Contact-force local impedance algorithm to guide effective pulmonary vein isolation in AF patients: 1-year outcome from an international multicenter clinical setting.

BACKGROUND: The combination of highly localized impedance (LI) and contact force (CF) may improve tissue characterization and lesion prediction during radiofrequency (RF) pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). OBJECTIVE: We report the outcomes of our acute and long-term clinical evaluation of CF-LI-guided PVI in consecutive AF ablation cases from an international multicenter clinical setting. METHODS: Three hundred twenty-four consecutive patients from 20 European centers undergoing RF catheter ablation with the Stablepoint™ catheter were enrolled in the CHARISMA registry. Of these, 275 had a minimum follow-up of 1 year and were included in the primary analysis. RESULTS: The mean procedure duration was 115 ± 47 min, and the mean fluoroscopy time was 9.9 ± 6 min. At the end of the procedures, all PVs had been successfully isolated in all study patients. Minor complications were reported in 12 patients (4.4%). At 1 year, 36 (13.1%) patients had had an AF recurrence, and freedom from antiarrhythmic drugs and AF recurrence was achieved in 228 (82.9%) patients. The recurrence rate was higher in patients with persistent AF (21/116, 18.1%) than in those with paroxysmal AF (15/159, 9.4%; p = 0.0459). On multivariate logistic analysis adjusted for baseline confounders, only time > 6 months from first diagnosis of AF to ablation (HR = 2.93, 95%CI 1.03 to 8.36, p = 0.0459) was independently associated with recurrences. CONCLUSION: An ablation strategy for PVI guided by CF-LI technology proved safe and effective and resulted in a low recurrence rate of AF over 1-year follow-up, irrespective of the underlying AF type. CLINICAL TRIAL REGISTRATION: Catheter Ablation of Arrhythmias with a High-Density Mapping System in Real-World Practice. (CHARISMA). URL: http://clinicaltrials.gov/ Identifier: NCT03793998.

Timing of cryoballoon pulmonary vein isolation to prevent atrial fibrillation recurrence.

BACKGROUND: The aims of this analysis were: to evaluate the impact of timing of ablation on the rate of atrial arrhythmias recurrence, verify if the timing of ablation impact differently in patients with paroxysmal and persistent AF. METHODS: Three thousand two hundred and five patients (60.5 ± 10 years, female 28.4%%, 78.8%% paroxysmal AF) were included in the analysis. All patients underwent only cryoballoon (CB) pulmonary vein (PV) isolation during the index procedure. RESULTS: The mean procedure time was 102.8 ± 50 min, with a mean fluoroscopy time of 26.3 ± 49 min. Acute PV isolation was achieved in 11760/11793 (99.7%) PVs. A total of 91 (2.8%) patients experienced a procedure-related complication. During the observation period 913/3205 (28.5%) patients had at least one atrial arrhythmias episode: 28% of patients with paroxysmal AF vs 33% of patients with persistent AF. In multivariate analysis, persistent AF together with time from symptomatic AF diagnosis to ablation, female sex, and ablation time showed to be significant predictors for AF recurrence. In particular, months from first symptomatic AF episode > 18 months was a significant predictor of AF recurrence (HR = 1.23, 95% CI = 1.03-1.46, p = 0.020). In patients with paroxysmal AF, the multivariate analysis confirmed that months from first symptomatic AF episode > 18 month was an independent predictor of AF recurrence together with age > 62 years and female sex. In patients with persistent AF, the time from persistent AF showed to be significant predictor for AF recurrence. CONCLUSIONS: In this multicenter analysis, time from first symptomatic AF episode > 18 months was a significant predictor of AF recurrence after CB PV isolation.

Safety and efficacy of cryoablation for atrial fibrillation in young patients: A multicenter experience in the 1STOP project.

BACKGROUND: Atrial fibrillation (AF) is an uncommon arrhythmia in young adults without structural heart disease, and cryoballoon pulmonary vein isolation (CB-PVI) is an important therapeutic strategy for rhythm control in patients with drug-refractory AF. The aim of this analysis was to evaluate efficacy and safety of CB-PVI in a large cohort of young patients in comparison with middle-aged adults in a real-world setting. METHODS: From 2012 to 2020, a total of 3033 patients with AF underwent CB-PVI and were followed prospectively in the framework of the 1STOP Clinical Service project, involving 34 Italian centers. Out of 3033 total 1STOP project subjects, a subgroup of 1318 patients were defined which included a YOUNG group (age ≤ 45 years; n = 368) and a MIDDLE-AGED group (age 60-65 years; n = 950). RESULTS: The acute success rate of PVI did not differ between the two cohorts (99.9 ± 1.3% vs. 99.8 ± 3.2%, p = 0.415). There was no difference in procedural characteristics, and periprocedural complication rates were similar among the two cohort (1.9% vs. 2.3%, p = 0.646). The 12-month freedom from AF recurrence was 88.9% (95% confidence interval [CI]: 84.7-92.0) in the YOUNG cohort and 85.6% (95% CI: 82.9-88.0) in the MIDDLE-AGED group. At 36-month follow-up, freedom from AF recurrence was 72.4% (65.5%-78.2%) and 71.8% (67.7%-75.6%), respectively with no significant difference among groups (p = 0.550). CONCLUSION: CB-PVI had similar efficacy and safety in YOUNG and MIDDLE-AGED patients. Younger age did not affect acute procedural results, complication rate, or AF recurrence after a single procedure.

Role of CHA2DS2-VASc score in predicting atrial fibrillation recurrence in patients undergoing pulmonary vein isolation with cryoballoon ablation.

BACKGROUND: Pulmonary vein isolation by cryoablation (PVI-C) is a standard therapy for the treatment of atrial fibrillation (AF). The CHA2DS2-VASc score is a well-established predictor of AF-related stroke. Whether the CHA2DS2-VASc score can also be useful in predicting the long-term clinical outcomes following PVI-C is still unsettled. The aim of this analysis was to evaluate the role of the CHA2DS2-VASc score in predicting AF recurrence after PVI-C. METHODS: Patients with symptomatic AF underwent an index PVI-C. Data were collected prospectively in the framework of the 1STOP ClinicalService project. Patients were categorized into two groups: low risk (LR) and high risk (HR) based on CHA2DS2-VASc score (0-1 and ≥ 2, respectively). RESULTS: Out of 3313 patients, 1910 (57.6%) had a CHA2DS2-VASc score between 0 and 1, while 1403 (42.3%) had CHA2DS2-VASc > = 2. Patient characteristics were significantly different between the two cohorts, including age, sex, BMI, paroxysmal AF, history of stroke, diabetes, and ischemic cardiomyopathy. On the contrary, procedural times and acute complications were comparable. The 36-month freedom from AF after a single procedure was 72.5% (95% CI: 69.8-75.0) in the LR group and 65.9% (95% CI: 62.3-69.2) in the HR score group (HR: 1.26, 95% CI: 1.08-1.47, p = 0.001). After multivariate analysis, higher CHA2DS2-VASc score was still a significant predictor of the risk of AF recurrence (HR: 1.33; 1.10-1.60, p = 0.003). CONCLUSIONS: PVI-C is highly effective in the treatment of AF over the long term. A CHA2DS2-VASc score ≥ 2 is an independent predictor of AF recurrence during the follow-up and should be considered during the clinical management after the index procedure.

Second versus fourth generation of cryoballoon catheters: The 1STOP real-world multicenter experience.

BACKGROUND: It has been observed that the fourth-generation cryoballoon (CB4) ablation catheter increased the rate of acute real-time recordings of pulmonary vein isolation (PVI) during the ablation for the treatment of atrial fibrillation (AF). The aim of this analysis was to compare the long-term outcome results between patients treated with the CB4 and second-generation cryoballoon (CB2). METHODS: In total, 492 patients suffering from AF, underwent PVI ablation with either the CB2 or CB4 catheter within this examination of the 1STOP real-world Italian project and were included in the analysis. Specifically, 246 consecutive patients treated by CB4 were compared to 246 propensity-matched control patients who underwent PVI using CB2. RESULTS: When comparing the patient cohorts treated with CB2 versus CB4, acute success rate (99.6 ± 4.7% vs. 99.7 ± 3.6%, p = .949) and peri-procedural complications (3.7% vs.1.2%, p = .080) were similar in both groups, respectively. However, procedure time (100 vs.75 min, p < .001) and fluoroscopy duration (21 vs.17 min, p < .001) were all significantly lower in the CB4 treated patient cohort. At the 12-month follow-up, the freedom from AF recurrence after a 90-day blanking period was significant higher in the CB4 as compared with the CB2 group (93.3% vs.81.3%, p < .001). CONCLUSIONS: In summary, usage of the CB4 ablation catheter increased the rate of acute PVI recording capability and resulted in a higher rate of long-term PVI success, as demonstrated by the reduced rate of AF recurrence in comparison to the CB2 cohort at the 12-month follow-up period.

[Leadless pacemakers: results of a survey from implanter centers in the Lombardy region]. / Pacemaker leadless: risultati di una survey condotta nei centri impiantatori della Regione Lombardia.

BACKGROUND: Transvenous pacing is nowadays the cornerstone of interventional management of bradyarrhythmias. It is still associated, however, with significant complications, mostly related to indwelling transvenous leads or device pocket. In order to reduce these complications, leadless pacemakers have been recently introduced into clinical practice, but no guidelines are yet available to indicate who are those patients that might benefit the most and whether leadless pacing should be preferred in the old or young population. This survey aims to describe the use of leadless pacemaker devices in a real-world setting. METHODS: Eleven arrhythmia centers in the Lombardy region (out of a total of 17 participating centers) responded to the proposed questionnaire regarding patient characteristics and indications to leadless pacing. RESULTS: Out of a total of 411 patients undergoing leadless pacing during 4.2 ± 0.98 years, the median age was 77 years, with 0.18% of patients having less than 18 years, 29.9% 18-65 years, 34.3% 65-80 years and 35.6% >80 years. The most common indication was slow atrial fibrillation (49% of patients), followed by atrioventricular block and sinoatrial dysfunction. Two centers reported in-hospital complications. CONCLUSIONS: Leadless pacemakers proved to be a safe pacing strategy actually destined mostly to elderly patients.

When local impedance meets contact force: preliminary experience from the CHARISMA registry.

PURPOSE: Highly localized impedance (LI) measurements during atrial fibrillation (AF) ablation have emerged as a viable real-time indicator of tissue characteristics and the consequent durability of the lesions created. We investigated the impact of catheter-tissue contact force (CF) on LI behavior during pulmonary vein isolation (PVI). METHODS: Forty-five consecutive patients of the CHARISMA registry undergoing de novo AF radiofrequency (RF) catheter ablation with a novel open-irrigated-tip catheter endowed with CF and LI measurement capabilities (Stablepoint™ catheter, Boston Scientific) were included. RESULTS: A total of 2895 point-by-point RF applications were analyzed (RF delivery time (DT) = 8.7±4s, CF = 13 ±±8 g, LI drop = 23 ±±7 Ω). All PVs were successfully isolated in an overall procedure time of 118 ±±34 min (fluoroscopy time = 13 ±±8 min). The magnitude of LI drop weakly correlated with CF (r = 0.13, 95% confidence interval (CI): 0.09 to 0.16, p < 0.0001), whereas both CF and LI drop inversely correlated with DT (r = -0.26, 95%CI: -0.29 to -0.22, p < 0.0001 for CF; r = -0.36, 95%CI: -0.39 to -0.33, p < 0.0001 for LI). For each 10 g of CF, LI drop markedly increased from 22.4 ± 7 Ω to 24.0 ± 8 Ω at 5 to 25 g CF intervals (5-14 g of CF vs 15-24 g of CF, p < 0.0001), whereas it showed smooth transition over 25 g (24.8 ± 7Ω at ≥ 25 g CF intervals, p = 0.0606 vs 15-24 g of CF). No major complications occurred during the procedures or within 30 days. CONCLUSIONS: CF significantly affects LI drop and probable consequent lesion formation during RF PVI. The benefit of higher contact (> 25 g) between the catheter and the tissue appears to have less impact on LI drop. TRIAL REGISTRATION: Catheter Ablation of Arrhythmias With High Density Mapping System in the Real World Practice (CHARISMA). URL: http://clinicaltrials.gov/ Identifier: NCT03793998.

Reduction of admissions for urgent and elective pacemaker implant during the COVID-19 outbreak in Northern Italy.

AIMS: The coronavirus disease-19 (COVID-19) outbreak has been recently associated with lower hospitalization rates for acute coronary syndromes. Aim of the study was to investigate whether a similar behaviour is observed in admissions for urgent pacemaker implant. METHODS: This retrospective study included 1315 patients from 18 hospitals in Northern Italy with a high number of COVID-19 cases. Hospitalization rates for urgent pacemaker implant were compared between the following periods: 20 February to 20 April 2020 (case period); from 1 January to 19 February 2020 (intra-year control period); from 20 February to 20 April 2019 (inter-year control period). RESULTS: The incidence rate of urgent implants was 5.0/day in the case period, 6.0/day in the intra-year control period and 5.8/day in the inter-year control period. Incidence rate in the case period was significantly lower than both the intra-year [incidence rate ratio (IRR): 0.81, 95% CI 0.67-0.99, P = 0.040] and inter-year control periods (IRR: 0.79, 95% CI 0.66-0.95, P = 0.012); this reduction was highest after the national lockdown (IRR 0.68, 95% CI 0.52-0.91, P = 0.009). The prevalence of residents in rural areas undergoing urgent pacemaker implant was lower in the case period (36%) than in both the intra-year (47%, P = 0.03) and inter-year control periods (51%, P = 0.002). Elective pacemaker implants also decreased in the case period, with the incidence rate here being 3.5/day vs. 6.4/day in the intra-year (-45%) and 6.9/day in the inter-year period (-49%). CONCLUSION: Despite severe clinical patterns, the COVID-19 outbreak has negatively affected the population presentation to Emergency Departments for bradyarrhythmias requiring urgent pacemaker implant in Northern Italy. This mainly occurred after the national lockdown and concerned patients living in rural areas.

Contact-Force Guided Posterior Wall Isolation as an Adjunctive Ablation Strategy for Persistent Atrial Fibrillation.

BACKGROUND: The efficacy of posterior wall isolation (PWI) on top of pulmonary vein isolation (PVI) in patients affected by persistent atrial fibrillation (AF) is still controversial and little is known about the impact of contact-force (CF) technology. OBJECTIVE: In this retrospective study, we present our experience with PWI using CF sensing catheters and its efficacy and safety as an adjunctive ablation strategy on top of PVI for management of patients with persistent and longstanding persistent AF. METHODS: A total of 73 consecutive patients (20.5% female) affected by persistent atrial fibrillation (10.9% long-standing) underwent PWI as an adjunctive therapy to PVI using CF sensing catheters. Outcomes were reported as incidence of atrial arrhythmic recurrences (ARs) lasting >30 seconds at follow up and in addition, in patients provided with insertable cardiac monitors (ICM), as burden of AF or atrial tachycardias (AT) at relevant time points. RESULTS: PWI was successfully achieved in 65 (89.0%) patients. Two (2.7%) minor vascular procedural complications were observed. At 1 and 2-year follow-up, ARs free survival was observed in 80.5% and 64.1% of patients, respectively with 75.3% of patients off antiarrhythmic drugs at the last follow-up. Ten patients underwent repeat ablations during the follow-up. At multivariate analysis, early ARs within 3 months after procedure, were associated with a two-fold increased risk of late ARs at follow-up. Among patients provided with ICM, PWI on top of PVI was able to reduce the mean AT/AF burden of more than 50% compared with pre-ablation time, reporting very low levels (≤ 5%) over 2 years. CONCLUSIONS: In persistent atrial fibrillation, PWI on top of PVI using CF sensing catheters is safe and effective, providing great reduction of burden of ARs. Early ARs are associated with a greater risk of late recurrences.

Combined therapy with subcutaneous implantable cardiac defibrillator and leadless pacemaker in a patient with persistent left superior vena cava and mega coronary sinus: A challenging case for the best treatment.

In a patient requiring pacing and defibrillation therapy, but without superior venous access, combined therapy with S-ICD and leadless pacemaker could be the best solution. An appropriate programming of both devices represents the technical challenge in order to avoid inappropriate shocks due to leadless pacing oversensing.

Confirmation of Pulmonary Vein Isolation with High-Density Mapping: Comparison to Traditional Workflows.

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. Yet tools and techniques used for confirmation of PVI vary greatly, and it is unclear whether the use of any particular combination of tools and techniques provides greater sensitivity for identifying gaps periprocedurally. It has been suggested the use of a high-density mapping catheter, which enables simultaneous recording of adjacent bipolar EGMs in two directions, may provide improved sensitivity for gap identification. Anonymized, acute procedural data was prospectively collected in AF ablation cases utilizing various workflows for confirmation of PVI. Post-hoc analysis was performed to evaluate the incidence of gaps detected by different diagnostic catheter technologies, including a high-density mapping catheter and circular mapping catheters (CMCs), and common techniques such as pacing the ablation lines. A total of 139 cases were included across three subgroup analyses: 99 cases were included in an indirect comparison of three mapping catheter technologies, revealing gaps in 36.7%, 38.9%, and 81.8% of cases utilizing a 10-pole CMC, 20-pole CMC, and a high-density mapping catheter, respectively; a direct comparison of diagnostic catheter technologies in 18 cryoballoon ablation cases revealed residual gaps in 22.2% of patients identified by high-density mapping which were missed previously with the use of a 3.3F CMC; in 22 cases utilizing a technique of pacing the ablation lines, high-density mapping identified residual gaps in 68.2% of patients. This proof of concept analysis demonstrated that the use of a high-density catheter which records orthogonal bipoles simultaneously, appears to improve acute detection of gaps in PVI lines relative to other commonly utilized techniques and technologies. The long-term impact of ablating these concealed gaps remains unclear. Further study, including direct comparison of diagnostic catheter technologies in a randomized setting with long-term followup, is warranted.

Predictive role of early recurrence of atrial fibrillation after cryoballoon ablation.

AIMS: The aims of this study were to determine the rate and the predictors of early recurrences of atrial fibrillation (ERAF) after cryoballoon (CB) ablation and to evaluate whether ERAF correlate with the long-term outcome. METHODS AND RESULTS: Three thousand, six hundred, and eighty-one consecutive patients (59.9 ± 10.5 years, female 26.5%, and 74.3% paroxysmal AF) were included in the analysis. Atrial fibrillation recurrence, lasting at least 30 s, was collected during and after the 3-month blanking period. Three-hundred and sixteen patients (8.6%) (Group A) had ERAF during the blanking period, and 3365 patients (Group B) had no ERAF. Persistent AF and number of tested anti-arrhythmic drugs ≥2 resulted as significant predictors of ERAF. After a mean follow-up of 16.8 ± 16.4 months, 923/3681 (25%) patients had at least one AF recurrence. The observed freedom from AF recurrence, at 24-month follow-up from procedure, was 25.7% and 64.8% in Groups A and B, respectively (P < 0.001). ERAF, persistent AF, and number of tested anti-arrhythmic drugs ≥2 resulted as significant predictors of AF. In a propensity score matching, the logistic model showed that ERAF 1 month after ablation are the best predictor of long-term AF recurrence (P = 0.042). CONCLUSION: In patients undergoing CB ablation for AF, ERAF are rare and are a strong predictor of AF recurrence in the follow-up, above all when occur >30 days after the ablation.

Myotonic dystrophy type 1 and high ventricular vulnerability at the electrophysiological evaluation: ICD yes or not?

A significant number of sudden death (SD) is observed in myotonic dystrophy (DM1) despite pacemaker implantation and some consider the ICD to be the preferential device in patients with conduction disease. According to the latest guidelines, prophylactic ICD implantation in patients with neuromuscular disorder should follow the same recommendations of non-ischemic dilated cardiomyopathy, being reasonable when pacing is needed. We here report a case of DM1 patient who underwent ICD implantation even in the absence of conduction disturbances on ECG and ventricular dysfunction/fibrosis at cardiac magnetic resonance. The occurrence of syncope, non-sustained ventricular tachycardias at 24-Holter ECG monitoring and a family history of SD resulted associated with ventricular fibrillation inducibility at electrophysiological study, favouring ICD implantation. On our advice, DM1 patient with this association of SD risk factors should be targeted for ICD implantation.

Expert opinion on continuous rhythm monitoring of patients with atrial fibrillation for candidates or patients who have already undergone ablation.

BACKGROUND: Continuous monitoring by implantable loop recorder (ILR) can provide information relevant to rhythm control and oral anticoagulation (OAC) after atrial fibrillation (AF) ablation, but there is little agreement on patients' selection and appropriate management strategy. METHODS: An expert panel (EP) made up of eight Italian electrophysiologists with expertise in AF ablation, gathered to define an algorithm to guide continuous rhythm monitoring in AF patients who have undergone ablation. The process included a review of the current literature and two EP face-to-face meetings. Between the two meetings, an on-line survey was sent to 50 Italian electrophysiologists practicing AF ablation. Agreement level was considered reached when ≥70% of respondents agreed or were neutral. RESULTS: Two algorithms were developed to define patients for whom the ILR would be suggested support for (OAC) therapy discontinuation and rhythm management after AF ablation. Thirty-three out of 50 physicians responded to on-line survey (66% response rate). Together with EP members the responders accounted for electrophysiology centers performing about 50% of total yearly Italian AF ablation procedures. Agreement level was reached at the first survey round on all the questions, so the algorithms were not further modified and re-tested. CONCLUSIONS: EP developed two algorithms for ECG monitoring to guide OAC therapy discontinuation and rhythm management after AF ablation. These suggestions, validated by wide feedback and consensus of physicians performing AF ablations, might support the decision on the choice and the use of ECG monitoring techniques, based on specific patient characteristics.

Cryoballoon Ablation in Patients With Paroxysmal Atrial Fibrillation: An Evaluation of Cohorts With and Without Structural Heart Disease.

BACKGROUND: Pulmonary vein isolation (PVI) is the most widely adopted strategy for paroxysmal atrial fibrillation (PAF) ablation. Limited evidence on acute results and late outcomes of cryoballoon (CB)-PVI in patients with structural heart disease (SHD) exist. The aim of this analysis was to compare acute procedural results and the 1-year recurrence rate of a single CB-PVI procedure in a PAF population with and without SHD. METHOD: From April 2012 to May 2017, a total of 2,031 patients with AF underwent CB-PVI and were followed prospectively in the framework of the One Shot TO Pulmonary vein isolation (1STOP) ClinicalService project, involving 36 Italian cardiology centres. We identified patients with SHD according to criteria proposed by current ESC guidelines: left ventricular (LV) systolic or diastolic dysfunction, long-standing hypertension with LV hypertrophy, and/or other structural heart disease. Data on procedural outcomes and long-term freedom from AF recurrence were evaluated. RESULTS: Our population consisted of 1,452 patients, of whom 282 (19.4%) were classified as having SHD. Compared to non-SHD patients, the SHD cohort was older (mean ± standard deviation, 62.9 ± 9.0 vs 58.2 ± 11.4 years; p < 0.001), was more frequently male (79.1% vs 69.8%; p < 0.002), had a higher thrombo-embolic risk (CHA2DS2VASc ≥2: 63.4% vs 40.2%; p < 0.001), had a higher body mass index (27.7 ± 3.9 vs 26.4 ± 3.9 kg/m2; p < 0.001), had a larger atrial diameter (43.8 ± 7.0 vs 40.2 ± 5.8 mm; p < 0.001), and had a lower LV ejection fraction (57.2 ± 7.7% vs 60.7 ± 6.0%; p < 0.001). At the time of ablation, 73% of patients were on class Ic or III anti-arrhythmic drugs. Procedure time (106.9 ± 41.5 vs 112.1 ± 46.8 min; p = 0.248), fluoroscopic time (28.7 ± 14.7 vs 28.6 ± 15.2 min; p = 0.819), and complication rate (3.9% vs 4.8%; p = 0.525) were not different between the SHD and non-SHD cohorts. However, the acute success rate (98.9% vs 97.7%; p = 0.016) was higher in patients with SHD. After a follow-up of 13.4 ± 12.8 months, freedom from symptomatic recurrence was 78.0% for SHD and 78.4% for non-SHD (p = 0.895). Recurrence rate was not related to either left atrial size or LVEF. In the SHD cohort, Class Ic or III anti-arrhythmic drugs treatment decreased from 70.7% of patients before ablation to 28.7% of patients after CB-PVI (p = 0.001). CONCLUSIONS: CB-PVI was extensively applied to treat patients with PAF. Unlike previous PVI experiences, the acute success and recurrence rate after a single procedure was not related to the presence of SHD or to the degree of cardiac remodelling. Further studies are required to define whether CB-PVI has a useful role in patients with a significantly reduced ejection fraction as those patients were under-represented in the current population.

Efficacy of cryoballoon ablation in patients with paroxysmal atrial fibrillation without time to pulmonary vein isolation assessment.

BACKGROUND: Real-time visualization of the electrical activity of the pulmonary veins (PV) is not always possible in the setting of atrial fibrillation (AF) cryoballoon ablation. We investigated the relation between the effective documentation of time to PV isolation and the clinical outcome in a cohort of patients with paroxysmal AF who underwent cryoballoon ablation. METHODS: One thousand forty two consecutive patients were enrolled. An inner lumen mapping catheter was typically used to visualize real-time electrical activity inside the PVs. RESULTS: Time to PV isolation was documented in all targeted PVs in 391 patients (Group 1), in 651 patients it was not possible to record PV potentials and assess time to PV isolation in at least one PV (Group 2). In Group 1 a longer procedure duration and ablation time were observed, while a longer fluoroscopy time was observed in Group 2. After a mean follow-up of 14 ±â€¯11 months, 209/1042 (20%) patients had an atrial arrhythmia recurrence (20.2% in Group 1, 19.9% in Group 2, p = 0.25). Complications occurred in 54/1042 (5.2%) patients without any difference among the two study groups. CONCLUSION: In our retrospective analysis, in about two thirds of patients undergoing cryoballoon ablation it was not possible to acutely assess time to PV isolation in all PVs. However, one-year freedom from clinically symptomatic atrial tachyarrhythmia was similar to that of patients in which time to PV isolation was documented in all targeted veins. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov (NCT01007474).

Contiguity Between Ablation Lesions and Strict Catheter Stability Settings Assessed by VISITAGTM Module Improve Clinical Outcomes of Paroxysmal Atrial Fibrillation Ablation　- Results From the VISITALY Study.

BACKGROUND: Our aim was to evaluate the clinical outcome of paroxysmal atrial fibrillation (AF) ablation with contact force technology, using an automated lesion tagging system (VISITAGTM module) with strict criteria of catheter stability.Methods and Results:We enrolled 200 consecutive patients who underwent pulmonary vein isolation (PVI) in 11 centers and were followed up for 12 months. The stability setting was within 3 mm for ≥10 s and for ≥15 s in 47% and 53% of patients, respectively. A mean of 67.2±21.9 VISITAGs was acquired. Freedom from atrial tachyarrhythmias at follow-up was 77.5% (155/200), and the contiguity between lesions was associated with a higher chronic success rate (96% vs. 77.1%; log-rank P=0.036). Radiofrequency (RF), fluoroscopy times, and recurrence rates at the 12-month follow-up were significantly lower than in a comparison group of 80 patients without VISITAGTM module (42.7±14.5 vs. 50.9±23.6 min; P=0.032; 11.6±7.8 vs. 18.4±12.8 min; P=0.003 and 22.5% vs. 41.2%; P=0.02). Two major complications (1 cardiac tamponade and 1 minor stroke) were observed only in the control group. CONCLUSIONS: Paroxysmal AF ablation with contact force technology and strict criteria of stability using the VISITAG module was a safe procedure, associated with an improvement in efficiency and a reduction of atrial tachyarrhythmia recurrence at the 12-month follow-up compared with manual annotation. Contiguity between lesions seemed to enhance effectiveness outcomes.

Multipoint pacing via a quadripolar left-ventricular lead: preliminary results from the Italian registry on multipoint left-ventricular pacing in cardiac resynchronization therapy (IRON-MPP).

AIMS: This registry was created to describe the experience of 76 Italian centres with a large cohort of recipients of multipoint pacing (MPP) capable cardiac resynchronization therapy (CRT) devices. METHODS AND RESULTS: A total of 507 patients in whom these devices had been successfully implanted were enrolled between August 2013 and May 2015. We analysed: (i) current clinical practices for the management of such patients, and (ii) the impact of MPP on heart failure clinical composite response and on the absolute change in ejection fraction (EF) at 6 months. Multipoint pacing was programmed to 'ON' in 46% of patients before discharge. Methods of optimizing MPP programming were most commonly based on either the greatest narrowing of the QRS complex (38%) or the electrical delays between the electrodes (34%). Clinical and echocardiographic follow-up data were evaluated in 232 patients. These patients were divided into two groups according to whether MPP was programmed to 'ON' (n = 94) or 'OFF' (n = 138) at the time of discharge. At 6 months, EF was significantly higher in the MPP group than in the biventricular-pacing group (39.1 ± 9.6 vs. 34.7 ± 7.6%; P < 0.001). Even after adjustments, early MPP activation remained an independent predictor of absolute increase in LVEF of ≥5% (odds ratio 2.5; P = 0.001). At 6 months, an improvement in clinical composite score was recorded in a greater proportion of patients with MPP-ON than in controls (56 vs. 38%; P = 0.009). On comparing optimal MPP and conventional vectors, QRS was also seen to have decreased significantly (P < 0.001). CONCLUSION: This study provides information that is essential in order to deal with the expected increase in the number of patients receiving MPP devices in the coming years. The results revealed different practices among centres, and establishing the optimal programming that can maximize the benefit of MPP remains a challenging issue. Compared with conventional CRT, MPP improved clinical status and resulted in an additional increase in EF. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrial.gov/. Unique identifier: NCT02606071.