear less thermostable than those formed under more challenging conditions (high temperatures, low glucagon or low salt concentrations). Properties of preformed fibrils used for seeding are inherited in a prion-like manner. Thus, we conclude that the structure of fibrils formed by glucagon is not the result of the global energy minimization, but rather kinetically controlled by solvent conditions and seed-imprinting. Fibrillar polymorphism, which is being reported for an increasing number of proteins, probably reflects that fibrils have not been under evolutionary constraints to retain a single active conformation. Our results highlight the complexity of the fibrillation mechanism of glucagon, since even subtle changes in fibrillation conditions can alter the type of fibrils formed, or result in formation of mixtures of several types of fibrils.     

Atrial Fibrillation after Cardiac Surgery: Where are we now?

Objective

To review: 1) Pathophysiology of postoperative atrial fibrillation (POAF); 2) Risk factors for POAF; 3) Prophylaxis of POAF; 4) Treatment of POAF; and 5) Future directions.

Methods

We searched the Medline database for articles published between January, 1966 to September, 2008. We used the following keywords: Atrial fibrillation, Postoperative atrial fibrillation, Coronary Artery Bypass, and antiarrhythmic agents. Additionally, we searched references from all relevant articles.

Conclusions

POAF occurs in 25-60% of patients depending on the type of cardiac surgery performed. POAF generally occurs on postoperative day 2 or 3. POAF is associated with an increased risk of morbidity and mortality, and longer hospital stay. Prophylactic treatments reduce the likelihood of POAF. In patients who experience POAF, rhythm strategies should be used in those who are symptomatic and hemodynamically unstable. All other patients should be managed with rate strategies.     

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.     

4:2:1 conduction of an AF initiating trigger

A 44 year old male with idiopathic dilated cardiomyopathy was undergoing persistent atrial fibrillation (AF) ablation. Following antral ablation, AF terminated into a regular narrow complex rhythm. Earliest activation was mapped to a focus in the superior vena cava (SVC) which was conducted in a 2:1 ratio to the atria which in turn was conducted with 2:1 ratio to the ventricles, resulting in an unusual 4:2:1 conduction of the SVC tachycardia. 1:1 conduction of the SVC tachycardia to the atrium preceded initiation of AF. During AF, SVC tachycardia continued unperturbed. Sinus rhythm was restored following catheter ablation of the focus.     

Relationship of troponin to incident atrial fibrillation occurrence,recurrence after radiofrequency ablation and prognosis: a systematic review,meta-analysis and meta-regression

Objective: To explore the association between the levels of troponin (Tn) and incident atrial fibrillation (AF) occurrence, AF recurrence after radiofrequency ablation (RFA), and the risk trend of AF related prognosis (stroke, major bleeding and mortality).

Methods: Twenty-seven studies were included after a systematic search in PubMed from 2005 to 2017, including 13 associated with incident AF occurrence, 8 associated with AF recurrence after RFA and 6 studies evaluating the risk trend of AF-related prognosis with increased Tn levels.

Results: Compared with ‘no incident AF occurrence’ patients, the incident AF occurrence group had similar baseline troponin I (TnI) levels (standardized mean differences [SMD]?=?0.42, 95% CI: ?0.02–0.86, p?=?0.06; I²?=?87.0%, N?=?6), but higher troponin T (TnT) levels (SMD?=?3.77, 2.13–5.42, p?<0.001; I²=99.7%, N?=?8). AF recurrence patients had similar peri-ablation TnI levels, but higher peri-ablation TnT levels compared to the ‘no AF recurrence’ group with pooled SMD. (TnI: SMD: ?0.61, ?1.22to 0, p?=?0.049; I²?=?87.1%; TnT: 0.38, 0.14–0.62, p?=?0.002; I²?=?64.7%). On meta-regression, there was an increased risk trend for stroke/systemic embolism (SE) (r²?=?0.93, p?=?0.04) or major bleeding (r²?=?0.99, p?r²?=?0.09, p?=?0.25) or TnT (r²?=?0.20, p?=?0.31), and stroke/SE (r²?=?0.02, p?=?0.74) or major bleeding (r²?=?0.002, p?=?0.92) was non-significantly related to increasing TnI levels.

Conclusions: In our systematic review, meta-analysis and meta-regression, TnT was associated with both incident AF occurrence and AF recurrence after RFA, as well as stroke/SE and major bleeding. In contrast, TnI was not associated with incident AF occurrence, AF recurrence after RFA or prognosis (stroke/SE, major bleeding).     

Design,synthesis and evaluation of phenethylaminoheterocycles as Kv1.5 inhibitors

Phenethylaminoheterocycles have been prepared and assayed for inhibition of the K_v1.5 potassium ion channel as a potential approach to the treatment of atrial fibrillation. A diverse set of heterocycles were identified as potent K_v1.5 inhibitors and were advanced to pharmacodynamic evaluation based on selectivity and pharmacokinetic profile. Heterocycle optimization and template modification lead to the identification of compound 24 which demonstrated increased atrial effective refractory period in the rabbit pharmacodynamic model with mild effects on blood pressure and heart rate.     

Atrial fibrillation ablation: a single center comparison between remote magnetic navigation, cryoballoon and conventional manual pulmonary vein isolation

Background

The aim of the study was to compare in our center the effect of different ablation techniques on intermediate term freedom from atrial fibrillation (AF) or atrial tachycardia (AT) in patients affected by refractory AF.

Methods and Results

We retrospectively selected 94 patients who underwent AF ablation in our electrophysiological laboratory from June 2007 to December 2009. 29 patients underwent manual circumferential pulmonary vein isolation (mCPVI), 35 underwent remote magnetic navigation assisted CPVI (rmtCPVI) and 30 cryoballoon CPVI (cCPVI). Antiarrhythmic drugs were systematically stopped 2 months after the procedure (end of the "blanking period").At a mean follow-up of 12,64 ± 6,41 months (range 2-31), the success rate for mCPVI group was 65.5% (19 patients), 66.7 % (20 patients) for the rmtCPVI group and 65.7 % (23 patients) for the cCPVI group (p = 0.625). Procedural and fluoroscopy times were significantly reduced in the cCPVI group (both p < 0.001). Univariate Cox regression showed that no clinical variables were independently associated with recurrence.

Conclusions

In our center''s experience cCPVI and rmtCPVI have been demonstrated to be as effective as mCPVI. cCPVI seemed to be associated with lower procedural and fluoroscopy times.     

A linear ablating system in the left and right atrium: feasibility, catheter performance and clinical results

IntroductionWe describe the use of a ablating system to compartmentalise and regionally isolate the atria in paroxysmal and persistent atrial fibrillation (AF).Methods40 patients were studied, 25 paroxysmal AF and 14 persistent AF. One patient enrolled was later found to be in left atrial flutter and was excluded. The Cardima Revelation® TX catheter system with Intellitemp® Radiofrequency (RF) energy control device and a Medtronic Atakar® RF generator were used to place wide area circumferential ablations to achieve conduction block into the left and right sided pulmonary veins. Roof lines and mitral isthmus lines were also performed. In patients with persistent AF and in repeat procedures, right atrial compartmentalisation was performed with an anterior superior vena cava (SVC) to inferior vena cava (IVC) line and a septal SVC to IVC line.ResultsAt 6 months, 18 of the 39 patients were asymptomatic, 10 had improved symptoms and 22 were in sinus rhythm. In the paroxysmal group, 11 were asymptomatic, 7 had improved symptoms and 16 (64%) were in sinus rhythm. In the persistent group, 7 were asymptomatic, 3 had improved symptoms and 6 (43%) were in sinus rhythm. The total group AF burden was 37.8 ± 5.4 hrs pre-procedure and 23.1 ± 5.1 hrs at 6 months post procedure. Mean temperature, impedance and power recorded at each pole demonstrated effective power delivery at all poles. No catheter charring was observed, complication rates were comparable to standard AF ablation technique.ConclusionLinear ablation in the left and right atria to mimic Cox’s Maze is feasible and safe using this ablating system.