Paroxysmal Atrial Fibrillation Ablation Research Articles

A novel treatment for esophageal lesions following atrial fibrillation ablation.

This study presents a novel technique for the treatment of a deep esophageal ulcer after ablation of paroxysmal atrial fibrillation (AF). Pulmonary vein isolation was performed using a radiofrequency irrigated tip catheter. On Day 5 of follow-up, a deep esophageal ulcer was observed. No significant visual improvement was observed after conventional treatment. Endoscopic negative pressure therapy in the esophagus was then applied for 5 days. A significant decrease in diameter and depth of the lesion was observed, possibly preventing perforation. Endoscopic negative pressure therapy can be used to heal thermal lesions after AF ablation procedures.

Combined ablation for paroxysmal atrial fibrillation and drug-refractory hypertrophic obstructive cardiomyopathy: a case report.

BackgroundHypertrophic obstructive cardiomyopathy (HOCM) is sometimes concomitant with atrial fibrillation (AF) and exacerbates heart failure symptoms. Although optimal medication for the reduction of left ventricular outflow tract (LVOT) obstruction and the maintenance of sinus rhythm should be considered, it is difficult to control the symptoms permanently.Case summaryA 45-year-old man, diagnosed with HOCM, presented with progressive dyspnoea on exertion, which significantly deteriorated during episodes of paroxysmal AF, despite optimal medical therapy. On echocardiography, we found LVOT obstruction with a peak pressure gradient of 98 mmHg, concomitant with redundant mitral valve leaflets, which caused significant systolic anterior motion (SAM). Since he declined open surgery, we selected a combination of catheter interventions, AF ablation, and alcohol septal ablation (ASA). After the AF ablation, the occurrence of AF significantly decreased, and there was no recurrence after the ASA. By 6 months, the plasma N-terminal pro-B-type natriuretic peptide level had decreased from 1022 to 124 pg/mL, the peak pressure gradient of LVOT decreased from 98 to 12 mmHg, and the left atrium volume decreased from 203 to 178.4 mL. The improvement in the SAM was visualized on echocardiography and was haemodynamically corroborated by the four-dimensional (4D)-flow cardiac magnetic resonance (CMR).DiscussionThe treatment of drug-refractory HOCM concomitant with paroxysmal AF needs both septal reduction and the maintenance of sinus rhythm, which can be accomplished through transcatheter interventions. Moreover, the detailed intra-ventricular haemodynamic assessment in HOCM patients can be explored using the 4D-flow CMR.

Lesion Sequence and Catheter Spatial Stability Affect Lesion Quality Markers in Atrial Fibrillation Ablation.

This study sought to analyze high-frequency catheter excursion in relation to lesion quality markers in 20 consecutive patients undergoing first-time radiofrequency (RF) ablation for paroxysmal atrial fibrillation (AF). Ablation therapy for AF requires the delivery of durable lesions. The extent to which lesion sequence, catheter spatial stability, and anatomic location influence lesion formation during RF ablation of AF is not well understood. Three-dimensional spatial excursion of the ablation catheter sampled at 60Hz during pre-specified pairs of RF lesions was extracted from the CARTO3 System (Biosense Webster Inc., Irvine, California) and analyzed by using custom-developed MATLAB software (MathWorks, Natick, Massachusetts) to define precise catheter spatial stability during RF ablation. Ablation parameters including bipolar electrogram amplitude reduction, impedance decline and transmurality-associated unipolar electrogram (TUE) as evidence of lesion transmurality during lesion placement were recorded and analyzed. We collected 437,760 position data points during lesion placement. Ablation catheter spatial stability and lesion formation parameters varied considerably by anatomic location. Lesions placed immediately had similar bipolar electrogram amplitude reduction, smaller impedance decline, but higher likelihood of achieving TUE compared to delayed lesions. Greater catheter spatial stability correlated with lesser impedance decline. Lesion sequence, ablation catheter spatial stability, and anatomic location are important modifiers of RF lesion formation. Lesions placed immediately are more likely to exhibit TUE. Greater ablation catheter stability is associated with lesser impedance decline but greater likelihood of TUE.

No antiarrhythmic effect of direct oral anticoagulants versus vitamin K antagonists in paroxysmal atrial fibrillation patients undergoing catheter ablation

IntroductionDirect oral anticoagulants (DOACs) are superior to vitamin K antagonists (VKAs) for the prevention of stroke in atrial fibrillation (AF) patients with elevated stroke risk. Possible antiarrhythmic effects of DOACs have been discussed. We analyzed impact of DOAC treatment on recurrence-free survival after AF catheter ablation. MethodsTwo-hundred and thirty-nine consecutive patients (median age 57 [IQR 48–64] years, 26.4% female) undergoing ablation for paroxysmal AF were included into this study. 68.6% of them received DOACs (DOAC group), 31.4% VKA (VKA group). The primary outcome was arrhythmia-free one-year survival. ResultsDOAC patients had lower BMI, shorter history of AF, less arterial hypertension, less vascular disease, less use of antiarrhythmics and consequently lower CHA2DS2-VASc and HAS-BLED Scores. There was no difference in arrhythmia-free survival between DOAC and VKA groups (DOAC: 86.6%, VKA: 76.7%, p = 0.286). ConclusionsDespite baseline characteristics favouring a better outcome of DOAC patients, arrhythmia-free survival was similar in both groups. Consequently, DOAC treatment did not have clinically relevant antiarrhythmic properties in these patients.

Presence of non-pulmonary vein foci in patients with atrial fibrillation undergoing standard ablation of pulmonary vein isolation: Clinical characteristics and long-term ablation outcome.

BackgroundThe clinical characteristics of atrial fibrillation (AF) resulting from non-pulmonary vein (PV) triggers remain unknown. This study aimed to evaluate the clinical characteristics of patients with AF caused by non-PV triggers, localization of non-PV foci, clinical differences, and clinical outcomes after catheter ablation in each AF focus.MethodsA total of 2967 patients who underwent initial catheter ablation for paroxysmal or persistent AF were examined. After PV isolation, all patients underwent high-dose isoproterenol infusion to assess the existence of non-PV foci.ResultsNon-PV foci were identified in 564 patients (19.2%). The localization of successfully ablated non-PV foci in 514 patients were the superior vena cava (SVC: 213 cases), interatrial septum (IAS: 125 cases), coronary sinus (CS: 98 cases), right atrium (RA: 125 cases), left atrium (LA: 114 cases), and unmappable (50 cases). Multivariate analysis revealed that female gender, low body mass index (BMI), non-paroxysmal AF (PAF), and sick sinus syndrome were independent and significant indicators of non-PV foci. In the multivariate analysis of each AF focus, female gender, low BMI, and non-PAF were significant predictors of IAS and CS foci, RA and IAS foci, and CS foci, respectively. In addition, dilatation of the LA was significantly associated with LA foci, whereas RA, LA, IAS, and CS foci were associated with AF recurrence.ConclusionThese findings could help to identify patients at a higher risk of AF caused by non-PV triggers and clarify the clinical difference according to the localization of non-PV foci.

Low-Voltage-Area Ablation in Paroxysmal Atrial Fibrillation: Extended Follow-Up Results of the Volcano Trial

Objectives: To compare long-term atrial fibrillation (AF)/atrial tachycardia (AT) recurrence rates and types of recurrent-atrial-tachyarrhythmia between treatment cohorts enrolled in the randomized controlled VOLCANO trial. Background: Although VOLCANO trial demonstrated comparable 1-year rhythm outcomes between patients with and without ablation targeting low-voltage areas (LVAs) in addition to pulmonary vein isolation among paroxysmal AF patients with LVAs, efficacy of LVA ablation on long-term outcomes are still unknown. Methods: Total of 402 paroxysmal AF patients were divided into 4 groups based on the results of voltage mapping: Group A, no LVA (n=336); group B, LVA ablation (n=30); group C, LVA presence without ablation (n=32); and group D, incomplete voltage map (n=4). Results: At 25 (23, 31) months after the initial ablation, AF/AT recurrence rates were 19% in group A, 57% in group B, 59% in group C, and 100% in group D. Recurrence rates were higher in patients with LVAs than those without (group A vs. B+C, p<0.0001), and were comparable between those with and without LVA ablation (group B vs. C, p=0.83). Among patients who underwent repeat ablation, ATs were more frequently observed in patients with LVAs (Group B+C, 50% vs. A, 14%, p<0.0001). In addition, LVA ablation increased the incidence of AT development (group B, 71% vs. C, 32%, p<0.0001), especially biatrial tachycardia (20% vs. 0%, p=0.01). Conclusion: Patients with LVAs demonstrated poor long-term rhythm outcomes irrespective of LVA ablation. ATs were frequently observed in patients with LVAs, and LVA ablation might exacerbate iatrogenic ATs. Clinical Trial Registration: UMIN-CTR, https://www.umin.ac.jp/ctr/, UMI23403

Ablation for paroxysmal atrial fibrillation\u2014real-life results from a middle-volume electrophysiology laboratory

IntroductionA significant improvement in safety and efficacy of ablation for paroxysmal atrial fibrillation (PAF) has been reported by experienced centers over recent years; however, data from real-life surveys and smaller electrophysiology (EP) laboratories have been less optimistic.AimTo asses efficacy of ablation for PAF in a middle-volume EP center over last years.MethodsRetrospective analysis of 1 year efficacy and safety of ablation for PAF in three cohorts of patients treated between 2011 and 2014 (period I), 2015–2017 (period II), and 2018–2019 (period III).ResultsOf 234 patients (mean age 57 ± 9 years, 165 males), 81 (35%) were treated in period I, 84 (36%) in period II, and 69 (29%) in period III. The overall efficacy of ablation during all analyzed periods was 67%. The overall efficacy of ablation increased over time—from 56% in period I to 68% in period II and 81% in period III. Significant improvement was achieved using radiofrequency ablation (RF) (53% in period I vs 82% in period III, and 55% in period II vs 82% in period III, p = 0.003 and 0.0012, respectively) whereas positive trend in the improvement of cryoballoon efficacy was NS. The rate of peri-procedural complications was 9% and it did not change significantly over time.ConclusionsThis real-life observational study from a medium volume EP center shows that progress in PAF ablation, especially RF, reported by highly-skilled centers, can be reproduced in real life by less experienced operators.

Visually Guided Laser Balloon Ablation for Paroxysmal Atrial Fibrillation

Visually Guided Laser Balloon Ablation for Paroxysmal Atrial Fibrillation

Long-Term Efficacy of Prophylactic Cavotricuspid Isthmus Ablation during Atrial Fibrillation Ablation in Patients Without Typical Atrial Flutter: a Prospective, Multicentre, Randomized Trial.

Background and ObjectivesCavotricuspid isthmus (CTI) block is easily achieved, and prophylactic ablation can be performed during atrial fibrillation (AF) ablation. However, the previous study was too small and short-term to clarify the efficacy of this block.MethodsPatients who underwent catheter ablation for paroxysmal AF were enrolled, and patients who had previous or induced atrial flutter (AFL) were excluded. We randomly assigned 366 patients to pulmonary vein isolation (PVI) only and prophylactic CTI ablation (PVI vs. PVI+CTI).ResultsThere was no significant difference in procedure time between the two groups because most CTI blocks were performed during the waiting time after the PVI (176.8±72.6 minutes in PVI vs. 174.2±76.5 minutes in PVI+CTI, p=0.75). All patients were followed up for at least 18 months, and the median follow-up was 3.4 years. The recurrence rate of AF or AFL was not different in the 2 groups (25.7% in PVI vs. 25.7% in PVI+CTI, p=0.92). The recurrence rate of any AFL was not significantly different in the 2 groups (3.3% in PVI vs. 1.6% in PVI+CTI, p=0.31). The recurrence rate of typical AFL also was not different (0.5% in PVI vs. 0.5% in PVI+CTI, p=0.99).ConclusionsIn this large and long-term follow-up study, prophylactic CTI ablation had no benefit in patients with paroxysmal AF without typical AFL.Trial RegistrationClinicalTrials.gov Identifier: NCT02031705

Atrial Fibrillation Ablation Using Vein of Marshall Ethanol Infusion.

Catheter ablation has become a cornerstone treatment for atrial fibrillation (AF). Pulmonary vein isolation is the accepted approach for paroxysmal AF ablation, but it is less effective for persistent AF. The vein of Marshall (VOM) is located in the epicardial left atrium and can be a source of AF triggers as well as a tract for autonomic nerves. It directly communicates with the underlying myocardium, including the left atrial ridge and the posterior mitral isthmus. This review discusses the latest evidence regarding the mechanisms, procedural aspects, and outcomes of VOM ethanol infusion when used as an adjunct to pulmonary vein isolation in patients with persistent AF.

Unique feature of novel activation mapping to identify the successful ablation site of atrial tachycardia

A 49-year-old man was referred to our hospital for catheter ablation of atrial tachycardia (AT; cycle length 360 ms). He previously underwent pulmonary vein isolation and cavotricuspid isthmus ablation for paroxysmal atrial fibrillation (AF). Conventional activation mapping with the high-density Rhythmia mapping system (Boston Scientific, Marlborough, MA) revealed the following features: (1) activation breaking out at the inferior wall below the left inferior pulmonary vein in a centrifugal pattern (Online Supplemental Figure 1) and (2) AF was observed inside the left pulmonary vein (LPV) (Figure 1A, a).

Dilated Accessory Hemiazygos Vein Mimicking Aortic Dissection in Setting of Absent Left Brachiocephalic Vein.

Although uncommon, aortic dissection can be rapidly fatal with a 20% out-of-hospital mortality which increases at a rate of 1 to 3% every hour [1]. An expeditious diagnosis of acute aortic dissection is therefore imperative. One of the most advantageous diagnostic modalities utilized in the setting of acute aortic dissection is a transesophageal echocardiogram (TEE). In an acute setting, TEE is preferred because of its ability to provide a timely and definitive diagnosis [2]. Despite its diagnostic convenience, clinicians must be aware that there are several entities that may mimic aortic dissection. One of these entities includes a dilated accessory hemiazygos vein. In this report, we present a case of a 66-year-old woman who was found to have a possible Stanford type B dissection in the descending thoracic aorta on a TEE exam in the context of work up prior to an elective electrophysiology study and ablation for paroxysmal atrial fibrillation. CT angiography, however, revealed a dilated accessory hemiazygos vein, a rare congenital vascular anomaly that could potentially mimic aortic dissection leading to misdiagnosis and potentially unnecessary interventions.

Impact of Left Atrial Bipolar Electrogram Voltage on First Pass Pulmonary Vein Isolation During Radiofrequency Catheter Ablation.

BackgroundFirst pass pulmonary vein isolation (PVI) is associated with durable isolation and reduced recurrence of atrial fibrillation (AF).ObjectiveWe sought to investigate the relationship between left atrial electrogram voltage using multielectrode fast automated mapping (ME-FAM) and first pass isolation with radiofrequency ablation.MethodsWe included consecutive patients (pts) undergoing first time ablation for paroxysmal AF (pAF), and compared the voltage characteristics between patients with and without first pass isolation. Left atrium (LA) adjacent to PVs was divided into 6 regions, and mean voltages obtained with ME-FAM (Pentaray, Biosense Webster) in each region and compared. LA electrograms with marked low voltage (<0.5 mV) were identified and the voltage characteristics at the site of difficult isolation was compared to the voltage in adjacent region.ResultsTwenty consecutive patients (10 with first pass and 10 without) with a mean age of 63.3 ± 6.2 years, 65% males, were studied. Difficult isolation occurred on the right PVs in eight pts and left PVs in three pts. The mean voltage in pts without first pass isolation was lower in all 6 regions; posterior wall (1.93 ± 1.46 versus 2.99 ± 2.19; p < 0.001), roof (1.83 ± 2.29 versus 2.47 ± 1.99; p < 0.001), LA-LPV posterior (1.85 ± 3.09 versus 2.99 ± 2.19, p < 0.001), LA-LPV ridge (1.42 ± 1.04 versus 1.91 ± 1.61; p < 0.001), LA-RPV posterior (1.51 ± 1.11 versus 2.30 ± 1.77, p < 0.001) and LA-RPV septum (1.55 ± 1.23 versus 2.31 ± 1.40, p < 0.001). Patients without first pass isolation also had a larger percentage of signal with an amplitude of <0.5 mV for each of the six regions (12.8% versus 7.5%). In addition, the mean voltage at the site of difficult isolation was lower at 8 out of 11 sites compared to mean voltage for remaining electrograms in that region.ConclusionIn patients undergoing PVI for paroxysmal AF, failure in first pass isolation was associated with lower global LA voltage, more marked low amplitude signal (<0.5 mV) and lower local signal voltage at the site with difficult isolation. The results suggest that a greater degree of global and segmental fibrosis may play a role in ease of PV isolation with radiofrequency energy.

Clinical outcomes of ablation versus non-ablation therapy for atrial fibrillation in Japan: analysis of pooled data from the AF Frontier Ablation Registry and SAKURA AF Registry.

Whether ablation for atrial fibrillation (AF) is, in terms of clinical outcomes, beneficial for Japanese patients has not been clarified. Drawing data from 2 Japanese AF registries (AF Frontier Ablation Registry and SAKURA AF Registry), we compared the incidence of clinically relevant events (CREs), including stroke/transient ischemic attack (TIA), major bleeding, cardiovascular events, and death, between patients who underwent ablation (n = 3451) and those who did not (n = 2930). We also compared propensity-score matched patients (n = 1414 in each group). In propensity-scored patients who underwent ablation and those who did not, mean follow-up times were 27.2 and 35.8months, respectively. Annualized rates for stroke/TIA (1.04 vs. 1.06%), major bleeding (1.44 vs. 1.20%), cardiovascular events (2.15 vs. 2.49%) were similar (P = 0.96, 0.39, and 0.35, respectively), but annualized death rates were lower in the ablation group than in the non-ablation group (0.75 vs.1.28%, P = 0.028). After multivariate adjustment, the risk of CREs was statistically equivalent between the ablation and non-ablation groups (hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.71-1.11), but it was significantly low among patients who underwent ablation for paroxysmal AF (HR 0.68 [vs. persistent AF], 95% CI 0.49-0.94) and had a CHA2DS2-VASc score < 3 (HR 0.66 [vs. CHA2DS2-VASc score ≥ 3], 95% CI 0.43-0.98]). The 2-year risk reduction achieved by ablation may be small among Japanese patients, but AF ablation may benefit those with paroxysmal AF and a CHA2DS2-VASc score < 3.

Prospective implementation of a same-day discharge protocol for catheter ablation of paroxysmal atrial fibrillation.

PurposeOvernight stays associated with catheter ablation (CA) for paroxysmal atrial fibrillation (PAF) account for a significant proportion of treatment cost. Same-day discharge (SDD) after CA may be attractive to both patients and hospitals, especially in light of current restrictions on overnight stays due to COVID-19. This study reports on the selection criteria, protocol, and safety of SDD after CA of PAF.MethodsPatients undergoing CA for PAF were evaluated to assess the risk of groin, respiratory, cardiac, or bleeding complications. SDD eligibility criteria were stable anticoagulation with no bleeding history, systolic heart failure, respiratory conditions, or interventional procedures within 60 days, and recommended BMI < 35. Patient proximity to the hospital was also considered. Anesthesia with propofol was used, and ablations were performed with a contact force catheter. Patients rested for 6 h post-procedure and then ambulated over 1–2 h. Discharge followed if they were stable without evidence of complications. A nurse called all patients the following morning to elicit evidence of complications.ResultsOf 44 planned SDD procedures between April 2017 and June 2018, 41 resulted in SDD after 7.2 ± 1.0 h, 2 patients stayed overnight for observation, and one by choice. Average age was 59 ± 10 years with CHA2DS2-VASc of 1.6 ± 1.1. No SDD-related complications occurred, and no return visits resulted from the follow-up calls.ConclusionAppropriate low-risk patients identified by well-defined clinical criteria can be safely discharged the same day after CA for PAF. Evaluation in a larger population across different centers is required for generalizability of this SDD protocol.

Presence of a left common pulmonary vein and pulmonary vein anatomical characteristics as predictors of outcome following cryoballoon ablation for paroxysmal atrial fibrillation.

Pulmonary vein (PV) isolation using cryoballoon ablation (CBA) is a common therapy for patients with drug-refractory paroxysmal atrial fibrillation (PAF). However, initial CBA is successful in only 70-80% of patients. The role of an atypical left common PV (LCPV) and PV anatomical indices on CBA outcomes remains unclear. We followed 80 patients (age 60.7 ± 9.7, 31 % women) with PAF undergoing CBA for 1-year post-procedure for the development of recurrent atrial arrhythmias (AA). Recurrence was assessed by documented AA on EKG or any form of long-term cardiac rhythm monitoring. The presence of an LCPV and individual PV diameters were evaluated using cardiac CT. Based on the maximum and minimum PV ostial diameters, the eccentricity index (EI), ovality index (OI), and PV ostial area (PVA) were calculated for all the veins. A multivariable Cox-proportional hazard model assessed whether the presence of an LCPV or PV anatomic indices (EI, OI, and PVA) predicted recurrence of AA following CBA. After 1-year follow-up, 19 (23.7%) participants developed recurrence of AA. On multivariable regression, the presence of an LCPV did not predict the recurrence of AA (p = 0.38). Among the PV anatomical indices, on univariate analysis, only the area of the left inferior PV showed a trend towards predicting recurrence, though this result was not significant on multivariate analysis (p = 0.09). In patients with PAF, neither the presence of an LCPV nor individual PV anatomical indices predicted recurrence of AA following CBA.

The effect of left atrial remodeling after cryoballoon ablation and radiofrequency ablation for paroxysmal atrial fibrillation.

BackgroundCryoballoon ablation (CBA) and radiofrequency ablation (RFA) are the most common procedures used to treat refractory atrial fibrillation (AF) and are performed through pulmonary vein isolation (PVI). Studies have shown that CBA can approximately match the therapeutic effects of RFA against AF. However, few studies have investigated the difference between CBA and RFA of the effects on left atrial remodeling for paroxysmal AF.ObjectiveAtrial remodeling is considered pivotal to the occurrence and development of AF, therefore we sought to assess the influence of atrial remodeling in patients with paroxysmal AF after CBA and RFA in this study.MethodsIn this nonrandomized retrospective observational study, we enrolled 328 consecutive patients who underwent CBA or RFA for refractory paroxysmal AF in May 2014 to May 2017 in our hospital. After propensity score matching, 96 patients were included in the CBA group, and 96 were included in the RFA group. Patients were asked to undergo a 12‐lead electrocardiogram, a 24‐h Holter monitor, and an echocardiogram and to provide their clinical history and symptoms at 6 months and 1, 2, and 3 years postprocedurally. Electrical remodeling of the left atrium was assessed by P wave dispersion (Pdis); structural remodeling was assessed by the left atrium diameter (LAD) and left atrial volume index (LAVI) during scheduled visits.ResultsAs of January 2020, compared with baseline, at 1 year, 2 years, and 3 years after ablation, the average changes in Pdis (∆Pdis), LAD (∆LAD), and LAVI (∆LAVI) were significant in both the CBA and RFA groups. Six months after ablation, ∆Pdis, ∆LAD, and ∆LAVI were greater in the CBA group than in the RFA group. There was no significant difference between the two groups in AF/flutter recurrence, but the AF/flutter‐free survival time of CBA group may be longer than RFA group after 2 years after ablation. A higher ∆Pdis, ∆LAD, or ∆LAVI at 1 year after ablation may increase AF/flutter‐free survival.ConclusionsAlthough CBA and RFA are both effective in left atrial electrical and structural reverse‐remodeling in paroxysmal AF, CBA may outperform RFA for both purposes 6 months after ablation. However, during long‐term follow‐up, there was no significant intergroup difference.

Abstract 16277: Evaluation of Left Peri Atrial Cardiac Sympathetic Activity Using Mibg Scintigraphy Before and After Cryoballoon Ablation of Paroxysmal Atrial Fibrillation

Introduction: Accelerated cardiac sympathetic activity has been implicated in the development of atrial fibrillation. Ablation or excision of atrial epicardial ganglia for the treatment of atrial fibrillation has been reported. However, visualization of the atrial neural network is considered difficult. We attempted to image the sympathetic innervation with 123 I-metaiodobenzylguanidine (MIBG) using a novel solid-state whole-body scanner (VERITON). Methods: We performed pulmonary vein isolation using a cryoballoon in 10 patients with paroxysmal atrial fibrillation. MIBG images using specific processing were evaluated before and 3 months after ablation to evaluate the neural network of the left peri-atrial cardiac sympathetic activity and its response to ablation. Discrete epicardial accumulation of MIBG was identified using MIBG images fused with atrial computed tomography images. We quantitatively calculated the discrete MIBG accumulation in each pulmonary vein within 2 cm from its ostium, which may have been modified by balloon ablation. Results: Discrete MIBG accumulation was generally reproducible in the pre- and postoperative evaluations. The discrete MIBG accumulation value was 2.8 per case, with an average count of 4.15х10 5 PROPCNTS. Of the overall 28 accumulations, 15 had disappeared and three had changed in accumulation level and location after ablation. There was no specific pattern of sympathetic image modification. However, the group in which accumulation disappeared had a significantly smaller cross-sectional area of the pulmonary vein than the group in which it did not (17.2±3.4 mm vs 19.7±1.7 mm, p=0.0056). For reference, the average cryoballoon size was 28 mm. Conclusions: The sympathetic innervation of the left atrium was visualized using MIBG imaging, and the image was modified by cryoballoon ablation. The ability to image sympathetic nerve modification by catheter ablation will be clinically useful.

Case report: Managing profound circulatory collapse post-atrial fibrillation ablation: a methodical approach.

BackgroundCirculatory collapse during/post-pulmonary vein (PV) isolation by cryo-balloon ablation is a Cardiology emergency that has multiple potential causes and requires a methodical investigative approach. Some of the complications that can arise include cardiac tamponade, bleeding/vascular injury, anaphylaxis, Addisonian crisis, acute pulmonary embolism, acute PV stenosis, oesophageal injury, and vagal reaction.Case summaryHere, we present a case of a 76-year-old lady who developed profound circulatory collapse during an elective pulmonary vein isolation by cryo-balloon ablation for symptomatic paroxysmal atrial fibrillation (AF). Cardiac tamponade, bleeding/vascular injury, and other less common causes were excluded. She only responded transiently to fluid resuscitation and developed intermittent bradyarrhythmias and hypotension which responded to isoprenaline. She was discharged home at Day 3 post-AF ablation after remaining well and continued to do so at follow-up.DiscussionCirculatory collapse during/post-PV cryo-balloon ablation is a Cardiology emergency that has multiple potential causes. The ganglionate plexi form part of the cardiac intrinsic autonomic nervous system (ANS) and are located close to the left atrial–PV junctions. The presence of vagal response has been observed to be a marker of ANS modulation although its significance on the long-term outcome post-ablation has yet to be elucidated. The true cause of our patient’s profound circulatory collapse is uncertain but a vital learning point in this case is the systematic exclusion of common and potentially life-threatening complications following AF ablation. A persistent vagal reaction secondary to PV cryo-balloon ablation can usually be managed with supportive medical therapy as demonstrated in our case.

Association between the locations of non-pulmonary vein triggers and ablation outcomes in repeat procedures after cryoballoon ablation of paroxysmal atrial fibrillation.

We examined the characteristics of non-pulmonary vein (PV) triggers in repeat ablation after cryoballoon ablation for paroxysmal atrial fibrillation (PAF). This study evaluated 119 patients undergoing a second ablation procedure for recurrent atrial tachyarrhythmia (ATA) after cryoballoon PV isolation (CB-PVI) for PAF. Fifty-three of 119 (45%) patients had PV reconnection. All reconnected PVs were isolated. No non-PV triggers were elicited in 42/119 (35%) patients (NNPV group). In 77/119 (65%) patients, 139 isoproterenol-induced non-PV triggers, including 45 triggers that initiated AF, were identified. Non-PV triggers initiating AF were observed at the superior vena cava (SVC), left atrial posterior wall (LAPW) including the PV antra, interatrial septum, right atrium, left atrial appendage/mitral anulus, and coronary sinus in 14 (12%), 10 (8%), 8 (7%), 7 (6%), 4 (3%), and 2 (2%) patients, respectively. Non-PV triggers originated from only the SVC and/or LAPW including the PV antra, and the SVC and/or LAPW was isolated in 18/119 (15%) patients (SVC/LAPW group). Non-PV triggers originating from other sites were focally ablated in 59/119 (50%) patients (OS group). During a median 461days of follow-up, 39/42 (93%), 17/18 (94%), and 38/59 (64%) patients in the NNPV, SVC/LAPW, and OS groups, respectively, remained ATA recurrence-free. The recurrence rate was higher in the OS group than in the NNPV (P = 0.005) or SVC/LAPW groups (P = 0.042). Over half of patients had non-PV triggers at subsequent ablation after CB-PVI. Non-PV triggers from the SVC/LAPW can be eliminated more successfully than triggers from other sites.