Drug-refractory Paroxysmal Atrial Fibrillation Research Articles

Ten-Year Clinical Outcome After Circumferential Pulmonary Vein Isolation Utilizing the Hamburg Approach in Patients With Symptomatic Drug-Refractory Paroxysmal Atrial Fibrillation.

Circumferential pulmonary vein isolation (CPVI) is increasingly performed for the treatment of symptomatic drug-refractory paroxysmal atrial fibrillation. Long-term data for >10 years after CPVI are sparse. We investigated the long-term clinical outcome and progression of paroxysmal atrial fibrillation after double-lasso and 3-dimensional electroanatomical mapping-guided CPVI. From 2003 to 2004, 161 patients (mean age: 60±10 years) with symptomatic drug-refractory paroxysmal atrial fibrillation were prospectively enrolled and underwent electroanatomical mapping-guided CPVI. Right-sided and left-sided continuous circular lesions encircling the ipsilateral pulmonary veins were placed with irrigated radiofrequency energy. The procedural end point was the absence of pulmonary vein spikes 30 minutes after CPVI verified by 2 spiral catheters placed within the ipsilateral pulmonary veins (double-lasso technique). Major periprocedural complications occurred in 5 of 161 patients (3.1%). Follow-up was based on outpatient clinic visits, including Holter-ECGs and telephonic interviews. After a single procedure and median follow-up of 129.0 months (interquartile range, 124.7-133.1 months), stable sinus rhythm was present in 53 of 161 (32.9%) patients. Multiprocedural outcome after a mean of 1.73±0.9 procedures and a median follow-up of 123.4 months (interquartile range, 61.0-131.0 months) resulted in stable sinus rhythm in 101 of 161 patients (62.7%). Progression toward persistent atrial fibrillation was observed in 10 of 161 patients (6.2%). Ten-year single-procedural outcome of CPVI in patients with paroxysmal atrial fibrillation resulted in stable sinus rhythm in 32.9% and in 62.7% of patients after multiple procedures. The progression rate to persistent AF was remarkably low.

Effect of remote ischemic preconditioning on left atrial remodeling and prothrombotic response after radiofrequency catheter ablation for atrial fibrillation

Radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) is known to induce left atrial remodeling and prothrombotic response. This study aimed to evaluate the effect of remote ischemic preconditioning (RIPC) on left atrial remodeling and prothrombotic response induced by RFCA of AF. Forty-four patients with drug-refractory paroxysmal AF undergoing RFCA were randomized into RIPC (four short episodes of forearm ischemia) and control groups before the procedure. Blood samples were collected before RIPC/sham RIPC, and 24 and 72hours later after the procedure. The atrial remodeling marker matrix metalloproteinase-9 (MMP-9) and endothelial damage marker von Willebrand factor (vWF) were measured using enzyme-linked immunosorbent assay. Plateletactivation was evaluated by flow cytometric measurements of the expression of platelet P-selectin (CD62P) and active glycoprotein IIb/IIIa receptor (PAC-1). The early recurrence of atrial fibrillation (ERAF) in the two groups was observed over the subsequent 3 months. RFCA resulted in a significant increase in MMP-9 and vWF in both the groups, which persisted for 72hours. However, the expression of CD62P and PAC-1 showed less increase during RFCA in either group. The RIPC group showed a lower increase in MMP-9 and vWF compared with the control group. In contrast, no significant differences were found in the trend of expression of CD62P and PAC-1 during RFCA between the two groups. The AF recurrence in the 3 months after the ablation was significantly lower in the RIPC group than in the control group. RIPC before RFCA for paroxysmal AF significantly reduces the increase in markers of left atrial remodeling and endothelial damage associated with the procedure, and results in a lower ERAF.

PP135 Cost-Effectiveness Of Cryoballoon Ablation In China: Real-World Results

Introduction:Paroxysmal atrial fibrillation (PAF) represents a significant economic burden to the healthcare system. Catheter ablation is a commonly adopted treatments for PAF, and cryoballoon ablation (CBA) has been recently proven to be as effective as radiofrequency ablation (RFA). This study aims to evaluate the cost-effectiveness of CBA versus RFA in patients with drug-refractory PAF in China.Methods:A Markov model was developed to study the effects and the costs of CBA versus RFA. Cost and probability inputs data were obtained mainly from a real-world study of 85 CBA and 284 RFA patients treated in a tertiary hospital between July 2014 and July 2016. Propensity score matching was used to overcome retrospective bias, resulting in including 75 patients in each group. Input data gaps were closed with literature review and advisory board. A simulation was carried out for 14 cycles/years, and a discount rate of 3 percent was used. Then, a probabilistic sensitivity analysis was carried out with Monte Carlo approach.Results:In the base case scenario, the cumulative costs incurred by the CBA and RFA groups were CNY 132,222 (USD 20,767) and CNY 147,304 (USD 23,136), respectively. Over the 14-year period, the quality-adjusted life years (QALYs) gained by the CBA group was 7.85 versus 7.71 in the RFA group. The incremental cost-effectiveness ratio for CBA versus RFA was thus CNY 107,729 (USD 16,920)/QALY. Model results were most sensitive to the cost incurred during the first hospitalization, recurrence rate, and relative utility weights. The probability of CBA being cost-effective for willingness to pay thresholds of per capita GDP in China was estimated to be 99 percent.Conclusions:Compared with RFA, CBA is a cost-saving treatment providing increased QALYs. It represents good value for money for patients with drug-refractory PAF in China. However, further evidence needs to be generated from larger-scale studies in China.

Paroxysmal Atrial Fibrillation Catheter Ablation Outcome Depends on Pulmonary Veins Anatomy.

BackgroundPulmonary veins (PV) are often the trigger to atrial fibrillation (AF). Occasionally, left PVs converge on a common trunk (LCT) providing a simpler structure for catheter ablation.ObjectiveTo compare the clinical characteristics and outcomes of ablation in paroxysmal atrial fibrillation (PAF) of patients with or without LCT.MethodsCase-control study of patients undergoing first-ever catheter ablation procedure for drug refractory PAF. The information was taken from patients' records by means of a digital collection instrument, and indexed to an online database (Syscardio(r)). Clinical characteristics and procedures were compared between patients with or without LCT (LCT x n-LCT), adopting a level of statistical significance of 5%. The primary endpoint associated with efficacy was lack of atrial arrhythmia over the follow-up time.ResultsOne hundred and seventy two patients with PAF were included in the study, 30 (17%) LCT and 142 (83%) n-LCT. The clinical characteristics, comorbidities, symptoms scale and risk scores did not differ between the groups. There was AF recurrence in 27% of PAF patients in the n-LCT group and only 10% of patients in the LCT group (OR: 3.4 p: 0.04) after a follow-up of 34 ± 17 months and 26 ± 15 months respectively.ConclusionPatients with a LCT have a significantly lower recurrence rate when compared to patients without this structure. It is mandatory to report the results of AF catheter ablation as a PV anatomical variation function.

Five-year clinical outcomes of visually guided laser balloon pulmonary vein isolation for the treatment of paroxysmal atrial fibrillation.

Visually guided laser balloon (VGLB) ablation allows for pulmonary vein isolation (PVI) under direct endoscopic control. Short- and midterm clinical outcomes are in accordance with results of radiofrequency current (RFC) ablation for the treatment of paroxysmal atrial fibrillation (PAF). The current study sought to assess the long-term clinical outcomes of VGLB-based PVI for PAF. A total of 90 patients [60 ± 10 years; 33 (37%) female, left atrial diameter 42 ± 4mm] with drug-refractory PAF underwent VGLB ablation. The median duration of PAF until VGLB ablation was 36 (interquartile range 12; 84) months. Follow-up was based on outpatient clinic visits including Holter ECGs and telephone interviews. Repeat ablation due to arrhythmia recurrences was performed using RFC ablation. After a single VGLB procedure, 5-year freedom from arrhythmia recurrence was 51% [95% confidence interval (CI) 39-62%]. Thirty-three patients underwent repeat RFC ablation procedures, resulting in multiple procedure freedom from arrhythmia recurrence of 78% (95% CI 68-88%). Major periprocedural complications occurred in four patients (4%). VGLB ablation for the treatment of drug-refractory PAF is safe and results in 5-year single and multiple procedure arrhythmia-free survival of 51 and 78%, respectively.

Value of two left atrium and pulmonary vein stereoscopic imaging reconstruction methods on guiding radiofrequency ablation for atrial fibrillation

Objective: To compare the value of two 3D imaging reconstruction methods for left atria and pulmonary vein on guiding the catheter ablation for atrial fibrillation (AF). Methods: From January 2014 to January 2017, a total of 100 drug refractory paroxysmal AF patients were divided into left atria direct angiography group (n=50), and indirect angiography group (n=50). 3D CARTO system was applied for mapping and guiding the ablation procedure. Patients assigned to direct angiography group were treated as follows: intraoperative puncture of atrial septum, inject contrast agent directly into the left atrium, conduct left atrial and pulmonary venous rotation angiography, reconstruct three-dimensional image, integrate the image into real-time X-ray system to facilitate circumferential pulmonary vein isolation. Patients assigned into the indirect angiography group were treated as follows: inject contrast agent through the right ventricle, conduct delayed rotation angiography of the left atria and pulmonary vein to guide circumferential pulmonary vein fixation and ablation. The left atrial and pulmonary venous image acquisition, the operation and X-ray exposure time, the success rate and the incidence of complication of the two groups were compared. The patients were followed up for 3-6 months. Results: General clinical characteristics of the two groups were similar(all P>0.05). Ablation was successful in all 100 patients. The operation time[(112.0±21.4)min vs. (134.0±24.3)min]and X-ray exposure time((10.7±4.7)min vs. (15.8±5.2)min)were significantly lower in direct angiography group than in indirect angiography group (both P<0.01). There was no significant difference between the two groups in the immediate (86%(43/50) vs. 82%(41/50), P=0.59) and short-term (76%(38/50) vs. 72%(36/50), P=0.65) success rate and complication rate (1 aneurysm in the direct angiography group, 1 pericardial tamponade in the indirect angiography group). In-hospital mortality was zero percent. Conclusion: It is safe and effective method to guide the radiofrequency catheter ablation of paroxysmal atrial fibrillation by reconstruction 3D image of left atrium and pulmonary vein. Compared with indirect angiography group, direct angiography group can improve the imaging quality of left atrium and pulmonary vein, decrease the X-ray exposure time of the ablation procedure.

GW28-e1070 Non–Pulmonary Vein Foci in Paroxysmal Atrial Fibrillation: Prevalence, Mechanisms, Induction and Ablation

Studies have demonstrated that pulmonary vein (PV) is the major source of ectopic foci initiating paroxysmal atrial fibrillation (PAF). Pulmonary vein isolation (PVI) is recognized to be the cornerstone of radiofrequency catheter ablation for drug-refractory PAF. However, with broadening of

Using anatomical landmark to avoid phrenic nerve injury during balloon-based procedures in atrial fibrillation patients.

Atrial fibrillation (AF) is an arrhythmia which affects as many as 2.7 million Americans. AF should be treated, because it can lead to a four-to-fivefold increased risk of experiencing a stroke. The American College of Cardiology/American Heart Association guidelines for the treatment of drug refractory and symptomatic paroxysmal AF denote catheter ablation as the standard of care. The newest ablation treatment, cryoballoon, uses a cold balloon tip. The biggest risk factor associated with the cryoballoon ablation is phrenic nerve injury (PNI). The purpose of this study is to measure relevant distances from specific landmarks to the right phrenic nerve (RPN) to create a safe zone for physicians. Using 30 cadaveric specimens, we measured laterally from the right superior pulmonary vein orifice (RSPV) to the RPN at the level of the sixth thoracic vertebra and laterally from the lateral border of the sixth thoracic vertebral body (T6) to the RPN. The depth and width of the left atrium (LA) were also measured to establish a cross-sectional area of the LA. The cross-sectional area of the LA was then correlated with the averaged measurements to see if the area of the LA could be a predictor of the location of the RPN. The average distance from the RPN-RSPV was 9.6mm (range 4.3-18.8mm). The average RPN-T6 distance was 30.6mm (range 13.7-49.9mm). There was a non-significant trend that suggests as the size of the LA increases, the measured distances also increased. Using the lateral border of the sixth thoracic vertebra as a landmark, which can be viewed under fluoroscopy during the procedure, physicians can triangulate the distance to the RSPV and determine the approximate position of the RPN. Furthermore, physicians can perform a preoperative echocardiogram to determine the size of the LA to assist in determining the position of the RPN with the hopes of avoiding injury to the RPN.

The relationship between high-sensitivity C-reactive protein (hsCRP) levels and atrial fibrillation early recurrence after paroxysmal atrial fibrillation radiofrequency catheter ablation

To prospectively clarify the predictive value of high-sensitivity C-reactive protein (hsCRP) on the risk for recurrent atrial arrhythmia in paroxysmal atrial fibrillation (PAF) population who accepted radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). There were 57 consecutive patients (53.32±9.98 years; 42 males) with drug-refractory PAF who underwent RFCA were included. Plasma levels of hsCRP and high-sensitivity cardiac troponin T (hs-cTnT) were measured on admission and first five days after RFCA. Twenty-five patients (43.86%) had early recurrence of atrial fibrillation (ERAF). Compared to patients without ERAF (no-AF-recurrence group), baseline hsCRP levels had no significant difference in patients with ERAF (AF recurrence group). There were no significant differences in the peak hsCRP and hs-cTnT levels between no-AF-recurrence group and AF recurrence group. However, change of hsCRP level was significantly correlated with change in hs-cTnT level in patients undergoing RFCA (r=0.268, P=0.044). Among those AF patients undergoing ablation, change of hsCRP level could be for the myocardial injury related to RFCA procedure, which may not be a risk factor to predict ERAF. The variety of hsCRP level may be related to the degree of myocardial injury induced by RFCA.

805Ten-year clinical outcome after circumferential pulmonary vein isolation utilizing the Hamburg approach in patients with symptomatic drug-refractory paroxysmal atrial fibrillation

805Ten-year clinical outcome after circumferential pulmonary vein isolation utilizing the Hamburg approach in patients with symptomatic drug-refractory paroxysmal atrial fibrillation

Cryoballoon vs. open irrigated radiofrequency ablation for paroxysmal atrial fibrillation: long-term FreezeAF outcomes

BackgroundEffective treatment of paroxysmal atrial fibrillation (AF) is essential for reducing the risk of stroke and heart failure. Cryoballoon (CB) ablation has been developed as an alternative to the use of radiofrequency (RF) energy for electrical isolation of the pulmonary veins. Herein, we provide long-term data regarding the efficacy of CB ablation in comparison to RF.MethodsFreezeAF was a randomised non-inferiority study comparing CB ablation with RF ablation for the treatment of patients with drug-refractory paroxysmal AF. Procedural success for the long-term follow-up (30 months) was defined as freedom from AF with an absence of persistent complications.ResultsOf the 315 patients that were randomised and received catheter ablation, 292 (92.7%) completed the 30-month follow-up (147 in the RF group and 145 in the CB group). The baseline characteristics of the RF and CB groups were similar. Single-procedure success was achieved by 40% of patients in the RF group and 42% of the CB group (p < 0.001 for non-inferiority). When including re-do procedures in the analysis, the multiple procedure success rate was 72% in the RF group and 76% in the CB group.ConclusionThe data provide long-term evidence that CB ablation is non-inferior to RF ablation, with high proportions of patients reporting freedom from AF 30 months after the index procedure.Trial registrationClinicalTrials.gov Identifier: NCT00774566; first registered October 16, 2008; first patient included October 20, 2008.

Arrhythmogenic left atrial roof vein

A seventy year-old male was referred to our hospital to undergo radiofrequency catheter ablation (RFCA) for drug-refractory paroxysmal atrial fibrillation (AF). Pre-operative three-dimensional computed tomography revealed a unique left atrial (LA) roof vein. Electrophysiological findings showed expansion of the myocardial sleeve and local firing in the LA roof vein. We performed isolation of this arrhythmogenic abnormal vein concomitant with general pulmonary vein isolation in this case, and AF did not recur after the procedure.

Catheter ablation of paroxysmal atrial fibrillation: circumferential pulmonary vein ablation: success rates with and without exclusion of areas adjacent to the esophagus.

Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory paroxysmal atrial fibrillation. Circumferential pulmonary vein ablation is still the standard approach in these patients. The occurrence of an atrioesophageal fistula is a rare but life-threatening complication after such ablation procedures. This is due to the fact that the esophagus does frequently have a very close anatomical relationship to the left or right pulmonary vein ostia. The aim of our study was to evaluate whether the exclusion of areas adjacent to the esophagus does have a significant effect on the success rate after circumferential pulmonary vein ablation. Two hundred consecutive patients [121 men, 69 women; mean age 59.1years (SD±11.3years)] with symptomatic paroxysmal atrial fibrillation underwent a circumferential pulmonary vein ablation procedure (using the CARTO- or the NAVX-system). In 100 patients, a complete circumferential pulmonary vein ablation was attempted regardless of the anatomical relationship between the ablation sites and the esophagus (group A). In the remaining 100 patients, the esophagus was marked by a special EP catheter and areas adjacent to the esophagus were excluded from the ablation procedure. After discharge, patients were scheduled for repeated visits at the arrhythmia clinic at 1, 3, 6, 9, 12, 24 and 36months after the ablation procedure. The ablation procedure could be performed as planned in all 200 patients. In group A, all pulmonary veins could be isolated successfully in 88 out of 100 patients (88%). A mean number of 3.9 pulmonary veins (SD±0.37PVs) were isolated per patient. The 12 cases of an incomplete pulmonary vein isolation were due to poorly accessible pulmonary vein ostia. In group B, all pulmonary veins could be isolated successfully in only 58 out of 100 patients (58%; P<0.01). A mean number of 3.5PVs (SD±0.6PVs) were isolated per patient (P<0.01). This was mostly due to a close anatomical relationship to the esophagus. The ablation strategy had to be modified in 46/100 patients in group B because of a close anatomical relationship between the right (n=25) or left (n=21) pulmonary vein ostia and the esophagus. One year after the ablation procedure, 87% of patients in group A (87/100) and 79% of patients in group B (79/100) were free from an arrhythmia recurrence (P=0.19). Three years after catheter ablation, the success rate was 80% (no arrhythmia recurrence in 80 out of 100 patients) in group A and 66% in group B (no arrhythmia recurrence in 66 out of 100 patients; P=0.04). There were no major complications during long-term follow-up. The exclusion of areas adjacent to the esophagus results in a markedly higher percentage of incompletely isolated pulmonary veins after circumferential pulmonary vein ablation procedures. This results in a significantly higher arrhythmia recurrence rate during long-term follow-up.

First insights into cryoballoon-based pulmonary vein isolation taking the individual time-to-isolation into account.

Cryoballoon (CB)-based pulmonary vein isolation (PVI) is an established treatment for symptomatic atrial fibrillation (AF). In the present study, we sought to assess the efficacy and safety of CB-based PVI taking the individual time-to-isolation (TTI) into account. Sixty consecutive patients with drug-refractory paroxysmal atrial fibrillation [n = 49 (82%)] or short-standing persistent atrial fibrillation [n = 11 (18%)] underwent ablation with a 28-mm second-generation CB. The TTI was assessed by spiral mapping-catheter recordings and subsequently followed by an additional freeze-time of 120 s. No bonus freeze-cycle was applied. If the TTI could not be assessed, a fixed freeze-cycle duration of 240 s was applied and successful PVI confirmed thereafter. Clinical follow-up (FU) included 12-lead ECGs and 24 h Holter-ECGs at 3, 6, and 12 months. A blanking period of 3 months was defined. A total of 239 pulmonary veins (PVs) were identified and successfully isolated. The mean TTI assessed in 170/239 (71%) PVs was 52 ± 32 s. The mean number of CB applications was 1.2 ± 0.5; mean freeze-cycle duration was 192 ± 41 s. Mean procedure and fluoroscopy times were 80 ± 24 min and 16 ± 7 min, respectively. Transient phrenic nerve palsy occurred in one patient (2%). During a mean FU of 405 ± 67 days, 43 patients (72%) remained in stable sinus rhythm. Integrating an individual TTI protocol to CB-based PVI results in shorter freeze-cycle applications in a substantial portion of targeted PVs and an arrhythmia-free survival comparable to conventional ablation protocols. The complication rate is low.

HotBalloon Ablation of the Pulmonary Veins for Paroxysmal AF: A Multicenter Randomized Trial in Japan

BackgroundPoint-by-point catheter ablation is an established treatment for drug-refractory paroxysmal atrial fibrillation (PAF). However, it is time consuming, requires excellent technique to achieve complete pulmonary vein (PV) isolation, and is associated with severe complications. ObjectivesThe purpose of this study was to evaluate the safety and effectiveness of a HotBalloon ablation (HBA) compared with antiarrhythmic drug therapy (ADT) for the treatment of PAF. MethodsA prospective multicenter randomized controlled study was conducted in Japan. Patients with symptomatic PAF refractory to antiarrhythmic drugs (Class I to IV) were randomized to HBA or ADT at a 2:1 ratio and assessed for effectiveness in a comparable 9-month follow-up period. ResultsA total of 100 patients in the HBA group and 43 patients in the ADT group received treatment at 17 sites. HBA procedure produced acute complete PV isolation in 98.0% (392 of 400) of the PVs and in 93.0% (93 of 100) of patients in the HBA group. The chronic success rates after the 9-month effective evaluation period were 59.0% in the HBA group (n = 100) and 4.7% in the ADT group (n = 43; p < 0.001). The incidence of major complications was 11.2% (15 of 134 patients). The incidences of PV stenosis (>70%) and transient phrenic nerve injury were 5.2% and 3.7%, respectively. The mean fluoroscopy time was 49.4 ± 26.6 min (n = 134), and the mean procedure duration was 113.9 ± 31.9 min (n = 133). ConclusionsThis study demonstrates the superiority of HBA compared with ADT for treatment of patients with PAF, and a favorable safety profile.

Cryoballoon vs. radiofrequency ablation for paroxysmal atrial fibrillation: an updated meta-analysis of randomized and observational studies

Radiofrequency (RF) ablation represents a standard of care for pulmonary vein isolation in patients with drug-refractory paroxysmal atrial fibrillation (AF). In this setting, cryoballoon (CB) ablation has emerged as alternative therapy. However, the efficacy and safety of CB vs. RF ablation in patients with paroxysmal AF remain a matter of debate. We searched electronic scientific databases for studies of CB vs. RF ablation in patients with paroxysmal AF. Aggregate data were pooled to perform a meta-analysis. The primary efficacy and safety outcomes were the recurrence of any atrial arrhythmia and procedure-related complications, respectively. A total of 6473 participants from 10 studies (CB, n = 2232 vs. RF, n = 4241) were studied. After a median follow-up of 16 months, the risk of any atrial arrhythmia recurrence (risk ratio, RR 95% confidence interval [95% CI] = 1.01 [0.90-1.14], P = 0.83) and procedure-related complications (RR [95% CI] = 0.92 [0.66-1.28], P = 0.61) were comparable between CB vs. RF ablation. Cryoballoon ablation led to a higher risk of persistent phrenic nerve palsy (RR [95% CI] = 13.60 [3.87-47.81], P < 0.01) and a lower risk of cardiac tamponade (RR [95% CI] = 0.48 [0.25-0.89], P = 0.02) compared with RF ablation. There was a trend of statistically significant interaction between the type of CB and the duration of ablation (P for interaction = 0.09). In patients with paroxysmal AF, ablation therapy with CB is associated with efficacy and safety comparable to that of RF. Second-generation CB catheters seem to reduce procedure duration. Further studies are warranted to disclose the impact of second-generation CB catheters compared with RF for ablation of paroxysmal AF.

Are Some Anticoagulants More Equal Than Others? - Evaluating the Role of Novel Oral Anticoagulants in AF Ablation.

Left atrial ablation strategies are being increasingly performed as a Class 1 therapeutic indication for drug refractory paroxysmal atrial fibrillation (AF). Traditionally AF ablation has been performed with patients on uninterrupted warfarin therapy, however over the last few years, novel oral anticoagulants (NOACs) have emerged as attractive alternatives to warfarin in order to reduce stroke risk due to AF. NOACs are therefore increasingly being used instead of warfarin in the management of AF. There is also mounting evidence mainly in the form of small randomised studies and meta-analysis that have demonstrated that the use of NOACs for AF ablation is efficacious, safe and convenient. However the peri-procedural dosing protocols used in various studies especially in terms of whether NOAC use is interrupted or uninterrupted during AF ablation, have significant inter-operator and inter-institution variability. Currently there is also a lack of randomised controlled trials to validate the data obtained from meta-analyses. There is also evidence that use of NOACs may increase the requirement of unfractionated heparin during the procedure. This review article shall examine the currently available evidence-base, appraise the gaps in the current evidence and also underscore the need for larger randomised clinical trials in this rapidly developing field.

Incidence of asymptomatic oesophageal lesions after atrial fibrillation ablation using an oesophageal temperature probe with insulated thermocouples: a comparative controlled study.

Oesophageal probes to monitor luminal oesophageal temperature (LET) during atrial fibrillation (AF) catheter ablation have been proposed, but their effects remain unclear. Aim of this study is to evaluate the effects of an oesophageal temperature probe with insulated thermocouples. Patients with symptomatic, drug-refractory paroxysmal or persistent AF who underwent left atrial radiofrequency (RF) catheter ablation were prospectively enrolled. Patients were ablated using a single-tip RF contact force ablation catheter. An intraluminal oesophageal temperature probe was used in Group 1. In Group 2, patients were ablated without LET monitoring. Assessment of asymptomatic endoscopically detected oesophageal lesions (EDEL) was performed by oesophagogastroduodenoscopy (EGD) in all patients. Eighty patients (mean age 63.7 ± 10.7 years; men 56%) with symptomatic, drug-refractory paroxysmal (n = 28; 35%) or persistent AF were included. Group 1 and Group 2 patients (n = 40 in each group) were comparable in regard to baseline characteristics, but RF duration on the posterior wall was significantly shorter in Group 1 patients. Overall, seven patients (8.8%) developed EDEL (four ulcerations, three erythema). The incidence of EDEL in Group 1 and Group 2 patients was comparable (7.5 vs. 10%, P = 1.0). No major adverse events were reported in both groups. According to these preliminary results, the use of oesophageal temperature probes with insulated thermocouples seems to be feasible in patients undergoing AF RF catheter ablation. The incidence of post-procedural EDEL when using a cut-off of 39°C is comparable to the incidence of EDEL without using a temperature probe.

Effect of remote ischemic preconditioning on myocardial injury and inflammatory response induced by ablation for atrial fibrillation: A randomized controlled trial

BackgroundRemote ischemic preconditioning (RIPC) has been suggested to reduce postoperative release of cardiac and inflammatory markers in patients undergoing cardiac surgery. This study aimed to evaluate the effect of RIPC on nonischemic myocardial damage and inflammatory response in patients undergoing radiofrequency catheter ablation for paroxysmal atrial fibrillation (AF). MethodsSeventy-two patients with drug-refractory paroxysmal AF undergoing radiofrequency catheter ablation were randomized into RIPC or control groups. RIPC (intermittent arm ischemia through four cycles of 5-min inflation and 5-min deflation of a blood-pressure cuff) was performed once daily on 2 consecutive days before the ablation and immediately before ablation. Cardiac troponin-I (cTnI), high-sensitive C-reactive protein (hs-CRP), and interleukin (IL)-6 levels were measured before RIPC/sham RIPC, after the ablation, and 24 and 72h later. The early recurrence of atrial fibrillation (ERAF) in the two groups was observed over the subsequent 3months. ResultsRadiofrequency ablation resulted in a significant rise in cTnI, hs-CRP, and IL-6 in both groups, which persisted for 72h. The RIPC group showed a lower increase in cTnI (P<0.001), hs-CRP (P=0.003), and IL-6 (P=0.008) than the control and tended to have a lower risk of ERAF (hazard ratio [HR]=0.77, 95% confidence interval [CI]: 0.32–1.88). ConclusionsThese results show that RIPC before ablation for paroxysmal AF significantly reduces the increase in cTnI, hs-CRP, and IL-6 associated with the procedure and results in a lower risk of ERAF. These findings suggest that RIPC could provide cardioprotection against nonischemic myocardial damage.

Cryoballoon or Radiofrequency Ablation for Paroxysmal Atrial Fibrillation

BackgroundCurrent guidelines recommend pulmonary-vein isolation by means of catheter ablation as treatment for drug-refractory paroxysmal atrial fibrillation. Radiofrequency ablation is the most common method, and cryoballoon ablation is the second most frequently used technology.MethodsWe conducted a multicenter, randomized trial to determine whether cryoballoon ablation was noninferior to radiofrequency ablation in symptomatic patients with drug-refractory paroxysmal atrial fibrillation. The primary efficacy end point in a time-to-event analysis was the first documented clinical failure (recurrence of atrial fibrillation, occurrence of atrial flutter or atrial tachycardia, use of antiarrhythmic drugs, or repeat ablation) following a 90-day period after the index ablation. The noninferiority margin was prespecified as a hazard ratio of 1.43. The primary safety end point was a composite of death, cerebrovascular events, or serious treatment-related adverse events.ResultsA total of 762 patients underwent randomization (378 assigned to cryoballoon ablation and 384 assigned to radiofrequency ablation). The mean duration of follow-up was 1.5 years. The primary efficacy end point occurred in 138 patients in the cryoballoon group and in 143 in the radiofrequency group (1-year Kaplan–Meier event rate estimates, 34.6% and 35.9%, respectively; hazard ratio, 0.96; 95% confidence interval [CI], 0.76 to 1.22; P<0.001 for noninferiority). The primary safety end point occurred in 40 patients in the cryoballoon group and in 51 patients in the radiofrequency group (1-year Kaplan–Meier event rate estimates, 10.2% and 12.8%, respectively; hazard ratio, 0.78; 95% CI, 0.52 to 1.18; P=0.24).ConclusionsIn this randomized trial, cryoballoon ablation was noninferior to radiofrequency ablation with respect to efficacy for the treatment of patients with drug-refractory paroxysmal atrial fibrillation, and there was no significant difference between the two methods with regard to overall safety. (Funded by Medtronic; FIRE AND ICE ClinicalTrials.gov number, NCT01490814.)