The PhysioVP-AF study, a randomized controlled trial to assess the clinical benefit of physiological ventricular pacing vs. managed ventricular pacing for persistent atrial fibrillation prevention in patients with prolonged atrioventricular conduction: design and rationale.

AIMS: In patients with prolonged atrioventricular (AV) conduction and pacemaker (PM) indication due to sinus node disease (SND) or intermittent AV-block who do not need continuous ventricular pacing (VP), it may be difficult to determine which strategy to adopt. Currently, the standard of care is to minimize unnecessary VP by specific VP avoidance (VPA) algorithms. The superiority of this strategy over standard DDD or DDD rate-responsive (DDD/DDDR) in improving clinical outcomes is controversial, probably owing to the prolongation of the atrialventricular conduction (PR interval) caused by the algorithms. Conduction system pacing (CSP) may offer the most physiological-VP approach, providing appropriate AV conduction and preventing pacing-induced dyssynchrony. METHODS AND RESULTS: PhysioVP-AF is a prospective, controlled, randomized, single-blind trial designed to determine whether atrial-synchronized conduction system pacing (DDD-CSP) is superior to standard DDD-VPA pacing in terms of 3-year reduction of persistent-AF occurrence. Cardiovascular hospitalization, quality-of-life, and safety will be evaluated. Patients with indication for permanent DDD pacing for SND or intermittent AV-block and prolonged AV conduction (PR interval > 180 ms) will be randomized (1:1 ratio) to DDD-VPA (VPA-algorithms ON, septal/apex position) or to DDD-CSP (His bundle or left bundle branch area pacing, AV-delay setting to control PR interval, VPA-algorithms OFF). Approximately 400 patients will be randomized in 24 months in 13 Italian centres. CONCLUSION: The PhysioVP-AF study will provide an essential contribution to patient management with prolonged AV conduction and PM indication for sinus nodal disease or paroxysmal 2nd-degree AV-block by determining whether CSP combined with a controlled PR interval is superior to standard management that minimizes unnecessary VP in terms of reducing clinical outcomes.

Electroanatomic voltage mapping for tissue characterization beyond arrhythmia definition: A systematic review.

Three-dimensional (3D) reconstruction by means of electroanatomic mapping (EAM) systems, allows for the understanding of the mechanism of focal or re-entrant arrhythmic circuits, which can be identified by means of dynamic (activation and propagation) and static (voltage) color-coded maps. However, besides this conventional use, EAM may offer helpful anatomical and functional information for tissue characterisation in several clinical settings. Today, data regarding electromechanical myocardial viability, scar detection in ischaemic and nonischaemic cardiomyopathy and arrhythmogenic right ventricle dysplasia (ARVC/D) definition are mostly consolidated, while emerging results are becoming available in contexts such as Brugada syndrome and cardiac resynchronisation therapy (CRT) implant procedures. As part of an invasive procedure, EAM has not yet been widely adopted as a stand-alone tool in the diagnostic path. We aim to review the data in the current literature regarding the use of 3D EAM systems beyond the definition of arrhythmia.

Left ventricle pacing challenges in cardiac resynchronization therapy systems.

Left ventricle (LV) pacing can be considered peculiar due to its different lead/tissue interface (epicardial pacing) and the small vein wedging lead locations with less reliable lead stability. The current technologies available for LV capture automatic confirmation adopt the evoked response (ER), as well as "LV pace to right ventricular (RV) sense" algorithms. The occurrence of anodal RV capture is today completely solved by the use of bipolar LV leads, while intriguing data are recently published regarding the unintentional LV anodal capture beside the cathodal one, which may enlarge the front wave of cardiac resynchronization therapy (CRT) delivery. The LV threshold behavior over time leading to ineffective CRT issues (subthreshold stimulation or concealed loss of capture), the extracardiac capture with phrenic nerve stimulation (PNS), the flexible electronic cathode reprogramming and the inadequate CRT delivery related to inadequate AV and VV pace timing (and its management by LV "dromotropic pace-conditioning") are discussed. Moreover, recently, His bundle pacing (HBP) and left bundle branch pacing (LBBP) have shown growing interest to prevent pacing-induced cardiomyopathy as well as for direct intentional CRT. The purpose of the present review is to explore these new challenges regarding LV pacing starting from old concepts.

Left ventricle automatic pacing threshold management in CRT systems: A comprehensive review.

Modern cardiac resynchronization therapy (CRT) device-based threshold detection enables capture management and voltage output adjusting to combine consistent left ventricular (LV) pacing with acceptable battery drainage. The current technologies available for LV capture automatic confirmation in most cases require the evoked response, as well as "LV pace to right ventricular sense" algorithms. The LV pacing percentage counter may overestimate the CRT delivery which may be reduced due to pacing inhibition (by sensed LV activation) or inadequate capture due to subthreshold current or pacing into refractory tissue. Moreover, the LV threshold at implant and its behavior over time (as a marker of electrical viability) and the ineffective CRT issues (subthreshold stimulation or concealed loss of capture) are discussed. The purpose of the present review is to explore these new challenges regarding LV pacing automatic management.

Insights on arrhythmia termination and type 2 breaks after ICD therapy delivery.

Introduction of anti-tachycardia pacing (ATP) therapy and longer detection intervals delivery have allowed to safely reduce unnecessary shocks, improving survival and quality of life in implantable cardioverter defibrillator (ICD) patients. However, there are still outstanding issues, especially regarding the mode of arrhythmias termination after ATP or shock delivery. Regardless of ICD therapy efficacy, the arrhythmia interruption does not always occur abruptly, indeed both nonsustained tachy- or bradyarrhythmias have been described after ICD therapy delivery, being the former classified as type 2 interruption. Several physiopathological mechanisms have been suggested to be responsible for this phenomenon. Our aim is to review current data on postshock and post-ATP arrhythmias and to give insights on their possible mechanisms.

Ventricular tachycardia oversensing in S-ICD patients: Case-based brief review.

A 76-year-old woman with permanent atrial fibrillation and a mechanical aortic valve came to our attention. Echocardiography showed a 50-55% ejection fraction (EF) with good prosthesis performance. For symptomatic bradyarrhythmia, she received a VVI pacemaker (Proponent MRI L2010 model; Boston Scientific.). During follow-up, frequent symptomatic (presyncopal) episodes of nonsustained episodes of ventricular tachycardia (VT) were detected. Amiodarone proved unsuccessful; she was then offered an upgrade to an implantable cardioverter defibrillator (ICD) and a subcutaneous ICD (S-ICD) was chosen by the patient. A few weeks later, two sustained VT were detected and effectively treated with 80-J shock delivery. In both cases, device interrogation revealed a VT rate around 163 bpm (370 ms cycle length), below the lowest device detection cutoff. The report is a case-based review.

Single-center experience with wearable cardioverter-defibrillator as a bridge before definitive ICD implantation.

BACKGROUND: The wearable cardioverter-defibrillator (WCD) has been approved for patients with poor left ventricular ejection fraction (LVEF) who are at risk of sudden arrhythmic death for a limited period but are not candidates for a definitive implantable cardioverter-defibrillator (ICD). The present study sought to retrospectively analyse our single-centre experience. METHODS AND RESULTS: All consecutive WCDs applied between April 2017 and September 2018 in our centre were enrolled. An exercise test was performed in all patients in order to evaluate the absence of false detection of ventricular arrhythmias by the device. A total of 16 patients (57.7 ± 14.8 years old; 75% males) were taken into consideration for the analysis. Mean LVEF was 32 ± 11% at diagnosis and 42 ± 10% at last follow-up (mean, 3.1 ± 1.7 months; median, 3 months). At the end of the "wearing period" 11/16 patients (69%) did not have ICD implant indications and only 5 (31%) underwent ICD implantation. Neither appropriate nor appropriate shocks occurred during the follow up. CONCLUSIONS: The WCD represents a useful tool to bridge a temporarily increased risk for sudden cardiac death. The proportion of patients with an improvement of LVEF> 35% beyond the WCD-application period was considerable.

Safety steps for a non-fluoroscopic approach in right-sided electrophysiology procedures: A point of view.

BACKGROUND: Electro-anatomic 3D mapping systems enable the fluoroscopy (FL) exposure to be reduced. In right-heart supraventricular tachycardia (SVT) procedures, FL could potentially be avoided. Our aim was to discuss some steps focusing on safety. METHODS AND RESULTS: The patient cohort comprised 70 consecutive SVT patients who underwent electrophysiologic (EP) catheterization. FL was routinely avoided in all cases (54.2% males, age 57.2 ±â€¯13.3 years): 51 ablations and 19 EP study procedures. The Carto®3 (Biosense Webster) mapping system was used in 17/70 cases (24.3%), and the EnSite Precision™ (Abbott) system in the remaining 53/70 (75.7%). The mean procedure time was 94.1 ±â€¯33.2 min; no FL was used. No major complications occurred. Acute procedural success was achieved in all 51 patients who underwent ablation. Over 3-month follow-up, arrhythmia recurred in 1 patient. There were no significant differences in procedural times between the two mapping systems, except for the time dedicated to the full geometry creation, which was longer for the EnSite Precision™ system: 10 min (8.5-15 IQR) vs 8 min (5-10 IQR) for the Carto® system (p < 0.001) mainly due to the sub-diaphragmatic navigation. The following procedural steps were considered critical in order to safely avoid FL use: "loop" advancing of catheters, the use of a fixed intracardiac reference, His signal landmark centered maps and the careful acquisition of sub-diaphragmatic extracardiac geometry. CONCLUSIONS: A routine zero X-ray approach by means of electro-anatomic 3D mapping systems is safe and effective in right-atrium procedures. Some ad-hoc discussed procedural steps may enhance safety.

Long-term clinical outcome of patients who failed catheter ablation of atrial fibrillation.

AIMS: Left atrial ablation fails to prevent symptomatic recurrences of atrial fibrillation (AF) in 20-30% of patients up to 3 years of follow-up despite multiple procedures. Data are lacking on the long-term clinical outcome of those patients for whom the decision was taken to renounce performing further ablation procedures. METHODS AND RESULTS: In this multicentre study, 218 (34%) of 631 consecutive patients, who had undergone AF catheter ablation in the years 2001-11 for drug-refractory symptomatic AF, had symptomatic AF recurrences after 1.5 ± 0.6 procedures. Their long-term clinical outcome was assessed in March 2012 (minimum follow-up 1 year). At a mean of 5.1 ± 2.6 years since their last ablation, 82 (38%) patients improved, 103 (47%) remained unchanged and 33 (15%) worsened, but only 17 (8%) had such a severe impairment of their quality of life as to require atrioventricular junction ablation and pacing (#13) or cardiac surgery (#4); 22 (10%) patients had had adverse clinical events (death in five, heart failure in five, stroke and transient ischaemic cerebral attack in four, severe haemorrhage in four, pacemaker or implantable cardioverter-defibrillator implantation in seven) and 98 (45%) patients had developed permanent AF. Compared with patients without permanent AF, fewer patients with permanent AF improved (3% vs. 66%, P = 0.001) and more got worse (28% vs. 5%, P = 0.001). At multivariable logistic regression, single ablation procedure, left atrial diameter, persistent AF and time from the last ablation were independent predictors of permanent AF. CONCLUSION: More than 5 years after a failed AF ablation, a small minority of patients had such an impaired quality of life as to require non-pharmacological interventions. Almost half developed permanent AF, which significantly impaired quality of life. Permanent AF was more common in patients who had left atrial enlargement, history of persistent AF, longer follow-up, and had performed a single ablation procedure, thus hypothesizing that reablation could reduce the chronicization of arrhythmia. A low risk of stroke was observed in the long-term follow-up.

Improving atrial fibrillation detection in patients with implantable cardiac devices by means of a remote monitoring and management application.

BACKGROUND: Atrial fibrillation (AF) is common in patients with cardiac implantable electronic devices (CIED) and has been associated with an increased stroke risk. The aim of our project was to assess the clinical value of a web-based application, Discovery Link AFinder, in improving AF detection in CIED patients. METHODS AND RESULTS: Seven Italian hospitals performed an observational study consisting of four phases. During phase 1, expert nurses and cardiologists prospectively followed-up CIED patients via in-hospital examinations and remote monitoring, and classified clinically relevant events, particularly AF occurrence. During phase 2, Discovery Link AFinder was exploited to identify patients who had suffered AF in the previous 12 months through the systematic scanning of device data remote transmissions. Phases 3 and 4 were repetitions of phases 1 and 2, respectively, and were implemented 6 months after the previous phases. A total of 472 consecutive patients were included in phase 1; AF occurred in 170 patients, 61 of whom were identified as new AF patients. Evidence of AF during this phase prompted prescription of oral anticoagulation (OAC) therapy in 30 patients. In phase 2, AFinder uncovered new AF, unidentified in phase 1, in 54 patients and prompted implementation of OAC therapy in 11 patients. During phase 3, 30 new AF patients were identified by means of remote monitoring, while during phase 4, a further three AF patients were identified by AFinder only. CONCLUSIONS: The AFinder web-based software, applied on top of standard in-hospital and remote monitoring, improved AF detection and enabled OAC treatment to be undertaken.

Updated national multicenter registry on procedural safety of catheter ablation for atrial fibrillation.

INTRODUCTION: Despite catheter ablation (CA) becoming an accepted treatment option for symptomatic, drug-resistant atrial fibrillation (AF), safety of this procedure continues to be cause for concern. Aim of the present multicenter registry was to assess the incidence of early CA complications and detect their predictors in a contemporary, unselected AF population METHODS AND RESULTS: From January 1, 2011 to December 31, 2011, data from 2,323 consecutive patients who underwent CA (median age 60 [52-67]; 72.3% male) for AF in 29 Italian centers were collected. All major complications occurring to the patient from admission to 30th postprocedural day were recorded. No procedure-related death was observed. Major complications occurred in 94 patients (4.0%): 50 patients (2.2%) suffered vascular access complications; 12 patients (0.5%) developed cardiac tamponade; 14 patients (0.6%) presented with pericarditis; 5 patients (0.2%) had transient ischemic attack; 4 patients had stroke; 3 patients (0.1%) had phrenic nerve paralysis; 3 patients (0.1%) had hemothorax. Other isolated but serious adverse events were documented in 3 patients (0.1%). Female gender (OR 2.643; 95% CI 1.686-4.143; P < 0.0001) and longer procedural duration (OR 2.195; 95% CI 1.388-3.473; P < 0.001) independently predicted a higher risk of complications. CONCLUSION: Major complications occurred in 4.0% of the CA procedures for AF, with vascular access complications being the most frequent events.

Comparison of ThermoCool® Surround Flow catheter versus ThermoCool® catheter in achieving persistent electrical isolation of pulmonary veins: a pilot study.

INTRODUCTION: Aim of this study was to compare efficacy and safety of the new ThermoCool Surround Flow® catheter (SFc) versus the ThermoCool® (TCc) in achieving persistent circumferential electrical isolation of the pulmonary veins (PVs) in patients with paroxysmal atrial fibrillation (AF). METHODS AND RESULTS: This multicenter, randomized, controlled study enrolled patients suffering from paroxysmal AF. Randomization was run in a one-to-one fashion between radiofrequency ablation by TCc or SFc. Aim of PVs ablation was documentation of electrical isolation with exit/entrance block recorded on a circular catheter. Among the 106 enrolled patients, 52 (49.0%) were randomized to TCc and 54 (51.0%) to SFc. Total volume of infused saline solution during the procedure was lower in the SFc than in TCc group (752.7 ± 268.6 mL vs 1,165.9 ± 436.2 mL, P < 0.0001). Number of identified and isolated PVs was similar in the 2 groups. Number of PVs remaining isolated 30 minutes after ablation was higher in the SFc than in TCc group (95.2% vs 90.5%, P < 0.03), mainly driven by acute ablation result in the left PVs (96.1% vs 89.7%, P < 0.04). Complications were seldom and observed only in the TCc group (0% vs 3.84%, P < 0.03). At 6-month follow-up SFc patients reported a trend toward less AF recurrences compared to those in the TCc group (22.9% vs 27.0%, P = 0.69). CONCLUSION: PV isolation by SFc lowered the rate of left PV early reconnections and reduced the volume of infused saline solution while maintaining the safety profile of AF ablation.

Reduced fluoroscopy exposure during ablation of atrial fibrillation using a novel electroanatomical navigation system: a multicentre experience.

AIMS: Catheter ablation of atrial fibrillation (AF) focuses on pulmonary vein (PV) ablation with or without additional atrial substrate modification. These procedures require significant fluoroscopy exposure. A new 3D non-fluoroscopic navigation system (CARTO(®) 3 System, Biosense Webster, CA, USA) that allows precise location visualization of diagnostic and ablation catheters was evaluated for its impact on fluoroscopic exposure during AF ablation procedures. METHODS AND RESULTS: Two groups of patients were treated by our centres for drug refractory AF. One group was treated using the new CARTO(®) 3 system to guide catheter ablation (Group A, 117 patients). The other group was treated using the CARTO(®) XP system (Biosense Webster) 3 months previously (Group B, 123 patients). For both groups, circumferential PV ostia ablation was performed; PV isolation was validated using a circular catheter placed at each ostium. There was no difference in any clinical characteristics (age, sex, AF type, left atrium diameter and volume, and heart disease) among the two study groups. The mean number of PVs identified and isolated per patient was similar in both groups, as were the mean procedural duration and radiofrequency time. However, mean fluoroscopic time was significantly reduced in Group A (15.9±12.3 min) as compared with Group B (26±15.1 min) (P < 0.001). CONCLUSION: This multicentre observational study demonstrates a significant reduction of fluoroscopy exposure using a new 3D non-fluoroscopic mapping system to guide AF catheter ablation.

Straight screw-in atrial leads "J-post shaped" in right appendage versus J-shaped systems for permanent atrial pacing: a safety comparison.

BACKGROUND AND OBJECTIVES: The reliability of active-fixation atrial leads has been compared with that of passive-fixation leads; comparisons have also been made between straight and J-shaped screw-in lead systems. However, few data are available on procedural and short-term safety. This retrospective study compared the procedural safety of non-pre-shaped screw-in leads with that of passive- and active-fixation J-shaped leads. PATIENTS AND METHODS: From January 2004 to January 2010, 1,464 patients underwent new pacemaker/implantable cardioverter-defibrillator implantation. Of these, 915 (study population) received a passive- or active-fixation pre-J-shaped lead, or a straight screw-in atrial lead; the remaining 549 patients, who received only a ventricular lead, were excluded. The three study groups were: Group S-FIX (165 patients, 18%), receiving a straight screw-in atrial lead (postshaped in the right appendage); Group J-PASS (690 patients, 75.4%), receiving a passive-fixation J-shaped atrial lead; and Group J-FIX (60 patients, 6.6%), receiving an active-fixation screw-in J-shaped atrial lead. Procedural and short-term complication rates were analyzed up to 3 months postimplantation. RESULTS: One complication occurred in each group (S-FIX 0.6% vs J-PASS 0.1% vs J-FIX 1.6%, P = 0.3, 0.1, and 0.4, respectively, for each comparison). The rate of atrial lead dislodgement was higher in Group J-PASS than in S-FIX but not J-FIX (Group S-FIX 0 vs Group J-PASS 16 vs Group J-FIX 1 dislodgements; P = 0.04 and 0.7, respectively). CONCLUSION: Straight screw-in atrial leads, "J-post shaped" in the right appendage, offer better stability than passive-fixation J-shaped leads and display a similarly acceptable safety profile compared with both the J-shaped systems.

Electroanatomic voltage mapping and characterisation imaging for "right ventricle arrhythmic syndromes" beyond the arrhythmia definition: a comprehensive review.

Three-dimensional (3D) reconstruction by means of electroanatomic mapping (EAM) systems, allows for the understanding of the mechanism of focal or re-entrant arrhythmic circuits along with pacing techniques. However, besides this conventional use, EAM may offer helpful anatomical and functional information. Data regarding electromechanical scar detection in ischaemic (and nonischaemic) cardiomyopathy are mostly consolidated, while emerging results are becoming available in contexts such as arrhythmogenic right ventricular dysplasia (ARVC/D) definition and Brugada syndrome. As part of an invasive procedure, EAM has not yet been widely adopted as a stand-alone tool in the diagnostic path. We aim to review the current literature regarding the use of 3D EAM systems for right ventricle (RV) functional characterisation beyond the definition of arrhythmia.

Transcatheter ablation of the atrioventricular junction in refractory atrial fibrillation: A clinicopathological study.

BACKGROUND: Catheter ablation of the specialized atrioventricular junction (AVJ) with a right-side approach is an effective therapy for refractory atrial fibrillation with fast ventricular rate. Our aim is to assess the efficacy of the procedure in a single center experience and investigate the histologic findings of AVJ after catheter ablation. METHODS: A) Analysis of AVJ ablation efficacy in a consecutive series of patients with refractory atrial fibrillation; B) Histopathologic study of the conduction system by serial section technique and clinical-electrophysiologic correlation in four patients who underwent AVJ ablation. RESULTS: A) Right-sided AVJ ablation was successful in all 87 consecutive patients (mean procedural time 19.2±17.9 min). Energy applications ranged from 1 to 27 (mean 5.8±5.1) with eight patients (9%) requiring > 15 applications. B) Fibrotic disruption of atrioventricular (AV) node and/or His bundle interruption was found in three cases with previous AVJ ablation. In the case requiring a left side approach, the compact AV node and common His bundle appeared undamaged whereas extensive fibrosis of the summit of the ventricular septum, branching His bundle and proximal bundle branches was found. Noteworthy, a continuity between the septal and anterior tricuspid valve leaflets was present. CONCLUSION: Our data confirm that the ideal site for ablation of the specialized AVJ is the AV node. In selected cases with unsuccessful AV node ablation, a shift towards the His bundle is needed. A continuity between the septal and anterior leaflets of the tricuspid valve may protect the His bundle as to require multiple shocks and prolong the procedure.

Does catheter ablation cure atrial fibrillation? Single-procedure outcome of drug-refractory atrial fibrillation ablation: a 6-year multicentre experience.

Aims In the last decade, several approaches to ablating triggers and substrates of atrial fibrillation (AF) have been developed. However, most studies have reported data only on short- or medium-term follow-up. The aim of this study was to investigate whether the 1-year efficacy of catheter ablation for AF is predictive of long-term clinical success. Methods and results Between February 2001 and October 2003, 229 consecutive patients affected by drug-refractory paroxysmal or persistent AF underwent a single radiofrequency catheter ablation procedure (anatomical approach in 146 patients and electrophysiologically guided approach in 83 patients). Of these patients, 177 (mean age 59.1 +/- 10.5 years, 57.6% with paroxysmal AF) were free from any atrial arrhythmia recurrence after 12 months. These 177 patients were subsequently followed up for at least another 24 months, by means of electrocardiogram and 24 h Holter monitoring. After a mean follow-up of 49.7 +/- 13.3 months (range 36-83 months), 58.2% of the patients were free from any atrial arrhythmia recurrence (39.5% without antiarrhythmic drugs). The actuarial atrial arrhythmia recurrence rate was 13.0% at 2 years, 21.8% at 3 years, 35.0% at 4 years, 46.8% at 5 years, and 54.6% at 6 years. Atrial arrhythmia-free survival was similar in patients with paroxysmal or persistent AF, with and without antiarrhythmic drugs during the follow-up, who underwent electrophysiologically guided pulmonary vein (PV) isolation or anatomical PV ablation. Conclusion Even patients in whom catheter ablation prevents AF recurrence for 1 year should not be considered 'cured', since >40% of them will suffer AF recurrence over a long-term clinical follow-up.

Cardiac implantable electronic device remote monitoring in a large cohort of patients and the need for planning.

Aim: The remote monitoring (RM) of cardiac implantable electronic devices (CIED) is standard of care. We describe an organizational and projection RM workload model. Methods: At the time of the analysis (2015), 3995 CIED patients were followed-up; 1582 (40.5%) with RM. All RM transmissions (Tx) have been gathered in five event types. Results: We received 10,406 Tx, classified as: 128 (1.2%) red alerts, 141 (1.3%) atrial fibrillation episodes, 1944 (18.6%) yellow alerts, 403 (3.9%) lost Tx (disconnected/noncompliant patients) and 7790 (75.0%) Tx 'OK' (un-eventful Tx). At the time of 100% of remote CIED managed, we can expect a total of 25,990 Tx/year. Conclusion: We provide a descriptive analysis of remote monitoring management and workload estimation in a large cohort of CIED patients.

Daily Exposure to Air Pollution Particulate Matter Is Associated with Atrial Fibrillation in High-Risk Patients.

Several epidemiological studies found an association between acute exposure to fine particulate matter of less than 2.5 µm and 10 µm in aerodynamic diameter (PM2.5 and PM10) and cardiovascular diseases, ventricular fibrillation incidence and mortality. The effects of pollution on atrial fibrillation (AF) beyond the first several hours of exposure remain controversial. A total of 145 patients with implantable cardioverter-defibrillators (ICDs), cardiac resynchronization therapy defibrillators (ICD-CRT), or pacemakers were enrolled in this multicentric prospective study. Daily levels of PM2.5 and PM10 were collected from monitoring stations within 20 km of the patient's residence. A Firth Logistic Regression model was used to evaluate the association between AF and daily exposure to PM2.5 and PM10. Exposure levels to PM2.5 and PM10 were moderate, being above the World Health Organization (WHO) PM2.5 and PM10 thresholds of 25 µg/m3 and 50 µg/m3, respectively, on 26% and 18% of the follow-up days. An association was found between daily levels of PM2.5 and PM10 and AF (95% confidence intervals (CIs) of 1.34-2.40 and 1.44-4.28, respectively) for an increase of 50 µg/m3 above the WHO threshold. Daily exposure to moderate PM2.5 and PM10 levels is associated with AF in patients who are not prone to AF.

Image integration increases efficacy of paroxysmal atrial fibrillation catheter ablation: results from the CartoMerge Italian Registry.

AIMS: The aim of this study was to investigate whether circumferential pulmonary vein (PV) isolation guided by image integration improves the procedural and clinical outcomes of atrial fibrillation (AF) ablation in comparison with segmental PV isolation and circumferential PV isolation guided by three-dimensional (3D) electroanatomical mapping alone. METHODS AND RESULTS: Procedural and clinical outcomes of 573 patients who underwent their first catheter ablation for paroxysmal AF between January 2005 and April 2007 were collected from 12 centres. We evaluated three techniques: segmental ostial PV isolation (SOCA group, 240 patients), circumferential PV isolation guided by electroanatomical mapping (CARTO group, 107 patients), and circumferential PV isolation guided by electroanatomical mapping integrated with magnetic resonance/computed tomographic images of the left atrium (MERGE group, 226 patients). Procedure duration proved to be shorter in MERGE group patients than in CARTO group patients (P < 0.04), but longer than in SOCA group patients (P < 0.0001). During follow-up, atrial tachyarrhythmias relapsed more frequently in SOCA group patients (44.6%) and CARTO group patients (41.7%) than in MERGE group patients (22.6%; P < 0.0001). CONCLUSION: In patients with paroxysmal AF, circumferential PV isolation guided by image integration significantly improves clinical outcome in comparison with both circumferential PV isolation guided by 3D mapping alone and with segmental electrophysiologically guided PV isolation.