A zero-exchange approach for left atrial access in pulmonary vein isolation with pulsed field ablation.

INTRODUCTION: Pulsed field ablation (PFA) has emerged as an innovative technique for pulmonary vein isolation (PVI). Typically, a transeptal puncture (TSP) with a standard sheath precedes a switch to the larger diameter sheath in the left atrium. This study aimed to describe the safety and feasibility of direct TSP using the large diameter Faradrive sheath before performing PVI with PFA. METHODS: We prospectively enrolled 166 consecutive patients with paroxysmal or persistent atrial fibrillation (AF) undergoing PVI with PFA at our institution. TSP was performed in all cases with transesophageal echocardiography guidance, using the Faradrive sheath and a 98 cm matched Brockenbrough needle. The primary endpoint was the occurrence of pericardial tamponade during or within the first 48 h after the procedure. The secondary endpoint was the occurrence of any major complication. RESULTS: All 166 patients were included into the final analysis (44% female): 64% of patients had paroxysmal AF and 36% persistent AF (68 ± 11 years old, median CHA2DS2Vasc Score 3, median left atrial volume index 31). The median duration of the procedure was 60 min, median time to TSP was 15 min, and the median fluoroscopy dose was 595 cGy × cm2. The primary endpoint occurred in one patient: a non-TSP related pericardial tamponade, which was managed with pericardial puncture. CONCLUSION: Direct TSP with skipping sheath exchange using the large diameter Faradrive sheath for PVI with PFA was safe, feasible, and reduced costs in all patients. Large scale studies and registries are needed to verify this workflow.

Unipolar-voltage-based evaluation of left atrial tissue properties and ablation outcome in patients with atrial fibrillation.

AIMS: The relationship between local unipolar voltage (UV) in the pulmonary vein (PV)-ostia and left atrial wall thickness (LAWT) and the utility of these parameters as indices of outcome after atrial fibrillation (AF) ablation remain unclear. METHODS AND RESULTS: Two-hundred seventy-two AF patients who underwent AF ablation were enrolled. Unipolar voltage of PV-ostia was measured using a CARTO system, and LAWT was measured using computed tomography. The primary endpoint was atrial tachyarrhythmia (ATA) recurrence including AF. The ATA recurrence was documented in 74 patients (ATA-Rec group). The UV and LAWT of the bilateral superior PV roof to posterior and around the right-inferior PV in the ATA-Rec group were significantly greater than in patients without ATA recurrence (ATA-Free group) (P < 0.001). The UV had a strong positive correlation with LAWT (R2 = 0.446, P < 0.001). The UV 2.7 mV and the corresponding LAWT 1.6 mm were determined as the cut-off values for ATA recurrence (P < 0.001, respectively). Multisite LA high UV (HUV, ≥4 areas of >2.7 mV) or multisite LA wall thickening (≥5 areas of >1.6 mm), defined as LA hypertrophy (LAH), was related to higher ATA recurrence. Among 92 LAH patients, 66 had HUV (LAH-HUV) and the remaining 26 had low UV (LAH-LUV), characterized by history of non-paroxysmal AF and heart failure, reduced LV ejection fraction, or enlarged LA. In addition, LAH-LUV showed the worst ablation outcome, followed by LAH-HUV and No LAH (log-rank P < 0.001). CONCLUSION: Combining UV and LAWT enables us to stratify recurrence risk and suggest a tailored ablation strategy according to LA tissue properties.

Impact of cryoballoon application abortion due to phrenic nerve injury on reconnection rates: a YETI subgroup analysis.

AIMS: Cryoballoon (CB)-based pulmonary vein isolation (PVI) is an effective treatment for atrial fibrillation (AF). The most frequent complication during CB-based PVI is right-sided phrenic nerve injury (PNI) which is leading to premature abortion of the freeze cycle. Here, we analysed reconnection rates after CB-based PVI and PNI in a large-scale population during repeat procedures. METHODS AND RESULTS: In the YETI registry, a total of 17 356 patients underwent CB-based PVI in 33 centres, and 731 (4.2%) patients experienced PNI. A total of 111/731 (15.2%) patients received a repeat procedure for treatment of recurrent AF. In 94/111 (84.7%) patients data on repeat procedures were available. A total of 89/94 (94.7%) index pulmonary veins (PVs) have been isolated during the initial PVI. During repeat procedures, 22 (24.7%) of initially isolated index PVs showed reconnection. The use of a double stop technique did non influence the PV reconnection rate (P = 0.464). The time to PNI was 140.5 ± 45.1 s in patients with persistent PVI and 133.5 ± 53.8 s in patients with reconnection (P = 0.559). No differences were noted between the two populations in terms of CB temperature at the time of PNI (P = 0.362). The only parameter associated with isolation durability was CB temperature after 30 s of freezing. The PV reconnection did not influence the time to AF recurrence. CONCLUSION: In patients with cryoballon application abortion due to PNI, a high rate of persistent PVI rate was found at repeat procedures. Our data may help to identify the optimal dosing protocol in CB-based PVI procedures. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03645577?term=YETI&cntry=DE&draw=2&rank=1 ClinicalTrials.gov Identifier: NCT03645577.

Case report: "A healthy woman with exertional dyspnea: Indication of a pacemaker or not?"

The selection of patients with chronotropic incompetence (CI) for cardiac pacing therapy remains challenging. Here, we present a case of a 40-year-old woman with severe exertional dyspnea. The exercise test revealed a blunted increase in the heart rate (HR) (maximum of 110 bpm). Her exercise capacity significantly improved under atrial stimulation at 170 bpm using a temporary pacing lead. Therefore, we implanted a rate-adaptive dual-chamber pacemaker with a blended sensor. During follow-up exercise capacity normalized, and she had no residual exertional dyspnea at 6 months. This case highlights the potential value for individual assessments of CI to identify clear indications for pacemaker implantation.

Improving Valvular Pathologies and Ventricular Dysfunction Diagnostic Efficiency Using Combined Auscultation and Electrocardiography Data: A Multimodal AI Approach.

Simple sensor-based procedures, including auscultation and electrocardiography (ECG), can facilitate early diagnosis of valvular diseases, resulting in timely treatment. This study assessed the impact of combining these sensor-based procedures with machine learning on diagnosing valvular abnormalities and ventricular dysfunction. Data from auscultation at three distinct locations and 12-lead ECGs were collected from 1052 patients undergoing echocardiography. An independent cohort of 103 patients was used for clinical validation. These patients were screened for severe aortic stenosis (AS), severe mitral regurgitation (MR), and left ventricular dysfunction (LVD) with ejection fractions ≤ 40%. Optimal neural networks were identified by a fourfold cross-validation training process using heart sounds and various ECG leads, and their outputs were combined using a stacking technique. This composite sensor model had high diagnostic efficiency (area under the receiver operating characteristic curve (AUC) values: AS, 0.93; MR, 0.80; LVD, 0.75). Notably, the contribution of individual sensors to disease detection was found to be disease-specific, underscoring the synergistic potential of the sensor fusion approach. Thus, machine learning models that integrate auscultation and ECG can efficiently detect conditions typically diagnosed via imaging. Moreover, this study highlights the potential of multimodal artificial intelligence applications.

Bipolar ablation of therapy-refractory ventricular arrhythmias: application of a dedicated approach.

AIMS: Bipolar radiofrequency ablation (B-RFA) has been reported as a bail-out strategy for the treatment of therapy refractory ventricular arrhythmias (VA). Currently, existing setups have not been standardized for B-RFA, while the impact of conventional B-RFA approaches on lesion formation remains unclear. METHODS AND RESULTS: (i) In a multicentre observational study, patients undergoing B-RFA for previously therapy-refractory VA using a dedicated B-RFA setup were retrospectively analysed. (ii) Additionally, in an ex vivo model lesion formation during B-RFA was evaluated using porcine hearts. In a total of 26 procedures (24 patients), acute success was achieved in all 14 ventricular tachycardia (VT) procedures and 7/12 procedures with premature ventricular contractions (PVC), with major complications occurring in 1 procedure (atrioventricular block). During a median follow-up of 211 days in 21 patients, 6/11 patients (VT) and 5/10 patients (PVC) remained arrhythmia-free. Lesion formation in the ex vivo model during energy titration from 30 to 50 W led to similar lesion volumes compared with initial high-power 50 W B-RFA. Lesion size significantly increased when combining sequential unipolar and B-RFA (1429 mm3 vs. titration 501 mm3 vs. B-RFA 50 W 423 mm3, P < 0.001), an approach used in overall 58% of procedures and more frequently applied in procedures without VA recurrence (92% vs. 36%, P = 0.009). Adipose tissue severely limited lesion formation during B-RFA. CONCLUSION: Using a dedicated device for B-RFA for therapy-refractory VA appears feasible and safe. While some patients need repeat ablation, success rates were encouraging. Sequential unipolar and B-RFA may be favourable for lesion formation.

Association of adipocytokines serum levels with left atrial thrombus formation in atrial fibrillation patients on oral anticoagulation (Alert) - A cross-sectional study.

BACKGROUND AND AIMS: Oral anticoagulation is effective for stroke prevention in atrial fibrillation (AF). However, strokes may still occur in high-risk individuals. We conducted a prospective trial to assess the association between adipocytokine serum levels and surrogate parameters for thromboembolic events. METHODS AND RESULTS: In this cross-sectional multicenter trial, we enrolled 189 patients with AF who were on oral anticoagulation. The primary endpoint was defined as either the presence of spontaneous echo contrast (SEC), a left atrial appendage (LAA), or a left atrial (LA) thrombus on transesophageal echocardiography. We investigated the association of adipocytokine serum levels with the combined endpoint using logistic regression analysis. Forty-eight individuals (25%) were assigned to group 1 (G1) due to the occurrence of at least one of the components of the combined endpoint (41 [21.7%] SEC, 3 [1.6%] LA thrombus, 13 [6.9%] LAA thrombus), whereas the remaining patients formed group 2 (G2). The BMI, logarithmized (loge) leptin (G1: 2.0 ± 1.3 µg/ml, G2: 2.0 ± 1.1 µg/ml, p = 0.746) and visfatin serum levels (G1: 3.4 ± 0.3 ng/ml, G2: 3.4 ± 0.5 ng/ml, p = 0.900) did not significantly differ between the groups. Conversely, logarithmized adiponectin (G1: 3.3 ± 0.6 ng/ml, G2: 3.1 ± 0.7 ng/ml, p = 0.036) and resistin levels (G1: 1.8 ± 0.5 ng/ml, G2: 1.6 ± 0.5 ng/ml, p = 0.009) were higher in patients with the primary endpoint. Multivariate logistic regression analysis using a score that combined the individual adiponectin and resistin values in each patient corroborated this association. CONCLUSIONS: Our results suggest that adiponectin and resistin may act as potential biomarkers to identify individuals with AF who are at high thromboembolic risk.

Disease-associated HCN4 V759I variant is not sufficient to impair cardiac pacemaking.

The hyperpolarization-activated cation current If is a key determinant for cardiac pacemaker activity. It is conducted by subunits of the hyperpolarization-activated cyclic nucleotide-gated (HCN) channel family, of which HCN4 is predominant in mammalian heart. Both loss-of-function and gain-of-function mutations of the HCN4 gene are associated with sinus node dysfunction in humans; however, their functional impact is not fully understood yet. Here, we sought to characterize a HCN4 V759I variant detected in a patient with a family history of sick sinus syndrome. The genomic analysis yielded a mono-allelic HCN4 V759I variant in a 49-year-old woman presenting with a family history of sick sinus syndrome. This HCN4 variant was previously classified as putatively pathogenic because genetically linked to sudden infant death syndrome and malignant epilepsy. However, detailed electrophysiological and cell biological characterization of HCN4 V759I in Xenopus laevis oocytes and embryonic rat cardiomyocytes, respectively, did not reveal any obvious abnormality. Voltage dependence and kinetics of mutant channel activation, modulation of cAMP-gating by the neuronal HCN channel auxiliary subunit PEX5R, and cell surface expression were indistinguishable from wild-type HCN4. In good agreement, the clinically likewise affected mother of the patient does not exhibit the reported HCN4 variance. HCN4 V759I resembles an innocuous genetic HCN channel variant, which is not sufficient to disturb cardiac pacemaking. Once more, our work emphasizes the importance of careful functional interpretation of genetic findings not only in the context of hereditary cardiac arrhythmias.

One-Year Course of Periprocedural Anticoagulation in Atrial Fibrillation Ablation: Results of a German Nationwide Survey.

INTRODUCTION: Periprocedural oral anticoagulation (OAC) strategies for atrial fibrillation (AF) ablation procedures are changing rapidly. OBJECTIVE: To assess the management and course of periprocedural OAC for AF ablation procedures in experienced electrophysiology (EP) centers in Germany over the last 12 months. METHODS: The data are based on an electronic questionnaire, which was sent to 35 experienced EP centers in September 2018 and then exactly 1 year later. Participants provided information on their periprocedural OAC management, the handling with dual therapy (OAC plus single antiplatelet therapy), the availability of specific antidotes, the transseptal puncture approach, and noteworthy complications. RESULTS: Responses were received from all 35 centers and represent 10,010 AF ablation procedures annually. In 2018, the administration of vitamin K antagonist (VKA) was continued throughout the procedure at all centers (100%). In contrast, the majority of centers used minimally interrupted periprocedural non-vitamin K antagonist oral anticoagulants (NOAC) (54.3%), 13 centers (37.2%) completely interrupted NOAC, and only 3 centers (8.5%) continued NOAC throughout the procedure. At the 1-year follow-up survey, 32 centers were found to have continued their previous strategy of periprocedural OAC and 3 changed from a minimally interrupted to a continued NOAC strategy. Of note, 30 centers (85.7%) performed transseptal puncture fluoroscopically without additional cardiac imaging. In the setting of uninterrupted periprocedural OAC management, no relevant complications were noted. CONCLUSION: Our survey shows marked heterogeneous periprocedural OAC management at experienced EP centers in Germany. Whereas continuation of VKA has already been integrated into clinical practice, the majority of centers still use a minimally interrupted NOAC strategy.

Avoiding inappropriate therapy of single-lead implantable cardioverter-defibrillator by using atrial-sensing electrodes.

INTRODUCTION: The single-chamber implantable cardioverter-defibrillator (ICD) can be associated with more frequent inappropriate therapies compared with dual-chamber ICDs, when they are accompanied by a simpler implantation procedure. The aim of this study was to investigate whether the use of a single-lead ICD system with atrial-sensing electrodes results in a reduction of inappropriate ICD therapy. METHODS AND RESULTS: The study population consisted of 212 consecutive patients, who underwent primary prophylactic single-lead ICD implantation at our institute. A ventricular lead with atrial-sensing electrodes was implanted in 77 patients (36%; Group-VDD) and a ventricular lead without atrial-sensing electrodes was implanted in 135 patients (64%; Group-VVI). Procedural and follow-up data were collected in a prospective registry. A higher prevalence of atrial fibrillation was present in Group-VDD. There were no other significant differences in patient baseline characteristics (age, sex, and other comorbidities) or follow-up period between the two groups. The operative parameters including fluoroscopic burden showed no significant differences between Group-VDD and Group-VVI. During a mean follow-up period of 697 ± 392 days, 26 patients (12%) experienced appropriate ICD therapies and 13 patients (6%) suffered inappropriate ICD therapies. The incidence of inappropriate ICD therapies in Group-VDD was significantly lower as compared to that of Group-VVI (1/77 [1%] vs 12/135 [9%]; log-rank, P = 0.028). The incidence of appropriate ICD therapies and the occurrence of device-related complications showed no significant difference between the two groups. CONCLUSION: Single-lead ICD with atrial-sensing electrodes shows a lower incidence of inappropriate ICD therapy compared with the absence of atrial-sensing electrodes, without additional operative burden or increased complications.

Higher contact force, energy setting, and impedance rise during radiofrequency ablation predicts charring: New insights from contact force-guided in vivo ablation.

INTRODUCTION: Higher contact force (CF) theoretically increases the risk of blood charring, diminishing lesion formation. We aimed to investigate the relationship between CF, impedance change, and char formation during pulmonary vein isolation (PVI). METHODS: CF was assessed during PVI in 65 patients. Radiofrequency ablation (RFA) with power-controlled mode was applied in the point-by-point manner. The RFA were divided into five groups: group A (CF < 10 g), group B (10 g ≤ CF < 20 g), group C (20 g ≤ CF < 30 g), group D (30 g ≤ CF < 40 g), and group E (CF ≥ 40 g). Gradual impedance rise (gIR) was defined as >5 Ω increase during each 10-second period of RFA. Catheter tip was assessed for charring during, and at the end of each procedure. RESULTS: In total, 2,064 applications were analyzed. During 0-10 seconds, impedance was significantly decreased in groups with higher CF (P < 0.05). During 10-20 seconds, an impedance decrease was not significantly different among the five groups. During 20-30 seconds, mean impedance increased in group E. A gIR was noted at least once during RFA in 63 patients (97%). The incidence of gIR during RFA after 20 seconds was significantly higher in groups D and E (77/504 [15.3%] vs. 90/1560 [5.8%], P < 0.001). Charring occurred in 8 of 65 (12%) patients. A gIR after 20 seconds was significantly associated with a higher incidence of macroscopic charring (6/20 [30%] vs. 2/45 [4%], P < 0.01). CONCLUSIONS: gIR was noted with higher applied CFs after 20 seconds of RFA. This impedance rise may be avoided by keeping the applied CF under 26.9 g with negative predictive value of 95%. Our data suggested that gIR may be related to the incidence of charring.

Association of left atrial low-voltage area and thromboembolic risk in patients with atrial fibrillation.

Aims: Atrial fibrillation (AF) is associated with thromboembolic events. Currently, the CHA2DS2-VASc score is recommended for thromboembolic risk stratification in non-valvular AF patients. However, recent data suggested a potential role of atrial remodelling on thromboembolism. This study aimed to assess the association between left atrial low-voltage area (LVA) and history of clinical manifest as well as subclinical silent cerebral ischaemia (SCI) in AF patients. Methods and results: Two-hundred patients [64 ± 10.5 years, 75 women (37.5%)] with symptomatic paroxysmal (n = 88, 44%) or persistent AF undergoing pulmonary vein isolation (PVI) were prospectively enrolled. Left atrial LVA (bipolar voltage < 0.5mV) was evaluated by intra-procedural mapping (>300 points per patient) during sinus rhythm. Cerebral delayed-enhancement magnetic resonance imaging was performed after PVI for detection of pre-existing procedural-independent SCI. Over all, 17 patients (8.5%) had previous history of stroke. Pre-existing SCIs were detected in 135 patients (67.5%). Patients with previous stroke (4.0 ± 1.5 vs. 2.1 ± 1.3, P < 0.0001) and pre-existing SCI (2.7 ± 1.3 vs. 1.5 ± 1.4, P < 0.0001) had a significantly higher CHA2DS2-VASc score. LVA was significantly larger in patients with previous stroke (12.5 ± 8.5% vs. 3.4 ± 5.4%, P < 0.0001) as well as pre-existing SCI (5.8 ± 6.9% vs. 0.8 ± 1.7%, P < 0.0001). Multivariate regression analysis revealed that LVA was independently associated with the presence of SCI [hazard ratio (HR) per 1% LVA 1.13 (1.06-1.22), P = 0.0003] and history of stroke [HR per 1% LVA 1.36 (1.19-1.60), P < 0.0001] after adjustment of CHA2DS2-VASc score. Conclusion: Left atrial LVA is associated with history of stroke and SCI in patients with non-valvular AF and might improve thromboembolic risk stratification after confirmation of its predictive value in future studies.

Sympathetic and Parasympathetic Coactivation Induces Perturbed Heart Rate Dynamics in Patients with Paroxysmal Atrial Fibrillation.

BACKGROUND Recent evidence indicates that sympathetic/parasympathetic coactivation (CoA) is causally linked to changes in heart rate (HR) dynamics. Whether this is relevant for patients with atrial fibrillation (AF) is unknown. MATERIAL AND METHODS In patients with paroxysmal AF (n=26) and age-matched controls, (n=10) we investigated basal autonomic outflow and HR dynamics during separate sympathetic (cold hand immersion) and parasympathetic activation (O2-inhalation), as well as during CoA (cold face test). In an additional cohort (n=7), HR response was assessed before and after catheter-based pulmonary vein isolation (PVI). Ultra-high-density endocardial mapping was performed in patients (n=6) before and after CoA. RESULTS Sympathetic activation increased (control: 74±3 vs. 77±3 bpm, p=0.0098; AF: 60±2 vs. 64±2 bpm, p=0.0076) and parasympathetic activation decreased HR (control: 71±3 vs. 69±3 bpm, p=0.0547; AF: 60±1 vs. 58±2 bpm, p<0.0009), while CoA induced a paradoxical HR increase in patients with AF (control: 73±3 vs. 71±3 bpm, p=0.084; AF: 59±2 vs. 61±2 bpm, p=0.0006), which was abolished after PVI. Non-linear parameters of HR variability (SD1) were impaired during coactivation in patients with AF (control: 61±7 vs. 69±6 ms, p=0.042, AF: 44±32 vs. 32±5 ms, p=0.3929). CoA was associated with a shift of the earliest activation site (18±4 mm) of the sinoatrial nodal region, as documented by ultra-high-density mapping (3442±343 points per map). CONCLUSIONS CoA perturbs HR dynamics and shifts the site of earliest endocardial activation in patients with paroxysmal AF. This effect is abolished by PVI, supporting the value of emerging methods targeting the intrinsic cardiac autonomic nervous system to treat AF. CoA might be a valuable tool to assess cardiac autonomic function in a clinical setting.

Conversion of Atrial Fibrillation after Cardiosurgical Procedures by Vernakalant® as an Atrial Repolarization Delaying Agent (ARDA).

BACKGROUND: Postoperative, new-onset atrial fibrillation (POAF) is one of the most common complications after cardiosurgical procedures. Vernakalant has been reported to be effective in the conversion of POAF. The aim of this study was to evaluate the efficacy and safety of vernakalant for atrial fibrillation after cardiac operations, and to investigate predictors for the success of vernakalant treatment. Patients and Methods: Post-cardiac surgery patients with new-onset of atrial fibrillation (AF) were consecutively enrolled in this study. Demographic data as well as intraoperative and postoperative parameters were analyzed. Vernakalant administration was primarily started 5.5 hours after new-onset POAF: 3 mg/kg intravenously over 10 min, and in case of non-conversion, a second dose of 2 mg/kg intravenously over 10 min. Results: 129 consecutive patients (70.2 ± 9.1 years) were included: 61 patients with coronary artery bypass graft (CABG) surgery, 49 patients with isolated valve procedures, and 19 patients with combined procedures (CABG and valve). Conversion in sinus rhythm was achieved after the first vernakalant dose in 57 patients (44%), and after the second dose in 41 patients (32%). The mean time to conversion was 13.7 ± 14.1 min. The patients receiving valve procedures depicted a significantly lower conversion rate. The following variables lowered conversion rate: no preoperative beta blocker, postoperative troponin levels >500 ng/L, and systolic blood pressure >140 mmHg. At the first follow-up, 92% of the converted patients showed sinus rhythm, while 80% of the non-responders showed sinus rhythm (P < .01). Conclusions: The POAF was effectively converted by vernakalant. The conversion rate of POAF after valve surgery was lower when compared to isolated CABG.

Effect of Sympatholytic Therapy on Circadian Cardiac Autonomic Activity in Non-Diabetic Chronic Kidney Disease.

Although beta-blockade itself is not a first choice for chronic kidney disease (CKD) patients, alpha-beta-blockers (ABB) do improve their prognoses. This study's aim was to evaluate the effect of beta-selective-blockers (BSB) and ABB on circadian cardiac autonomic activity in CKD patients.The study consisted of 496 non-diabetic individuals who underwent 24-hour Holter monitoring (149 CKD patients and 347 controls without CKD). Using heart rate variability analysis, we evaluated the proportion of NN50 and the high-frequency component (reflecting parasympathetic activity), and low- to high-frequency ratio (reflecting sympathovagal balance). These indices were evaluated by regression analysis incorporating gender, age, related comorbidities, and medications. BSB increased vagal activity only in the day-time and not the night-time in controls. In CKD patients, BSB was significantly related to higher vagal activity throughout the day and with lower sympathovagal balance at night. The night sympathovagal balance of CKD patients taking ABB was significantly higher than that of CKD patients taking BSB, which was the only significant difference between the effects of BSB and ABB.The sympatholytic therapy effect is different depending on CKD presence and whether patients are treated with BSB or ABB. In CKD patients without severe heart failure, BSB could be associated with higher parasympathetic activity and lower sympathovagal balance compared to ABB.

Persistent tachycardia within isolated pulmonary veins during atrial fibrillation ablation.

During circumferential pulmonary vein (PV) isolation for ongoing atrial fibrillation (AF), distinguishing passive conduction to the pulmonary vein (PV) from rapid PV arrhythmia in the isolated PV is difficult. Hence, the purpose of this study is to investigate both the feasibility of distinguishing the PV tachycardia after circumferential PV isolation and the electrophysiological characteristics of these tachycardia. Among 178 consecutive patients who underwent circumferential PV isolation during ongoing AF, fibrillatory PV converted to a regular cycle length PV tachycardia independent of the atrial rhythm (=independent PV tachycardia) in 13 PVs among 12 (7%) patients. We classified independent PV tachycardia according to 3 different atrial rhythms: sinus rhythm (type 1, n = 2), atrial tachycardia (type 2, n = 4), and AF (type 3, n = 6). independent PV tachycardia was observed in 3 right PV and 10 left PV (P = 0.0864). There were 10 mappable independent PV tachycardia, in which 8 were focal and 2 were macroreentrant tachycardia. i-PVT can be diagnosed in a small number of patients who underwent circumferential PV isolation during AF. The main mechanism or independent PV tachycardia was focal tachycardia mainly in the left PV.

Low Incidence of Esophageal Lesions After Pulmonary Vein Isolation Using Contact-Force Sensing Catheter Without Esophageal Temperature Probe.

Pulmonary vein isolation (PVI) is a cornerstone therapy for atrial fibrillation (AF). Although severe complications are rather rare, the development of an atrio-esophageal fistula (AEF) is a fatal complication with a very high mortality even after surgical treatment. The use of esophageal temperature probes (ETP) during PVI may protect the esophagus but it is still under debate since the ETP may also lead to esophageal lesions. The aim of this study was to evaluate the clinical safety of PVI using contact-force (CF) sensing catheter without esophageal temperature monitoring.We investigated 70 consecutive patients who underwent point-by-point PVI without usage of ETP and who underwent esophago-gastro-duodenoscopy (EGD) with detailed evaluation of the esophagus after the index PVI procedure. The operator attempted to keep CF within the 10-40 g range. The incidences of esophageal lesions (EDEL) detected by endoscopy were then analyzed.Two of 70 patients (2.9%) showed EDEL consisting of one longitudinal ulcer-like erythematous lesion with fibrin and a different one consisting of a round-shaped lesion surrounded by erythema and petechial hemorrhage. All EDEL healed within two weeks under high proton-pump inhibitor therapy without developing AEF as proven by a second EGD of the esophagus.Point-by-point PVI without usage of ETP showed a low incidence of EDEL (2.9%); atrio-esophageal fistula was absent. Further studies on the necessity of ETP under CF control are necessary.

One-Year Success Rate of Pulmonary Vein Isolation Using a Novel Irrigated Multipolar Mapping and Ablation Catheter With Reduced Power Settings.

The use of a novel irrigated multipolar ablation and mapping catheter for pulmonary vein isolation in patients with atrial fibrillation (AF) has demonstrated reasonable acute success rates and short procedure times, however, long-term outcome data are limited. The aim of this study was to analyze the long-term efficacy of this novel ablation system utilizing a reduced power setting for safety purposes.A total of 89 patients with paroxysmal (63 of 89 patients; 71%) or persistent AF underwent PVI with a reduced power setting of maximum 20 Watts (W) unipolar radiofrequency energy and 30 seconds in duration. In cases of persistent AF, atrial substrate ablation was performed additionally. Follow-up was based on outpatient clinic visits at 3, 6, and 12 months and included 5-day Holter ECGs. All of the 347 identified pulmonary veins were successfully isolated. Mean procedure times in PVI and PVI plus substrate ablation were 102 ± 25 minutes and 126 ± 32 minutes, respectively, applying a mean total radiofrequency time of 14 ± 6 minutes and 19 ± 9 minutes. Mean fluoroscopy time was 17 ± 8 minutes and 18 ± 6 minutes, respectively. Follow-up was available for all 89 patients. At one-year follow-up, 44 (70%) patients with paroxysmal AF and 11 (42%) patients with persistent AF remained in stable sinus rhythm after a singleprocedure and off antiarrhythmic drugs.The use of a novel irrigated multipolar ablation catheter with a reduced power setting is safe and feasible, and demonstrates a one-year success rate of 70% in paroxysmal AF and 42% in persistent AF.

Reduction of Fluoroscopic Exposure Using a New Fluoroscopy Integrating Technology in a 3D-Mapping System During Pulmonary Vein Isolation With a Circular Multipolar Irrigated Catheter.

Pulmonary vein isolation (PVI) is a cornerstone therapy in patients with atrial fibrillation (AF). With increasing numbers of PVI procedures, demand arises to reduce the cumulative fluoroscopic radiation exposure for both the physician and the patient. New technologies are emerging to address this issue. Here, we report our first experiences with a new fluoroscopy integrating technology in addition to a current 3D-mapping system. The new fluoroscopy integrating system (FIS) with 3D-mapping was used prospectively in 15 patients with AF. Control PVI cases (n = 37) were collected retrospectively as a complete series. Total procedure time (skin to skin), fluoroscopic time, and dose-area-product (DAP) data were analyzed. All PVI procedures were performed by one experienced physician using a commercially available circular multipolar irrigated ablation catheter. All PVI procedures were successfully undertaken without major complications. Baseline characteristics of the two groups showed no significant differences. In the group using the FIS, the fluoroscopic time and DAP were significantly reduced from 571 ± 187 seconds versus 1011 ± 527 seconds (P = 0.0029) and 4342 ± 2073 cGycm(2) versus 6208 ± 3314 cGycm(2) (P = 0.049), respectively. Mean procedure time was not significantly affected and was 114 ± 31 minutes versus 104 ± 24 minutes (P = 0.23) by the FIS.The use of the new FIS with the current 3D-mapping system enables a significant reduction of the total fluoroscopy time and DAP compared to the previous combination of 3D-mapping system plus normal fluoroscopy during PVI utilizing a circular multipolar irrigated ablation catheter. However, the concomitant total procedure time is not affected. Thus, the new system reduces the radiation exposure for both the physicians and patients.

Six-Year Clinical Outcomes After Catheter Ablation of Atrial Fibrillation in Patients With Impaired Left Ventricular Function.

INTRODUCTION: Long-term data after pulmonary vein isolation (PVI) in patients with impaired systolic left ventricular ejection fraction (LVEF) are sparse. This study assessed the outcomes in patients with atrial fibrillation (AF) and reduced LVEF treated with PVI after a median follow-up period of 6 years. METHODS AND RESULTS: Eighty-one patients with an LVEF≤45% were evaluated; however, 1 patient was lost to follow-up. In the remaining 80 patients (male: n = 68 (85%), median age 61.6 (54.8-67.5) years) with paroxysmal (n = 16, 20%), persistent (n = 37, 46.2%), and longstanding-persistent AF (LS-AF), catheter ablation of AF using radiofrequency and 3D mapping was performed. Follow-up included Holter monitoring or pacemaker/ICD interrogation to assess for arrhythmia recurrence and echocardiography to assess LVEF. Median follow-up was 72 (67-75) months. Death occurred in 21 patients. Single-procedure success rate was 35.1% and multiple-procedure success rate was 56.8% in the overall group. Baseline median LVEF (35% [28.5-40%]) significantly increased at 6-year follow-up (56.5% [40.0-60.0%], P < 0.01). In patients with single- or multiple-procedure ablation success, there was a higher improvement of LVEF (single procedure: 25% [15.0-35] vs. 10.0% [-1.0-20.0], P < 0.01; multiple procedures: 20.0% [15-34] vs. 5.0% [5.00-15.0]; P < 0.01). The single (43.8% vs. 40%, P = 0.96) and multiple procedure success rates (62.5% vs. 60%, P = 0.47) were comparable between patients with PAF and persistent AF and lowest in patients with LS-AF (single procedure success: 23.1%, multiple-procedure success: 47.8%). CONCLUSION: Single-procedure success rates after PVI during 6 years of follow-up were low. In patients with single- or multiple-procedure ablation success, a higher improvement of LVEF was observed.