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Background: Local impedance (LI) drop predicts acute conduction block during pulmonary vein isolation (PVI). Whether the LI drop predicts also the achievement of left atrial posterior wall isolation (LAPWI) in persistent atrial fibrillation (PersAF) patients is unknown. We evaluated the efficacy and the safety of LI drop-guided LAPW ablation by using high power (50 watts) and investigated the impact of ablation parameters on the LI drop., Methods: We included consecutive PersAF patients underwent PVI and both roof line and floor line completion to achieve LAPWI with a novel contact force (CF)- and LI-featured catheter (IntellaNAV Stablepoint™). For each radiofrequency (RF) application, we targeted a LI drop of 25 ohms., Results: Out of 30 patients, first-pass floor line block was achieved in 26 (87%) and first-pass roof line block in 17 (57%), resulting in first-pass LAPWI in 14 patients (47%). After touch-up ablations, LAPWI was achieved in 28 patients (93%) with endocardial ablation only. No procedural nor 1-month complications occurred. Overall, 877 RF applications were delivered: 787 ablation tags (89%) were associated with acute conduction block, while 90 (11%) were located at sites of acute gaps in either the roof or floor line. LI drop values were greater at segments with acute block than those with gaps (p < 0.001). At multivariable analysis, only LI drop and RF time remained independently associated with the acute block (p < 0.001; p = 0.001)., Conclusions: LI drop-guided LAPWI at a fixed power of 50 W was effective and did not lead to complications. LI drop was the most important predictor of acute conduction block., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: A very high-power short-duration (vHPSD) strategy of radiofrequency (RF) ablation aims to minimize conductive heating and increase resistive heating. We evaluated the feasibility, efficacy and safety of the vHPSD ablation of the cavotricuspid isthmus (CTI) in patients presenting with typical atrial flutter (AFL)., Methods: This prospective non-randomized study enrolled 28 consecutive patients (FAST Group) with typical AFL undergoing CTI ablation. The vHPSD ablation was performed applying 90 W, for 4 s, with an irrigation of 8 ml/min. Thirty consecutive patients who, previously, underwent CTI ablation by means of a contact force surrounding flow catheter guided by ablation index (500) served as control group (AI Group)., Results: In the FAST Group, the mean CTI length was 29 ± 6 mm, and the mean number of RF tags was 20 ± 9. The CTI bidirectional "first pass" block was reached in 25 (89%) patients. There were no major procedural complications. After a mean follow-up of 6 ± 2 months, one (3.5%) patient had arrhythmia recurrence. The vHPSD ablation was as effective as AI-guided ablation in achieving acute CTI block (rate of first pass 89% vs 93%, p = 0.59), with a shorter RF time (88 ± 40 s vs 492 ± 269 s, p < 0.001) and similar procedure (30 ± 4 min vs 34 ± 10 min, p = 0.5) and fluoroscopy time (103 ± 29 vs 108 ± 52 s, p = 0.7). At 8 months, the freedom from AFL recurrence was 96% in the FAST group and 97% in the AI group., Conclusions: Our preliminary data show that the vHPSD ablation represents an effective and safe ablation strategy to achieve bidirectional block for the treatment of typical AFL., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Multiple sclerosis does not seem to adversely affect fetal and neonatal outcomes, although some studies reported a possible reduction in mean birth weight and length, and a higher incidence of preterm delivery, mainly in relation to the exposure to disease-modifying drugs (DMDs) during pregnancy. Few data are available on intrauterine fetal growth and postnatal somatic development of newborns from mothers with multiple sclerosis compared to those from healthy women. For these reasons, we decided to investigate fetal growth, neonatal anthropometric parameters, and postnatal somatic development up to 12 months of life in offsprings from MS mothers., Methods: This retrospective cohort study included 211 women with multiple sclerosis, and 384 healthy women paired for maternal age and parity as controls. Fetal biometric parameters (biparietal diameter, head circumference, abdominal circumference, and femur length) measured during the third trimester of pregnancy (30-34 weeks' gestation) were retrieved from the computerized database of the Department (EcoPlus*) where the results of ultrasound exams performed in the hospital are stored. Newborn measurements (weight, length and head circumference) at birth were obtained from the hospital's computerized obstetric and neonatal database (Trackare* and Remote* data base); measurements at 6 and 12 months of life were obtained from the regional database (ECWMED*) of family pediatricians of our region., Results: No differences between the two groups were observed for all the fetal parameters considered, expressed as centiles of growth according to gestational age (biparietal diameter: p = 0.40; head circumference: p = 0.40; abdominal circumference: p = 0.32; femur length: p = 0.32). No differences in gestational age at delivery, birthweight, and in the incidence of low birthweight and small for gestational age newborns were observed between the two groups. In the multiple sclerosis group a significantly higher incidence of caesarean section (p = 0.01) and late preterm delivery (at less than 37 weeks'gestation, p = 0.001) were registered. The trends of postnatal growth in weight (F = 0.53; p-value = 0.590) and length (F = 0.44; p-value = 0.645) were superimposable between the two groups. The trends of growth for head circumference showed a slightly, not significantly greater head circumference of infants from mothers with multiple sclerosis at 6 months of life, but the values at twelve months of life in the two groups were similar (F = 0.85; p-value = 0.427) . Moreover, the trends of postnatal increase of weight (F = 1.016; p-value = 0.331), length (F = 2.001; p-value = 0.146) and head circumference (F = 1.591; p-value = 0.212) of newborns/infants (from birth to twelve months of life) born to mothers with multiple sclerosis who breastfed, mothers who did not, and in the control group were similar., Conclusion: Multiple sclerosis in pregnancy does not seem to affect fetal growth and postnatal development during the first year of the offspring life. We think that these results represent an important and reassuring information to provide the patients with during preconception counseling., (Copyright © 2022. Published by Elsevier B.V.)

Background: The relationship between dietary habits and multiple sclerosis (MS) risk is still controversial. Most studies have involved populations from Scandinavia, North America, and Australia. Data on populations from southern Europe (an area of high MS prevalence) are scarce., Objective: To examine the association between dietary habits/nutritional status and risk of a first demyelinating event, in a southern European incident cohort., Methods: In this incident case-control study, a detailed nutritional assessment was performed by a registered dietitian in patients with a first demyelinating event, and in age-/sex-matched controls. Body composition analysis, anthropometric evaluation, and blood tests for nutritional status were also performed., Results: Eighty-three patients with a first demyelinating event were prospectively recruited over a 1-year period. Low intake of fibers (OR 0.846, p = 0.014), vitamin D (OR 0.730, p < 0.0001), and alpha-linolenic acid (OR 0.283, p = 0.014), high BMI (OR 1.132, p = 0.028), and ever smoker status (OR 4.472, p = 0.003) were all independently associated with risk of a first demyelinating event. Higher intake of rapid absorption carbohydrates, lower intake of vegetal proteins, and higher intake of animal proteins were observed in patients with a first demyelinating event., Conclusions: Significant differences between patients and controls are observed in the dietary habits at the time of a first demyelinating event, suggesting low intake of fibers, vitamin D and alpha-linolenic acid as the main dietary risk factors. Furthermore, high cardiovascular risk dietary habits are frequent at the time of MS onset, suggesting the usefulness of nutritional intervention as part of the activities of MS centers., (© 2022. Fondazione Società Italiana di Neurologia.)

Introduction: Low-voltage activity beyond pulmonary veins (PVs) may contribute to the failure of ablation of atrial fibrillation (AF) in the long term. We aimed to assess the presence of gaps (PVG) and residual potential (residual antral potential [RAP]) within the antral scar by means of an ultra-high-density mapping (UHDM) system., Methods: We studied consecutive patients from the CHARISMA registry who were undergoing AF ablation and had complete characterization of residual PV antral activity. The Lumipoint™ (Boston Scientific) map-analysis tool was used sequentially on each PV component. The ablation endpoint was PV isolation (PVI) and electrical quiescence in the antral region., Results: Fifty-eight cases of AF ablation were analyzed. A total of 86 PVGs in 34 (58.6%) patients and 44 RAPs in 34 patients (58.6%) were found. In 16 (27.6%) cases, we found at least one RAP in patients with complete absence of PV conduction. RAPs showed a lower mean voltage than PVG (0.3 ± 0.2 mV vs. 0.7 ± 0.5 mV, p < .0001), whereas the mean number of electrogram peaks was higher (8.4 ± 1.4 vs. 3.2 ± 1.5, p < .0001). The percentage of patients in whom RAPs were detected through Lumipoint™ was higher than through propagation map analysis (58.6% vs. 36.2%, p = .025). Acute procedural success was 100%, with all PVs successfully isolated and RAPs completely abolished in all study patients. During a mean follow-up of 453 ± 133 days, 6 patients (10.3%) suffered an AF/AT recurrence., Conclusion: Local vulnerabilities in antral lesion sets were easily discernible by means of the UHDM system in both de novo and redo patients when no PV conduction was present., (© 2022 Wiley Periodicals LLC.)

Introduction: A new dielectric-based method (KODEX-EPD mapping system, EPD Solutions, a Philips company) for measuring tissue thickness at the catheter-tissue interface has recently been developed. We reported preliminarydata on real-time catheter-based measuring myocardial wall thickness in vivo, during typical atrial flutter radio frequency ablation., Methods and Results: The study population consisted of 12 consecutive patients, suffering from symptomatic paroxysmal or persistent cavo-tricuspid isthmus dependent, counter clockwise and clockwise AFL, under going a first catheter ablation between April 2021 and November 2021. The new KODEX-EPD function, Wall Viever, was used to calculate atrialwall thickness. The atrial wall thickness was significantly higher closeto the tricuspid annulus than close to the inferior vena cava (3.6 ± 0.5 mm vs 2.4 ± 0.3 mm, p < .001) and a trend towards a progressive decrease of atrial wall thickness was observed moving the mapping catheter from the tricuspidvalve to the inferior vena cava., Conclusions: Thenew KODEX-EPD function, Wall Viever, allowed us to assess atrial wall thickness during atrial flutter radio frequency ablation., (© 2022 Wiley Periodicals LLC.)

Background: The antral region of pulmonary veins (PV)s seems to play a key role in a strategy aimed at preventing atrial fibrillation (AF) recurrence. Particularly, low-voltage activity in tissue such as the PV antra and residual potential within the antral scar likely represent vulnerabilities in antral lesion sets, and ablation of these targets seems to improve freedom from AF. The aim of this study is to validate a structured application of an approach that includes the complete abolition of any antral potential achieving electrical quiescence in antral regions., Methods: The improveD procEdural workfLow for cathETEr ablation of paroxysmal AF with high density mapping system and advanced technology (DELETE AF) study is a prospective, single-arm, international post-market cohort study designed to demonstrate a low rate of clinical atrial arrhythmias recurrence with an improved procedural workflow for catheter ablation of paroxysmal AF, using the most advanced point-by-point RF ablation technology in a multicenter setting. About 300 consecutive patients with standard indications for AF ablation will be enrolled in this study. Post-ablation, all patients will be monitored with ambulatory event monitoring, starting within 30 days post-ablation to proactively detect and manage any recurrences within the 90-day blanking period, as well as Holter monitoring at 3, 6, 9, and 12 months post-ablation. Healthcare resource utilization, clinical data, complications, patients' medical complaints related to the ablation procedure and patient's reported outcome measures will be prospectively traced and evaluated., Discussion: The DELETE AF trial will provide additional knowledge on long-term outcome following a structured ablation workflow, with high density mapping, advanced algorithms and local impedance technology, in an international multicentric fashion. DELETE AF is registered at ClinicalTrials.gov (NCT05005143)., (© 2022 The Authors. Clinical Cardiology published by Wiley Periodicals LLC.)

Introduction: The COVID-19 pandemic caused major changes in the lifestyle and in the access to health services worldwide. Progressive multiple sclerosis (pMS) patients are a vulnerable population at high risk of disability worsening., Objective and Methods: The objective of this study was to assess the health outcomes of COVID-19 lockdown in a cohort of 225 pMS patients., Results: Worsening of neurological disability (19.7%) and fatigue (32.4%), depression (30.4%), and weight increase (28.3%) were observed in pMS patients during lockdown, along with discontinuation of regular physical exercise (47.1%) and of physical therapy (59.3%)., Conclusion: These results highlight the adverse impact, on pMS patients, of the public health measures implemented for the containment of the pandemic., (© 2022. Fondazione Società Italiana di Neurologia.)

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., (© 2022. The Author(s).)

Pulmonary vein (PV) isolation using cryoballoon (CB) catheter is generally characterized by a high radiation and contrast media exposure. A new dielectric imaging system (KODEX-EPD imaging system) allows pulmonary vein (PV) occlusion assessment without dye use. The purpose of this study was to verify the feasibility of reducing the radiation and dye use during CB ablation in patients with atrial fibrillation (AF) using the new dielectric imaging system. In a retrospective, single center study, we enrolled 34 consecutive patients with paroxysmal AF divided in two groups: 17 patients in Conventional Group underwent the procedure under fluoroscopy guidance before the new system introduction, while 17 patient in KODEX-EPD Group underwent the procedure under fluoroscopy and KODEX-EPD imaging system guidance. There were no differences in any clinical and anatomical characteristics between the two study groups. Overall procedure time was comparable between the two groups (69 [IQR 63-98] min in Conventional Group vs. 65 [IQR 58-74] min in KODEX-EPD Group, p = 0.16), while fluoroscopy time (8 [IQR 5-9] min vs. 11 [IQR 9-12] min, p = 0.014) and dye use (35 [IQR 28-45] ml vs. 70 [IQR 57-83] ml, p < 0.001) were significantly lower in the KODEX-EPD Group. No 30-day complications were observed. At 12-month follow-up 7/37 (19%) patients had an atrial arrhythmias recurrence, without any difference between the two study groups (17.6% vs. 23.5%, p = 0.68). The use of a new dielectric imaging system allowed a significantly reduction in radiation exposure and dye use during CB ablation in patients with AF., (© 2021. Springer Japan KK, part of Springer Nature.)

Introduction: A very high-power short-duration (vHPSD) strategy of radiofrequency (RF) ablation aims to minimize conductive heating and increase resistive heating. This study aimed to clarify the contribution of contact force (CF) and temperature and their interrelationship in making an adequate lesion with the vHPSD catheter., Methods: We enrolled 46 consecutive patients undergoing first catheter ablation for atrial fibrillation (AF). The vHPSD ablation was performed applying 90 W, for 4 s, with an irrigation of 8 ml/min. During an application, an impedance drop (ID) ≥10 Ω was regarded as an adequate lesion formation., Results: The mean procedural time was 95 ± 15 min. First-pass isolation was reached in 89% of patients and at the end of the procedure all pulmonary veins were isolated. No steam pop nor procedural complication occurred. A total of 3829 qualified RF points were analyzed and the median values of ID, CF and maximum temperature were respectively 10.6 (IQR 8.6-13.1) Ohm, 9 (5.8-13.8) g, 46.8 (44.1-49.8) °C. The mean ID significantly increased in parallel with the increasing CF as well as with the increasing maximum temperature. In the multivariable analysis only the CF and the maximum temperature were independent predictors of ID. From receiver operating characteristic curve analysis, a CF of 8 g and a maximum temperature of 47°C are the optimal cutoff discriminatory value for adequate lesion formation., Conclusions: The vHPSD ablation is highly effective and safe. The CF and the maximum temperature are independent predictors of adequate lesion formation assessed by means of ID., (© 2021 Wiley Periodicals LLC.)

Background: Current guidelines recommend avoiding apical left ventricular (LV) pacing for cardiac resynchronization therapy (CRT)., Aims: We investigated the feasibility of nonapical pacing with the current quadripolar LV lead technology., Methods: We analyzed consecutive patients who received CRT with an LV quadripolar lead. The post--implantation position of each electrode of the LV lead was designated as basal, mid, or apical. The pacing capture threshold (PCT) and phrenic nerve stimulation (PNS) threshold were assessed for each electrode., Results: We enrolled 168 patients. A total of 8 CRT defibrillators were from Biotronik (with Sentus OTW QP leads), 98 were from Boston Scientific (with 21 Acuity X4 Spiral and 77 Acuity X4 Straight leads), and 62 from St. Jude Medical (with Quartet leads). The median (interquartile range) number of electrodes at nonapical segments per patient was 3 (1-4) with Biotronik Sentus leads, 4 (3-4) with spiral -design Boston Scientific leads, 4 (3-4) with straight Boston Scientific leads, and 3 (3-4) with St. Jude Medical Quartet leads (P = 0.045). Three patients (38%) with Biotronik Sentus leads, 21 (100%) with spiral -design Boston Scientific leads, 69 (90%) with straight -design Boston Scientific leads, and 49 (79%) with St. Jude Medical Quartet leads (P <0.001) had at least 1 electrode located at nonapical segments linked with a PNS -PCT safety margin of more than 2 V. During the 6-month follow -up, PNS was detected in 4 patients and was eliminated with reprogramming. No significant changes in PCT were detected during follow -up., Conclusions: Quadripolar leads allowed nonapical pacing with acceptable electrical parameters in the majority of CRT recipients, although differences were found among the currently available devices.

The association of situs inversus totalis and left ventricular noncompaction is very rare and poses several and unique challenges if endo-epicardial ablation has to be performed, both for anatomical access to the target area and for arrhythmia complexity. We report a case of incessant ventricular tachycardia with endo-epicardial involvement that required ablation in both surfaces to obtain final noninducibility., Competing Interests: Dr Francesco Solimene and Giuseppe Stabile have received speaker's fees from Boston Scientific Corporation. Francesco Maddaluno is a Boston Scientific employee., (© 2021 The Authors. Journal of Arrhythmia published by John Wiley & Sons Australia, Ltd on behalf of the Japanese Heart Rhythm Society.)

Aims: Ablation index (AI) is a marker of lesion quality during catheter ablation that incorporates contact force, time, and power in a weighted formula. This index was originally developed for pulmonary vein isolation as well as other left atrial procedures. The aim of our study is to evaluate the feasibility and efficacy of the AI for the ablation of the cavotricuspid isthmus (CTI) in patients presenting with typical atrial flutter (AFL)., Methods and Results: This prospective multicentre non-randomized study enrolled 412 consecutive patients with typical AFL undergoing AI-guided cavotricuspid isthmus ablation. The procedure was performed targeting an AI of 500 and an inter-lesion distance measurement of ≤6 mm. The primary endpoints were CTI 'first-pass' block and persistent block after a 20-min waiting time. Secondary endpoints included procedural and radiofrequency duration and fluoroscopic time. A total of 412 consecutive patients were enrolled in 31 centres (mean age 64.9 ± 9.8; 72.1% males and 27.7% with structural heart disease). The CTI bidirectional 'first-pass' block was reached in 355 patients (88.3%), whereas CTI block at the end of the waiting time was achieved in 405 patients (98.3%). Mean procedural, radiofrequency, and fluoroscopic time were 56.5 ± 28.1, 7.8 ± 4.8, and 1.9 ± 4.8 min, respectively. There were no major procedural complications. There was no significant inter-operator variability in the ability to achieve any of the primary endpoints., Conclusion: AI-guided ablation with an inter-lesion distance ≤6 mm represents an effective, safe, and highly reproducible strategy to achieve bidirectional block in the treatment of typical AFL., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2020. For permissions, please email: journals.permissions@oup.com.)

Background: Optimal pulmonary vein (PV) occlusion, usually verified with selective contrast injection, is mandatory to obtain an effective PV isolation during cryoballoon (CB) ablation., Aim of the Study: The purpose of this study was to verify the feasibility and the accuracy of a new dielectric sensing system in assessing PV occlusion during CB ablation in patients with atrial fibrillation (AF)., Methods: We enrolled 28 consecutive patients with paroxysmal or persistent AF. After transseptal access, a detailed image reconstruction of left atrium and PVs was achieved with an octapolar or decapolar mapping catheter (Achieve catheter, Medtronic Inc.) and KODEX-EPD system (EPD Solutions, a Philips company). The degree of PV occlusion with the inflated Arctic Front Advance Cryoballoon (Medtronic Inc.) was verified using the new "occlusion tool" software module (EPD Solutions, a Philips company) and compared to an angiogram obtained with contrast medium injection in each PV., Results: A total of 105 PV CB occlusion were tested. The new occlusion tool software module showed a 91% sensitivity and 76% specificity in assessing a complete PV occlusion verified with contrast medium injection. The positive predictive value was 80%, and the negative predictive value was 88.6%. Mean procedure time was 81 ± 17 minutes. Mean fluoroscopy time was 6 ± 2 minutes. No 30-day complications were observed., Conclusion: The new dielectric imaging system was able to assess the degree of PV occlusion during a CB ablation with good sensitivity and specificity., (© 2020 Wiley Periodicals LLC.)

Introduction: Recently, a novel technology able to measure local impedance (LI) and tissue characteristics has been made available for clinical use. This analysis explores the relationships among LI and generator impedance (GI) parameters in atrial fibrillation (AF) patients. Characterization of LI among different ablation spots and procedural success were also evaluated., Methods and Results: Consecutive patients undergoing AF ablation from the CHARISMA registry at five Italian centers were included. A novel radiofrequency (RF) ablation catheter with a dedicated algorithm (DIRECTSENSE™) was used to measure LI and to guide ablation. The ablation endpoint was pulmonary vein (PV) isolation. We analyzed 2219 ablation spots created around PVs in 46 patients for AF ablation. The mean baseline tissue impedance was 105.8 ± 14 Ω for LI versus 91.8 ± 10 Ω for GI (p < .0001). Baseline impedance was homogenous across the PV sites and proved higher in high-voltage areas than in intermediate- and low-voltage areas and the blood pool (p < .001). Both LI and GI displayed a significant drop after RF delivery, and absolute LI drop values were significantly larger than GI drop values (14 ± 8 vs. 3.7 ± 5 Ω, p < .0001). Every 5-point increment in LI drop was associated with successful ablation (odds ratio = 3.05, 95% confidence interval: 2.3-4.1, p < .0001). Conversely, GI drops were not significantly different comparing successful versus unsuccessful sites (3.7 ± 5 vs. 2.8 ± 4 Ω, p = .1099). No steam pops or major complications occurred during or after the procedures. By the end of the procedures, all PVs had been successfully isolated in all patients., Conclusions: The magnitude of the LI drop was more closely associated with effective lesion formation than the GI drop., (© 2020 Wiley Periodicals LLC.)

Purpose: Reconnection of pulmonary veins (PVs) remains common following radiofrequency catheter ablation for atrial fibrillation (AF). Ablation Index (AI) is a novel ablation quality marker that incorporates stability, contact force (CF), time, and power in a weighted formula. Its use seems to improve lesion durability. This is a prospective, single-arm registry to investigate on the safety and mid-term efficacy of AF ablation guided by the AI., Methods: One hundred fifty-six consecutive patients (mean age 58 ± 10 years, 49% males, 44% with structural heart disease) referred for paroxysmal (124) or persistent (32) AF underwent antral PV isolation using a surround flow CF-sensing catheter guided by the AI. Radiofrequency was delivered targeting interlesion distance ≤ 6 mm and Ablation Index of 330-350 at posterior wall and 400-450 at anterior wall., Results: Mean overall procedure time was 95 ± 30 min with a mean fluoroscopy time of 5 ± 6 min. Mean ablation time was 26 ± 10 min, 627/628 targeted PV were isolated. One pericardial effusion and two groin hematomas were reported; none required intervention. During a mean follow-up of 14 ± 6 months, 17 (10.8%) (9% paroxysmal AF vs 22% persistent AF, p = 0.09) patients had an atrial arrhythmia recurrence., Conclusions: PV ablation guided by AI resulted feasible, achieving a high rate of isolated PVs, with a low complication rate, and allowed a high single-procedure arrhythmia-free survival at 14 months.

Background: Cavotricuspid isthmus (CTI) radiofrequency (RF) catheter ablation is the standard treatment for patients suffering from CTI-dependent atrial flutter (AFL). The aim of this study was to compare the use in clinical practice of 8-mm gold-tip catheter (8mmRFC) and open-irrigated gold-tip catheter (irrRFC) for RF typical AFL ablation., Methods: Patients with typical AFL were treated with 8mmRFC or irrRFC catheters according to investigator preferences. The primary endpoint was the cumulative radiofrequency time (CRFT). Fluoroscopy time, acute and 6-month success rates were secondary endpoints., Results: After excluding 3 patients with left AFL, 157 of the enrolled patients (median age 71.8 [interquartile range, 64.1-76.2], 76% men, 91% in NYHA class ≤II, 65% with no structural heart disease) were analyzed: 74 (47%) subjects were treated with the 8mmRFC and 83 (53%) with the irrRFC. The median CRFT was 3 [2-6] minutes in the 8mmRFC group and 5 [3-7] minutes in the irrRFC group ( P  = .183). There were no significant differences in ablation success rates, intraprocedural CTI reconnections, audible steam pops, and procedural times. In the 8mmRFC group, a significantly lower fluoroscopy time was observed as compared to the irrRFC group (8 [5-12] vs 15 [10-20] minutes, P  < .001). During the follow-up period, AFL recurrences were documented in 3 patients in the 8mmRFC group and 2 in the irrRFC group ( P  = .655)., Conclusions: The 8mmRFC and the irrRFC performed similarly in routine practice for CTI ablation in terms of cumulative RF time, acute and 6-month success rates. Fluoroscopy time was significantly lower in the 8mmRFC group.

Proper localization of the anatomical target during ablation of the accessory pathways (AP) and the ability to detect clear AP potentials on the ablation catheter are crucial for successful AP ablation. We report a case of recurring AP conduction that was finally eliminated using a novel ablation catheter equipped with high-resolution mini-electrodes. Smaller and closer electrodes result in high mapping resolution with less signal averaging and cancellation effects. Owing to improved sensitivity, the new catheter seems effective in detecting fragmented and high frequency signals, thus allowing more effective radiofrequency application and improving ablation success.

Introduction: Pulmonary vein (PV) isolation is the cornerstone of catheter ablation in patients with atrial fibrillation (AF). Surround flow and contact force (CF) measurement capabilities might enhance procedure efficacy and safety. We report on the safety and midterm efficacy of a novel ablation catheter for PV isolation in patients with AF., Methods and Results: Two hundred thirty-three consecutive patients (57 ± 11 years, 76% males, 51% with structural heart disease), referred for paroxysmal (157) or persistent (76) AF, underwent PV isolation by a surround flow catheter with CF measurement capability in four centers. Ablation was guided by electroanatomic mapping allowing radiofrequency (RF) energy delivery in the antral region aiming at PV isolation. Mean overall procedure time was 100 ± 42 minutes with a mean fluoroscopy time of 6 ± 5 minutes. Mean ablation time was 31±15 minutes; 99% of the targeted veins were isolated. The mean CF value during ablation was 13 ± 4 g. Intraprocedural early (30 minutes) PV reconnection occurred in 12% PVs, and all PVs were effectively reisolated. One pericardial effusion and five groin hematomas were reported. During a mean follow-up of 12 ± 6 months, 30 (12.9%) (10% paroxysmal AF vs. 18% persistent AF, P = 0.07) patients had an atrial arrhythmias recurrence., Conclusions: In this multicenter registry, RF ablation using a new surround flow catheter, with CF sensor, resulted as feasible, achieving a high rate of isolated PVs. Procedural and fluoroscopy times and success rates were comparable with other techniques with a low complication rate., (© 2017 Wiley Periodicals, Inc.)

Background: Pulmonary vein (PV) isolation is the cornerstone of catheter ablation in patients with atrial fibrillation (AF). "Single-shot" ablation devices have been recently engineered., Objectives: We report on the safety and efficacy of a novel ablation catheter for PV isolation in patients with AF., Methods: One hundred eighty consecutive patients (58 ± 10 years, 125 male, 31% with structural heart disease) referred for paroxysmal (140) or persistent (40) AF underwent PV isolation by an open-irrigated mapping and radiofrequency (RF) decapolar ablation catheter in 7 centers. Ablation was guided by electroanatomic mapping, allowing RF energy delivery in the antral region of PVs from 10 irrigated electrodes simultaneously., Results: Mean overall procedure time was 113 ± 53 minutes with a mean fluoroscopy time of 13.1 ± 8.4 minutes. The use of a preablation PV imaging related to a significant reduction in fluoroscopy time (from 14.7 ± 9.7 to 8.7 ± 6.6, P < .001). Mean ablation time was 12.5 ± 5.1 minutes, and 98% of the targeted veins were isolated with a mean of 23.4 ± 6.3 RF pulses per patient. In only 4 patients (2.2%) a single-point ablation strategy was required to achieve PV isolation. One groin hematoma and 1 PV stenosis were reported. During a mean follow-up of 13.9 ± 8.2 months 38 of 140 patients (27%) with paroxysmal AF and 12 of 40 patients (30%) with persistent AF had an atrial arrhythmia relapse (P = .671)., Conclusions: In this multicenter registry, irrigated multielectrode RF ablation proved feasible, achieving a high rate of isolated PVs. Procedural and fluoroscopy times and success rates were comparable with other techniques, with a low complication rate., (Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

The creation of a durable radiofrequency (RF) lesion depends on several parameters, including catheter tip electrode size and composition, tip orientation, temperature, RF pulse duration, power, blood flow, and catheter to tissue contact. The development of new contact force (CF) sensor catheters has allowed the measurement of the tip to tissue CF during the RF ablation procedure. Here, we describe the clinical experience obtained using CF catheters for atrial fibrillation ablation, with a specific focus on the impact of CF technology on acute procedural data (procedure and fluoroscopy time).

Purpose: Catheter-tissue contact is critical for effective lesion creation in radiofrequency catheter ablation (RFCA). In a multicenter prospective study, we assessed the relationship between catheter contact force (CF) during RFCA for paroxysmal atrial fibrillation (AF) and clinical recurrences over a mid-term follow-up., Methods: All patients underwent RFCA for paroxysmal AF by antral pulmonary vein (PV) isolation, aiming at entry and exit conduction block in all PVs. A new open-irrigated tip catheter with CF sensing (SmartTouch(TM), Biosense Webster Inc. CA) was used. All patients were followed for at least 12 months and the relationship between CF and clinical outcomes assessed., Results: One year follow-up was available in 92/95 of the patients enrolled. Acute PV isolation was achieved in 100 % of the veins. Mean CF during RFCA was 12.2 ± 3.9 g. Mean force-time integral (FTI) was 733 ± 505 gs. Following the 3-month blanking period, 17 (18 %) patients experienced at least 1 atrial tachyarrhythmia relapse. There was no statistical difference in mean CF (13 ± 3.4 g vs 12 ± 4 g, p = 0.32) and mean FTI (713 ± 487 gs vs 822 ± 590 gs, p = 0.42) between patients with and without arrhythmia recurrences. Recurrences were recorded in 22 % of patients achieving a mean FTI value below the median of 544 gs and in 15 % of patients with a mean FTI value above the median (p = 0.64)., Conclusions: RFCA with CF data during PV isolation for paroxysmal AF improves physician's knowledge on catheter-tissue contact. In the present dataset, however, higher CF values did not impact mid-term clinical RFCA outcome.

Aims: About 30 to 50% of patients undergoing cardiac resynchronization therapy (CRT) may not show clinical or echocardiographic improvement, despite fulfilling guidelines recommendations for CRT. For this reason, we need a more accurate method to assess CRT eligibility. The aims of this study were to verify, on a 12-month follow-up, the usefulness of QT corrected dispersion (QTcD) in a patient's selection for CRT., Methods: We stratified 53 patients who underwent CRT, into two groups based on the estimation of QTcD, that is, QTcD > 60 ms and QTcD ≤ 60 ms. In all patients were performed New York Heart Association (NYHA) class determination, six-minute walking test, QtcD, and QRS measurements, and complete echocardiographic assessment at 1, 3, 6, and 12 months after implantation., Results: At baseline, there were no significant differences in clinical, echocardiographic, and electrocardiographic parameters duration between two groups. At 12-month follow-up between the two groups, there were significant differences in NYHA (1.2 ± 0.4 vs 2 ± 0.6; P < 0.01), six-minute walking distance (422 ± 68 vs 364 ± 68; P < 0.01), left ventricular (LV) ejection fraction (34 ± 7% vs 28 ± 6%; P < 0.01), LV end-diastolic diameter (57 ± 7 vs 63 ± 8; P < 0.01), and LV intraventricular dyssynchrony (24 ± 14 vs 39 ± 23; P < 0.01)., Conclusion: This study suggests that QTc dispersion in addition to QRS duration could improve the sensitivity of electrocardiogram in a patient's selection for CRT., (©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.)

Aims: To compare functional and structural changes of the left ventricle and long-term clinical outcomes in diabetic and nondiabetic patients with heart failure undergoing cardiac resynchronization therapy (CRT)., Methods: Sixty-eight patients with heart failure undergoing CRT were included: 18 were diabetic patients and 50 nondiabetic patients. The CRT eligibility was established by echocardiographic assessments., Results: CRT improved ventricular geometry and dyssynchrony in both diabetic and nondiabetic patients, with no significant difference in the magnitude of the effects on the left ventricular function. Over a median follow-up of 30.6 ± 6.2 months, there were no significant differences in the rates of any cause death (16.7 vs. 14.0%, P = 0.72), cardiac death (11.1 vs. 8.0%, P = 0.65) and heart rehospitalization (5.6 vs. 6.0%, P = 1.0), between diabetic and nondiabetic patients, respectively. Diabetes was not found to be an independent factor associated with worse clinical outcome., Conclusion: Resynchronization therapy provided significant functional and hemodynamic improvements in both diabetic and nondiabetic patients. Long-term prognosis in heart failure patients with diabetes was comparable with that in those without diabetes.