Complication Of Pulmonary Vein Isolation Research Articles

Pulsed-field ablation does not induce esophageal and periesophageal injury-A new esophageal safety paradigm in catheter ablation of atrial fibrillation.

Esophageal injury is one of the most serious complications of pulmonary vein isolation (PVI) with thermic energy sources. Better tissue selectivity of primarily non-thermic pulsed field ablation (PFA) may eliminate collateral injury, particularly the risk of atrio-esophageal fistula (AEF). To compare the incidence of any (peri)-esophageal injury following PVI using PFA to thermic energy sources. Using endoscopy, endoscopic ultrasound, and electrogastrography before and after PVI, esophageal and periesophageal injury (mucosal lesions, food retention, periesophageal edema, or vagal nerve injury) were assessed following PFA and radiofrequency (RF)- or cryoballoon (CB)-PVI. Between December 2022 and February 2023, 20 patients (67 ± 10 years, 53% male) undergoing PFA (Farapulse, Boston Scientific) for atrial fibrillation (AF) were studied and compared with a previous cohort of 57 patients who underwent thermic PVI (CB: n = 33; RF: n = 24). Following PFA-PVI, none of the patients had mucosal lesions, food retention, or ablation-induced vagal nerve injury; fourpatients showed periesophageal edema. Following thermic ablation, 33/57 patients (58%) showed esophageal and/or periesophageal injury (CB: 21/33 [64%], RF: 12/24 [50%]), in detail 4/57 mucosal lesions, 18/57 food retention, 17/57 vagal nerve injury, and 20/52 edema. Midterm success rates were similar for all energy sources. In contrast to thermic ablation tools, PFA is not associated with relevant esophageal and periesophageal injury, and might, therefore, reduce or eliminate the risk of potentially lethal AEF in interventional treatment of AF. The etiology of ablation-induced periesophageal edema is unknown but has not been shown to be related to lesion progression.

Incidence and predictors of stroke and silent cerebral embolism following very high-power short-duration atrial fibrillation ablation.

Cerebral thrombo-embolism is a dreaded complication of pulmonary vein isolation (PVI) for atrial fibrillation; its surrogate, silent cerebral embolism (SCE) can be detected by diffusion-weighted brain magnetic resonance imaging (bMRI). Initial investigations have raised a concern that very high-power, short-duration (vHPSD; 90 W/4 s) temperature-controlled PVI with the QDOT Micro catheter may be associated with a higher incidence of SCE compared with low-power long-duration ablation. We aimed to assess the incidence of procedural complications of vHPSD PVI with an emphasis on cerebral safety. We enrolled 328 consecutive patients undergoing their PVI procedure using vHPSD. A subgroup of 61 consecutive patients underwent diffusion-weighted bMRI within 24 h of the procedure, and incidence and predictors of SCE were studied. The mean procedure time and left atrial dwell time for the overall cohort were 69.6 ± 24.1 and 46.5 ± 21.5 min, respectively. First-pass isolation was achieved in 82%. No stroke or transient ischaemic attack occurred. Silent cerebral embolism was identified in 5 of 61 patients (8.2%). Silent cerebral embolism following procedures was significantly associated with lower baseline generator impedance (105.8 vs. 112.6 Ω, P < 0.0001) and with intermittent loss of catheter-tissue contact during ablation (14.1% vs. 6.1%, P < 0.0001). Very high-power, short-duration PVI is a safe technique with an excellent acute success rate. Silent cerebral embolism incidence in our cohort was below the previously reported range, with no clinically overt cerebral complications. Lower baseline generator impedance and loss of contact during ablation may contribute to a higher risk of SCEs.

Differences in acute outcomes and complications of pulmonary vein isolation using pulsed field ablation with or without 3D mapping system for paroxysmal atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulsed field ablation (PFA) has recently been introduced as a novel routine ablation technology for paroxysmal atrial fibrillation (PAF). It is also used as off-label therapy for persistent AF. PFA can be performed "cryo-style" using fluoroscopy only, or additional pre- and post-ablation high-density 3D bipolar voltage maps can be performed to assess lesion formation and acute pulmonary vein isolation. We compared acute outcome after PFA using fluoroscopy only (X-ray) vs. PFA guided by 3D mapping (3D). Methods In patients with AF, PVI in conscious sedation using a steerable sheath and a pentaspline over-the-wire basket and flower PFA catheter was performed. In a subset of patients, pre- and post-ablation high-density bipolar voltage 3D maps (Carto 3D) were performed. Procedural parameters, acute success and in-hospital safety were assessed. Results A total of 4 operators treated 218 patients (mean age 66 years (range 35–86), female 43%, mean BMI 28 kg/m2 (range 20-42), mean CHA2DS2-VaSc score of 2,5 (range 0-7), first-time ablation 93%, paroxysmal AF/persistent AF/re-do 72/21/7%). Mean duration since first AF diagnosis was 42 months (range 1-336). Most procedures were performed under deep conscious sedation without intubation (99%). There were no selection criteria for the use of 3D mapping. Pre- and post-ablation high-density maps were performed in 28% of cases. Skin-to skin procedure time was 54±22 in the X-ray group vs. 123±35 min in the 3D group, respectively (p&amp;lt;0,0001). Fluoroscopy time was 17±7 in the X-ray group vs. 20±6 in the 3D group, respectively (p&amp;lt;0,01). Acute pulmonary vein isolation rate was 100% in both groups. There were no phrenic nerve palsies or esophageal complications. Major complications (3,7%) were pericardial tamponade (2,8%) and stroke (0,9%); one stroke resulted in death (0,5%). They occurred in 3,2% of patients in the X-ray group (3 pericardial tamponades, 2 strokes) vs. 4,8% in the 3D group (3 pericardial tamponades), respectively (p=ns). Minor complications (1,4%) were vascular (0,5%) and transient ischemic attack (TIA) (0,9%). Conclusions In a large, single center cohort of unselected patients, PVI using PFA with or without 3D mapping system resulted in a similar acute outcome and safety profile. Procedure and fluoroscopy times were significantly shorter in the fluoroscopy only group. There were no PFA-specific complications, but the frequency of catheter complications in this relatively old patient population demonstrates that there is still room for improvement.

Ultra-microhistological study of nonthermal irreversible electroporation on the esophagus

Esophageal ulceration and even fistula are severe complications of pulmonary vein isolation using traditional thermal ablation. Nonthermal irreversible electroporation (NTIRE) is a new technique for pulmonary vein isolation in patients with atrial fibrillation. NTIRE has been shown to be a safe method for pulsed electroporation near the esophagus. NTIRE preserves the structural framework of the esophagus and allows for rapid recovery of the whole layers of the esophagus. The purpose of this study was to elucidate the ultrastructural changes and cytological mechanisms of cell regeneration and tissue repair after esophageal electroporation. The parameter combination of 2000 V/cm multiplied by 90-pulse output was directly applied to the esophagus in 60 New Zealand rabbits, and ultrastructure analysis of the esophagus was implemented subsequently. NTIRE predominantly triggered apoptosis of esophageal cells shortly after electroporation. Since the tissue structural framework was preserved, esophageal cells could regenerate through self-replication within 4 weeks. Complete anatomical repair can eventually be achieved through structural remodeling, and no lumen stenosis, ulcer, or fistula was observed in the ablated segment. Monophasic, bipolar NTIRE pulses delivered using plate electrodes in an esophageal model demonstrates no irreversible ultra-micropathological changes to the esophagus after 4 weeks.

Nonthermal Irreversible Electroporation to the Esophagus: Evaluation of Acute and Long-Term Pathological Effects in a Rabbit Model.

BackgroundEsophageal ulceration and fistula are severe complications of pulmonary vein isolation using thermal ablation. Nonthermal irreversible electroporation (NTIRE) is a promising new technology for pulmonary vein isolation in patients with atrial fibrillation. NTIRE ablation technology has been used to treat atrial fibrillation; however, the effects of NTIRE on esophageal tissue have not been clearly described.Methods and ResultsA typical NTIRE electrical protocol was directly applied to esophagi in 84 New Zealand rabbits. Finite element modeling and histological analysis with 120 slices were used to analyze electric field intensity distribution and subsequent tissue changes. A parameter combination of 2000 V/cm multiplied by 90 pulses output is determined to be an effective ablation parameters combination. Within 16 weeks after ablation, no obvious lumen stenosis, epithelial erythema, erosion, ulcer, or fistula was observed in the esophageal tissue. NTIRE effectively results in esophageal cell ablation to death, and subsequently, signs of recovery gradually appear: creeping replacement and regeneration of epithelial basal cells, repair and regeneration of muscle cells, structural remodeling of the muscle layer, and finally the restoration of clear anatomical structures in all layers.ConclusionsMonophasic, bipolar NTIRE delivered using plate electrodes in a novel esophageal injury model demonstrates no histopathologic changes to the esophagus at 16 weeks. Data of this study suggest that electroporation ablation is a safe modality for pulsed electroporation ablation near the esophagus.

P472Cerebral thromboembolic risk in atrial fibrillation ablation: a direct comparison of vitamin K antagonists versus non-vitamin K-dependent oral anticoagulants

Abstract Aims Cerebral thromboembolic events are well-known complications of pulmonary vein isolation (PVI) and can manifest as stroke or silent cerebral embolic lesions. Over the last years, the preferred oral anticoagulation in atrial fibrillation (AF) shifted from vitamin K antagonists (VKA) to non-vitamin K-dependent oral anticoagulants (NOAC). The aim of this study was to compare the incidence of cerebral embolic lesions after AF ablation in patients on VKA versus patients on NOAC, and to identify corresponding clinical and procedural risk factors. Methods A total of 421 patients undergoing PVI (by radiofrequency catheter or cryoballoon) were prospectively included into the study. Of these, 43.7% were on VKA and 56.3% on NOAC treatment. In the NOAC group 38% of patients had an interruption of anticoagulation for 24-36 hours. All patients underwent pre- and postprocedural cerebral magnetic resonance imaging. Results Periprocedural cerebral lesions occurred in 13.1% overall. Of these, three (0.7%) resulted in symptomatic cerebrovascular accidents. Incidence of cerebral lesions was significantly higher in patients on NOAC compared to VKA (16% vs. 9.2% respectively, p = 0.04), as well as in patients that had intraprocedural cardioversions compared to no cardivoersions (19.5% vs. 10.4% respectively, p = 0.03). In multivariate analysis both parameters were found to be independent risk factors for cerebral embolism. No significant difference between interrupted and uninterrupted NOAC administration could be detected. Conclusions In patients undergoing AF ablation, we identified the use of NOAC and intraprocedural cardioversion as independent risk factors for the occurrence of periprocedural cerebral embolic lesions. Abstract Figure. Incidence of cerebral embolic lesions

Cerebral thromboembolic risk in atrial fibrillation ablation: a direct comparison of vitamin K antagonists versus non-vitamin K-dependent oral anticoagulants.

Cerebral thromboembolic events are well-known complications of pulmonary vein isolation (PVI) and can manifest as stroke or silent cerebral embolic lesions. The aim of this study was to compare the incidence of cerebral embolic lesions (including silent cerebral embolism and stroke) after AF ablation in patients on vitamin K antagonists versus patients on non-vitamin K-dependent oral anticoagulants, and to identify corresponding clinical and procedural risk factors. A total of 421 patients undergoing PVI were prospectively included into the study. Of these, 43.7% were on VKA and 56.3% on NOAC treatment (dabigatran, rivaroxaban, apixaban, and edoxaban). In the NOAC group, 38% of patients had an interruption of anticoagulation for 24-36h. All patients underwent pre- and postprocedural cerebral magnetic resonance imaging. Periprocedural cerebral lesions occurred in 13.1% overall. Of these, three (0.7%) resulted in symptomatic cerebrovascular accidents and 52 (12.4%) in silent cerebral embolic lesions. Incidence of cerebral lesions was significantly higher in patients on NOAC compared with VKA (16% vs. 9.2%, respectively, p = 0.04), and in patients who had intraprocedural cardioversions compared with no cardivoersions (19.5% vs. 10.4%, respectively, p = 0.03). In multivariate analysis, both parameters were found to be independent risk factors for cerebral embolism. No significant difference between interrupted and uninterrupted NOAC administration could be detected. In patients undergoing AF ablation, we identified the use of NOAC and intraprocedural cardioversion as independent risk factors for the occurrence of periprocedural cerebral embolic lesions.

Acute and Long-Term Effects of Full-Power Electroporation Ablation Directly on the Porcine Esophagus.

Esophageal ulceration and fistula are complications of pulmonary vein isolation using thermal energy sources. Irreversible electroporation is a novel, nonthermal ablation modality for pulmonary vein isolation. A single 200 J application can create deep myocardial lesions. Acute and chronic effects of this new energy source on the esophagus are unknown. In 8 pigs (±70 kg), the suprasternal esophagus was surgically exposed. A linear suction device with a single 35-mm long and 6-mm wide protruding linear electrode inside a plastic suction cup was used for ablation. Single, nonarcing, nonbarotraumatic, cathodal 100 and 200 J applications were delivered at 2 different sites on the anterior esophageal adventitia. No proton-pump inhibitors were administered during follow-up. Esophagoscopy was performed at days 2 and 7. After euthanasia at day 60, the esophagus was evaluated visually and histologically. All ablations were uneventful. Esophagoscopy at day 2 showed small white densities in the ablated areas, which appeared to be small intraepithelial vesicles. No epithelial erythema, erosions, or ulcerations were seen. At day 7, all densities had disappeared, and all esophaguses appeared completely normalized. After euthanasia, there were no macroscopically visible lesions on the adventitia or epithelium. Histologically, a small scar was observed at the outer part of the muscular layer, whereas the mucosa and submucosa were normal. Esophageal architecture remains unaffected 2 months after irreversible electroporation, purposely targeting the adventitia. Irreversible electroporation seems to be a safe modality for catheter ablation near the esophagus.

Data on procedural handling and complications of pulmonary vein isolation using the pulmonary vein ablation catheter GOLD®.

The second-generation multi-electrode-phased radiofrequency pulmonary vein ablation catheter (PVAC GOLD(®)) was redesigned with the intent to improve its safety and efficacy. Using a prospectively designed single-centre database, we retrospectively analysed 128 consecutive patients (102 paroxysmal and 43 female) who underwent their first pulmonary vein isolation with the PVAC GOLD(®). The analysis focused on procedural data as well as in-hospital complications. Baseline characteristics of the patient collective were as follows: mean age 57.9 years, mean CHA2DS2-VASC was 1.73 ± 1.30; structural heart disease was present in seven patients. The PVAC GOLD(®) exhibited procedure durations of 123.1 min ± 27.9, duration of energy delivery was 18.3 min ± 11.4, and fluoroscopy duration was 16.0 min ± 7.7. The redesigned catheter shows major complication [major bleeding, transitory ischaemic attack (TIA), and pericardial tamponade] rates of 2.3% (n = 3). The overall rate of adverse events was 5.4% (n = 7). Bleeding complications were observed in three patients (2.3%), in particular there were two cases (1.6%) of minor bleeding and one case (0.8%) of major bleeding. Two patients suffered pericardial effusion, but there was no need for pericardiocentesis. Besides one TIA, there was no other thrombo-embolic event. Furthermore, one case of post-procedural fever was observed. No deaths, stroke, or haemorrhagic shock occurred. Of the 510 pulmonary veins, 508 could be reached with the PVAC GOLD(®) device using a non-steerable long sheath. The PVAC GOLD(®) seems to have an acceptable safety profile. The handling is comparable with the previous generation PVAC(®).

The incidence, diagnosis, and management of pulmonary vein stenosis as a complication of atrial fibrillation ablation

Pulmonary vein isolation (PVI) during ablation of atrial fibrillation (AF) is associated with pulmonary vein stenosis (PVS). Although the reported incidence of PVS has fallen in recent years, the precise rate of PVS is unknown. Coherent guidelines for screening and treatment of PVS are not established. We reviewed literature to investigate the incidence, diagnosis, and management of PVS as a complication of PVI. We reviewed 41 manuscripts that described a total of 4,615 subjects (median, 84 subjects/study). The incidence of PVS after PVI reported in literature from 1999 to 2004 ranges from 0 to 44% (mean, 6.3%; median, 5.4%), whereas studies after 2004 report an incidence of 0-19% (mean, 2%; median, 3.1%; p < 0.001). PVS symptoms typically occur with reduction of lung perfusion by 20-25%. Variable criteria exist for diagnosis of PVS by magnetic resonance imaging, computed tomography, and perfusion imaging. The restenosis rate for treatment with balloon angioplasty ranges from 30 to 87% (mean, 60%; median, 47%), compared with immediate stenting that ranges from 14 to 57% (mean, 34%; median, 33%). Recent peer-reviewed articles suggest that PVI carries a 3-8% risk of developing PVS, but they likely underestimate the incidence of PVS, as specific screening and diagnostic guidelines are not established. Imaging modalities should be used to screen patients after ablation of AF since early recognition of PVS improves treatment outcomes. Treatment with angioplasty and stent placement can improve symptoms and lung perfusion but the benefit of treatment with immediate stent placement remains controversial. It is critical to maintain a high clinical index of suspicion for PVS in at-risk individuals to ensure timely detection and treatment.

Does PV isolation with a multipolar ablation catheter influence the incidence of PV stenosis in patients with paroxysmal or persistent AF?

Introduction: During last years, PVI has developed as a cornerstone therapy for ablation in patients with paroxysmal/persistant AF. With a circular ablation catheter, all pulmonary veins can be isolated with few RF energy applications and without the use of additional mapping systems. The novel technology allowes circular lesions about all 10 electrodes under energy oscillation. Pulmonary vein stenosis (PVST) is an unrequested complication of pulmonary vein isolation (PVI), therefore we reviewed the incidence of PVST after PVI with the PVAC®. Patients and results: 589 patients with paroxysmal or persistent/permanent atrial fibrillation underwent pulmonary vein isolation by using the PVAC®. We isolated a total of 2242 pulmonary veins, in detail 478 left superior PVs, 478 left inferior PVs, 111 left common PVs, 586 right superior PVs, 586 right inferior PVs, and 3 right common PVs. In a subgroup of consecutive 228 patients had CT-scans after 6 months (64-MSCT, slice thickness 0,6 mm, 40 ml saline and 80 ml contrast agent i.v.). As a result we found 1 mild (-50%) pulmonary vein stenosis (see table 1). PV-stenosis after PVAC Summary and conclusion: PVI by using the PVAC®-catheter not only gives equivalent results, but additionally seems to benefit prevention of pulmonary vein stenosis.

Phrenic Nerve Injury: An Underrecognized and Potentially Preventable Complication of Pulmonary Vein Isolation Using a Wide‐Area Circumferential Ablation Approach

Phrenic nerve injury (PNI) is a well-known, although uncommon, complication of pulmonary vein isolation (PVI) using radiofrequency energy. Currently, there is no consensus about how to avoid or minimize this injury. The purpose of this study was to determine how often the phrenic nerve, as identified using a high-output pacing, lies along the ablation trajectory of a wide-area circumferential lesion set. We also sought to determine if PVI can be achieved without phrenic nerve injury by modifying the ablation lesion set so as to avoid those areas where phrenic nerve capture (PNC) is observed. We prospectively enrolled 100 consecutive patients (age 61.7 ± 9.2 years old, 75 men) who underwent RF PVI using a wide-area circumferential ablation approach. A high-output (20 mA at 2 milliseconds) endocardial pacing protocol was performed around the right pulmonary veins and the carina where a usual ablation lesion set would be made. A total of 30% of patients had PNC and required modification of ablation lines. In the group of patients with PNC, the carina was the most common site of capture (85%) followed by anterior right superior pulmonary vein (RSPV) (70%) and anterior right inferior pulmonary vein (RIPV) (30%). A total of 25% of PNC group had capture in all 3 (RSPV, RIPV, and carina) regions. There was no difference in the clinical characteristics between the groups with and without PNC. RF PVI caused no PNI in either group. High output pacing around the right pulmonary veins and the carina reveals that the phrenic nerve lies along a wide-area circumferential ablation trajectory in 30% of patients. Modification of ablation lines to avoid these sites may prevent phrenic nerve injury during RF PVI.

Abstract 17260: Percutaneous Recanalization of Totally Occluded Pulmonary Veins After Pulmonary Vein Isolation

Background: Pulmonary vein total occlusion (PVO) is an uncommon complication of pulmonary vein isolation (PVI). We have previously published our early experience with diagnosis and treatment of PVO, and now describe mid-term follow-up of attempted recanalization. Methods: Patients with angiographic PVO were identified from our catheterization database. Medical records and catheterization reports were reviewed for: symptoms, flow to affected lung quadrant, time from PVI to diagnosis of PVO, anatomic characteristics of occluded veins, and procedural details. Patients with severely hypoplastic veins had staged intervention with initial balloon angioplasty followed by stenting 2-4 months later to allow for vessel growth. Symptoms, quadrant flow, and status of the vein at last follow-up were ascertained. Results: Between 6/2005 and 6/2011, 14 patients with PVO underwent attempted recanalization. Median age was 56.9 (0.2-67.3) years, weight 88 (5.0-111.4) kg. Symptoms included dyspnea in 11, cough in 4, hemoptysis in 5 with a mean NYHA class of 2.1 ± 0.8. Flow to affected lung quadrant was severely diminished at 5.9 ± 3.7%. Median time from PVI to recanalization attempt was 16.5 (2.0-62.7) months. Reference vessel diameter was 5.3 ± 2.0 mm and length of occluded segment 8.3 ± 6.0 mm. Recanalization results are summarized in Table 1. At median follow-up of 13.3 (0-41.3) months, 10 veins remain patent with minimal diameter of 6.1 ± 2.7 mm, reference diameter of 7.8 ± 3.1 mm, and flow to affected lung quadrant 12.3 ± 7.2%, all significantly greater than pre-intervention (p&lt;0.03). Of 10 patients completing staged intervention, 5 have no symptoms and mean NYHA class decreased to 1.5 ± 0.7. Conclusions: PVO recanalization can be accomplished with reasonable acute and mid-term vessel patency and significant improvement in symptoms and flow to affected lung quadrant. However, recurrent stenosis is common and repeated interventions are often necessary to maintain vessel patency.

Evaluation of Pulmonary Vein Stenosis After Pulmonary Vein Isolation Using a Novel Circular Mapping and Ablation Catheter (PVAC)

Pulmonary vein stenosis (PVST) is a well-known complication of pulmonary vein isolation (PVI). Specific anatomically designed ablation catheters for antral PVI have not been evaluated with regard to the incidence of PVST. We investigated the incidence, severity, and characteristics of PVST after PVI with the Pulmonary Vein Ablation Catheter (PVAC) and phased radiofrequency technology. A total of 100 patients (55 men) underwent PVI for atrial fibrillation using the PVAC. PVI was guided by selective angiography of each pulmonary vein (PV) in 70 (70%) patients and by reconstructed 3D atriography (ATG) in 30 (30%) patients. Gadolinium-enhanced MRI or multidetector CT was performed in all patients before treatment and 93±78 days after PVI. PVST was classified as follows: insignificant (<25%), mild (25%-50%), moderate (50%-75%), or severe (>75%). A total of 410 PVs were analyzed. Cardiac imaging demonstrated a detectable narrowing of the PV diameter in 23 (23%) patients and in 28 (7%) PVs. In detail, insignificant PVST was observed in 12 (2.9%) PVs, mild PVST in 15 (3.7%), and moderate PVST in 1 (0.2%). No instances of severe PVST were observed. The use of 3D-ATG was associated with a lower incidence of PVST (0.8% [95% CI, 0.0%-2.2%] versus 5.4% [95% CI, 2.7%-8.1%], P=0.027). To our knowledge, this study is the first to report the incidence of PVST using the PVAC. In this regard, the PVAC seems to be safe if used in an experienced center. In addition, the use of 3D-ATG may decrease the risk of PVST.

Catheter Entrapment in a Pulmonary Vein: A Unique Complication of Pulmonary Vein Isolation

Ablation strategies for the treatment of atrial fibrillation (AF) are associated with several potential complications. During electro-anatomic mapping of the left atrium (LA) before ablation, the ablation catheter was entrapped in the right inferior pulmonary vein (RIPV). After multiple unsuccessful gentle tractions, stronger maneuvers with rotation of the catheter slowly allowed its retrieval. Examination of the catheter showed a thin, translucent membrane covering its tip, suggesting complete stripping of a vein branch. Occlusion of the superior branch of the RIPV was confirmed by LA angiogram. During the following days, no pericardial effusion was noted, but the patient complained of light chest pain and mild hemoptysis, spontaneously resolving within 48 h. This case shows that catheter entrapment and mechanical disruption of a PV branch can be a rare potential complication of AF ablation. In this case, the outcome was spontaneously favorable and symptoms only included transient mild hemoptysis.

Persistent iatrogenic atrial septal defect after a single-puncture, double-transseptal approach for pulmonary vein isolation using a remote robotic navigation system: results from a prospective study

Persistent iatrogenic atrial septal defect (iASD) after transseptal puncture for pulmonary vein isolation (PVI) has been described recently as a complication of PVI. No data exists evaluating systematically the incidence and clinical implications of iASDs after PVI using a remote robotic navigation system (RNS) with sheaths with a distinct larger outer diameter. In this prospective study, 40 patients with either paroxysmal (n = 22, 55%) or persistent symptomatic atrial fibrillation were treated with circumferential PVI using an RNS. In all patients, a single-puncture, double-transseptal approach was used to access the left atrium. Transoesophageal echocardiography was performed before and the day after PVI as well as after a 3 and 6 months follow-up (FU). The day after ablation an iASD was detected in 38 of 40 (95%) patients with a mean diameter of 3.45 +/- 1.5 mm. At 6-month FU, the iASDs were closed in 30 of 39 (78.9%) patients. During the 6-month FU period, no patient died or suffered from cerebral or cardiac embolism. After a single-puncture, double-transseptal approach for PVI using the RNS, iASDs show a high spontaneous closure rate of 78.9% after a 6-month FU period. Persistent iASDs following PVI with the RNS are not associated with an increased rate of paradoxical embolism or with relevant shunting.

The State of the Art in Pulmonary Vein Stenosis -Diagnosis & Treatment.

Pulmonary vein stenosis is a rare but serious complication of pulmonary vein isolation to treat atrial fibrillation. Pulmonary vein angioplasty/stenting has emerged as the treatment of choice for significantly stenotic veins. Guidelines for post ablation evaluation of the pulmonary veins, including the timing and method of surveillance for possible stenosis, the criteria for intervention, the technical aspects of intervention, and finally the surveillance post intervention, are still being developed. The relatively high rate of restenosis after intervention in a subset of patients remains a great challenge. A better understanding of the pathophysiology underlying this syndrome is needed to appropriately answer many of the remaining questions. The goal of this manuscript is to describe what has been learned about this complication and its treatment from a relatively large experience in a single institution over the past decade, and provide a comprehensive review of the existing literature in order to shed as much light on the subject as is possible, while at the same time exposing the areas that need further study.

Safe and Effective Ablation of Atrial Fibrillation: Importance of Esophageal Temperature Monitoring to Avoid Periesophageal Nerve Injury as a Complication of Pulmonary Vein Isolation

Catheter ablation on the left atrial posterior wall has been reported to potentially damage the esophagus or periesophageal vagal nerve. The aim of this study was to evaluate the efficacy of esophageal temperature monitoring (ETM) in preventing esophageal or periesophageal vagal nerve injury in patients with atrial fibrillation (AF) undergoing pulmonary vein (PV) isolation. This study included 359 patients with drug-refractory AF who underwent extensive PV isolation. The first 152 patients were treated without ETM (non-ETM) and the last 207 with ETM. In the ETM group, the esophageal temperature (ET) was measured with a deflectable temperature probe that was placed close to the ablation electrode, and the radiofrequency energy applications were stopped when the ET reached 42 degrees C. In all patients in the ETM group, the ET increased to 42 degrees C in at least one site by 28 +/- 14 seconds, mostly along the right side of the left PVs, especially near the left inferior PV. Less energy (6.3 +/- 1.9 x 10(4) J) was required for PV isolation in the ETM group than that in the non-ETM (6.8 +/- 1.9 x10(4) J, P = 0.03). Gastric hypomotility owing to periesophageal nerve damage was observed in three patients in the non-ETM group, but in none in the ETM (P = 0.02). The recurrence rates of AF did not differ between the two groups (non-ETM, 29%; ETM, 27%). Titration of the duration of the ablation energy delivery while monitoring the ET could prevent periesophageal nerve injury due to the AF ablation, without decreasing the success rate of maintaining sinus rhythm.

Comparison of Stent Versus Balloon Angioplasty for Pulmonary Vein Stenosis Complicating Pulmonary Vein Isolation

Pulmonary vein stenosis (PVS) is a rare but significant complication of pulmonary vein isolation (PVI). Dilation and stent angioplasty have been described but not compared. All percutaneous interventions for PVS complicating PVI between December 2000 and March 2007 were reviewed. Acute success, defined as post-intervention stenosis <or=30%, and long-term outcome of dilation versus stent angioplasty were compared. Freedom from restenosis was defined as freedom from repeat intervention. Overall outcome for all interventions was examined. We studied 34 patients with 55 stenotic veins followed for a mean of 25 months. Dilation was performed in 39 veins and stenting in 40 veins (16 primarily, 24 after dilation restenosis). Acute success and restenosis rates were 42% and 72% for dilation versus 95% (P < 0.001) and 33% for stenting. Time to restenosis was greater for stent angioplasty (P = 0.003). Stents >or=10 mm in diameter had lower restenosis than smaller stents. Risk factors for restenosis included small reference vessel diameter and longer time from PVI to intervention for PVS. All but two patients experienced improvement (n = 10) or resolution of symptoms (n = 22). The mean percent stenosis decreased from 82% to 21% for the entire cohort and mean flow to the lung quadrant increased from 10% to 17%. Stent angioplasty results in less restenosis than dilation, particularly for stents >or=10 mm. Early referral may improve long-term patency by minimizing reference vessel atrophy. Most patients with PVS post-PVI can be improved symptomatically with catheter intervention.

Minimally Invasive Surgical Release of Entrapped Mapping Catheter in the Mitral Valve

Two cases of catheter entrapment in the mitral valve, which is a rare complication of pulmonary vein isolation, were successfully treated via robot-assisted minimally invasive surgery.