STereotactic Arrhythmia Radioablation (STAR): the Standardized Treatment and Outcome Platform for Stereotactic Therapy Of Re-entrant tachycardia by a Multidisciplinary consortium (STOPSTORM.eu) and review of current patterns of STAR practice in Europe.

The EU Horizon 2020 Framework-funded Standardized Treatment and Outcome Platform for Stereotactic Therapy Of Re-entrant tachycardia by a Multidisciplinary (STOPSTORM) consortium has been established as a large research network for investigating STereotactic Arrhythmia Radioablation (STAR) for ventricular tachycardia (VT). The aim is to provide a pooled treatment database to evaluate patterns of practice and outcomes of STAR and finally to harmonize STAR within Europe. The consortium comprises 31 clinical and research institutions. The project is divided into nine work packages (WPs): (i) observational cohort; (ii) standardization and harmonization of target delineation; (iii) harmonized prospective cohort; (iv) quality assurance (QA); (v) analysis and evaluation; (vi, ix) ethics and regulations; and (vii, viii) project coordination and dissemination. To provide a review of current clinical STAR practice in Europe, a comprehensive questionnaire was performed at project start. The STOPSTORM Institutions' experience in VT catheter ablation (83% ≥ 20 ann.) and stereotactic body radiotherapy (59% > 200 ann.) was adequate, and 84 STAR treatments were performed until project launch, while 8/22 centres already recruited VT patients in national clinical trials. The majority currently base their target definition on mapping during VT (96%) and/or pace mapping (75%), reduced voltage areas (63%), or late ventricular potentials (75%) during sinus rhythm. The majority currently apply a single-fraction dose of 25 Gy while planning techniques and dose prescription methods vary greatly. The current clinical STAR practice in the STOPSTORM consortium highlights potential areas of optimization and harmonization for substrate mapping, target delineation, motion management, dosimetry, and QA, which will be addressed in the various WPs.

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.

Stereotactic ablative radiotherapy in patients with refractory ventricular tachyarrhythmia.

Stereotactic ablative body radiotherapy (SABR) is an innovative therapeutic approach in patients (pts) with a diagnosis of refractory ventricular tachyarrhythmia (VT) after the use of drugs, radiofrequency catheter ablation, and/or defibrillator (ICD) implant. The current efficacy data of SABR are limited and several prospective clinical studies are ongoing to support the use of ablative radiation dose to control VT. The aim of the current prospective pilot study is to report the efficacy and tolerability of SABR in ICD implanted pts with refractory VT in our centre. Non-invasive electroanatomical mapping (EAM), cardiac computed tomography (CT), and 18F-fluorodeoxyglucose positron emission (FDG-PET)-CT scan were used and combined with a radiation CT scan. A dose prescription of 25 Gy in a single dose was delivered by volumetric modulated arc therapy (VMAT) Linac-based. The primary endpoint was efficacy, defined as a reduction in ICD shocks after SABR treatment, while the secondary endpoint was safety. Six consecutive pts (five males and one female) implanted with an ICD and with three or more VT were enrolled. One pts died after 1 month, due to end-stage heart failure. Two pts experienced ICD shocks in VT 2 and 5 months after treatment. Three pts experienced no more ICD shocks on VT after therapy. Our data suggest the efficacy and safety of SABR treatment in pts with VT. Larger dataset of pts and longer follow-up are otherwise required to validate the impact of SABR as a standardized treatment in these pts.

Cryoablation for pulmonary veins isolation in obese patients with atrial fibrillation compared to nonobese patients.

BACKGROUND: Pulmonary veins isolation (PVI) by cryoballoon (CB) ablation is marginally represented in clinical studies in obese patients. The aim of this analysis was to evaluate the safety and efficacy of CB-PVI in a large cohort of overweight and obese patients from the 1STOP project. METHODS: From 2012 to 2018, 2048 patients with atrial fibrillation (AF) (70% male, 59 ± 11 years; 75% paroxysmal AF) underwent index CB-PVI. The patient data were separated into three cohorts for statistical evaluation, including: normal weight (body mass index [BMI] < 25 kg/m2 ), overweight (BMI = 25-30 kg/m2 ), and obese patients (BMI > 30 kg/m2 ). RESULTS: Out of 2048 patients, 693 (34%) patients had a BMI < 25 and were deemed as normal. There were 944 (46%) patients categorized as overweight (BMI = 25-30) and 411 (20%) as obese (BMI > 30). Overweight or obese patients were more often in persistent AF, had more frequently hypertension and diabetes, had higher CHA2 DS2 -VASc score, and had a number of failed antiarrhythmic drug (AAD). Periprocedural complication rates were similar among the three cohorts. The 12-month freedom from AF recurrence was 76.4% in the normal BMI group as compared to 79.2% in the overweight and 73.5% in the obese group (p = .35). However, 48% of overweight patients were on AAD treatment during the follow-up. By multivariate analysis, BMI was not a predictor for AF recurrence following the index CB-PVI. CONCLUSION: CB-PVI in obese patients is a safe procedure. Increased BMI (either moderate or severe) does not seem to be associated with a worse outcome or to a different rate of AAD discontinuation at 12 months.

A comparison of acute procedural outcomes within four generations of cryoballoon catheters utilized in the real-world multicenter experience of 1STOP.

INTRODUCTION: Four generations of the cryoballoon (CB) catheter were retrospectively evaluated in a real-world examination of patients with atrial fibrillation (AF). METHODS AND RESULTS: Four hundred eighty patients (27% female and 60 ± 10 years) suffering from AF, underwent pulmonary vein (PV) ablation with one-of-four generations of the CB catheter. The total cohort was divided into four groups of patients: 120 with first-generation (CB-1); 120 with second-generation (CB-2); 120 with third-generation (CB-3); and 120 with fourth-generation (CB-4). Equal group sizes were achieved by examining the last 120 patients treated in each cohort, attempting to minimize the effect of a learning curve between the generations of CB catheter. Baseline clinical and patient characteristics were similar between the four cohorts, excepting age and the number of tested antiarrhythmic drugs. Procedure, fluoroscopy, and left atrial dwell times were significantly lower in the CB-4 cohort compared to previous generations of the CB catheters, while the acute procedural success rate was comparable across all catheter groups (>99%). Total acute procedural complications were low (2.5%), and acute complications were comparable within the CB-2, CB-3, and CB-4 groups (0.8% reported in each cohort). The rate of time-to-isolation (TTI) visualization increased with later generations of the CB catheters. CONCLUSIONS: The novel CB-4 achieved significantly faster procedural ablation times in comparison to the previous generations, while still maintaining a low rate of acute complications. Also, the rate of TTI visualization was observed to be higher with the CB-4 catheter. Further long-term evaluation is necessary, including an assessment of AF recurrence and PV reconnection(s).

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.

Cryoballoon or radiofrequency ablation? Alternating technique for repeat procedures in patients with atrial fibrillation.

BACKGROUND: Which technique is better for repeat ablation in patients with atrial fibrillation (AF) remains unclear. The aim of the study was to compare long-term efficacy of repeat ablation using the alternative technique for the first redo ablation procedure: (a) cryoballoon (CB) re-ablation after a failed index pulmonary vein isolation (PVI) with radiofrequency (RF) ablation, RF-then-CB group or (b) RF repeat ablation following a failed CB ablation, CB-then-RF group. METHODS: Within the 1STOP Italian Project, consecutive patients undergoing repeat ablation with a different technique from the index procedure were included. RESULTS: We studied 474 patients, 349 in RF-then-CB and 125 in CB-then-RF group. Less women (21% vs 30%; P = .041), more persistent AF (33% vs 22%; P = .015), longer duration of AF (60 vs 31 months; P < .001), and more hypertension (50% vs 36%; P = .007) were observed in the RF-then-CB cohort as compared with the CB-then-RF group. The number of reconnected PVs was 3.7 ± 0.7 and 1.4 + 1.3 in RF-then-CB and CB-then-RF group, respectively (P < .001). During the follow-up, significantly less AF recurrence occurred in the CB-then-RF group (22% vs 8%, HR = 0.46; 95% CI: 0.24-0.92; P = .025). Cohort designation was the only independent predictor of AF recurrence. CONCLUSION: Alternation of energy source for repeat ablation was safe and effective, regardless the energy used first. However, patients initially treated with CB PVI undergoing repeat ablation with RF current had less AF recurrence at long-term follow-up as compared with those originally treated by RF ablation receiving a CB repeat ablation.

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.

Coronary Sinus Ablation Is a Key Player Substrate in Recurrence of Persistent Atrial Fibrillation.

Atrial fibrillation (AF) is the most frequent atrial arrhythmia. During the last few decades, owing to numerous advancements in the field of electrophysiology, we reached satisfactory outcomes for paroxysmal AF with the help of ablation procedures. But the most challenging type is still persistent AF. The recurrence rate of AF in patients with persistent AF is very high, which shows the inadequacy of pulmonary vein isolation (PVI). Over the last few decades, we have been trying to gain insight into AF mechanisms, and have come to the conclusion that there must be some triggers and substrates other than pulmonary veins. According to many studies, PVI alone is not enough to deal with persistent AF. The purpose of our review is to summarize updates and to clarify the role of coronary sinus (CS) in AF induction and propagation. This review will provide updated knowledge on developmental, histological, and macroscopic anatomical aspects of CS with its role as arrhythmogenic substrate. This review will also inform readers about application of CS in other electrophysiological procedures.

TWARMI pilot trial: The value and optimal criteria of microvolt T-wave alternans in the diagnosis of reversible myocardial ischemia in patients without structural cardiac disease.

AIMS: Microvolt T-wave alternans (MTWA) testing is a beat-to-beat fluctuation in the amplitude of T wave. We investigated whether: (a) MTWA can be new non-invasive tool for detection of reversible ischemia in patients with suspected CAD without structural heart disease, (b) MTWA can detect ischemia earlier and with greater test accuracy compared with exercise ECG ST-segment testing, and (c) threshold value of MTWA and heart rate at which the alternans is estimated can be different compared to standard values. METHODS: A total of 101 patients with suspected stable coronary disease, but without structural heart disease, were included. Echocardiography, exercise ECG test, MTWA with classical and modified threshold alternans values, and coronary angiography were performed. RESULTS: About 33.3% patients had a false-positive result on exercise ECG test. The sensitivity of exercise ECG ST-segment test in the detection of coronary artery disease was 97.8%, and the specificity was 42.5% (DOR 33.89). In a group of angiographically positive patients, standard MTWA accurately identified 60% of patients, while 40% had a false-negative result. About 91.8% patients with negative angiography result were accurately identified with 8.2% false positives. The sensitivity of MTWA was 59.61% and specificity 91.83%. Best ratio of sensitivity and specificity (86.53% and 95.91%, DOR 151.06) had modified criteria for positive MTWA (MTWA >1.5 µV at heart rate 115-125/min). CONCLUSIONS: This study showed that MTWA can be the new non-invasive tool for the detection of reversible ischemia in patients with suspected CAD without structural heart disease. Also, MTWA can detect ischemia earlier and with greater accuracy compared with exercise ECG testing.

The increased risk of stroke/transient ischemic attack in women with a cardiac implantable electronic device is not associated with a higher atrial fibrillation burden.

AIMS: To evaluate if the increased thromboembolic risk in female patients may be related to a higher burden of atrial fibrillation (AF). METHODS AND RESULTS: Data collected in a prospective observational research of patients implanted with a cardiac implantable electrical device (CIED) were analysed. We included 2398 patients: 489 (20.4%) were female and 1909 (79.6%) were male (oral anticoagulants treatment in 23.2%, independent of gender). During the follow-up (mean 42.8, median 37.7 months), 26 thromboembolic events occurred in 22 patients, with an incidence rate ratio of both stroke and stroke/transient ischemic attack (TIA) significantly higher in females compared with males [2.00, 95% confidence interval (CI) 1.53-2.61, P< 0.001 for stroke; 1.77 (95% C1.37-2.31, P< 0.001 for stroke/TIA]. An AF burden ≥5 min was a common finding (44% of patients), with no difference between men and women. The maximum daily AF burden and the time to evolution in permanent AF did not differ according to gender. The results of multivariate Cox regression showed that female gender, as well as history of CABG, were significant independent predictors of stroke and female gender was also an independent predictor of stroke/TIA. CONCLUSIONS: Among patients implanted with a CIED, an AF burden of at least 5 min is a common finding, (44% of patients). Female patients have a risk of stroke and TIAs that is around two-fold that of male patients, but this increased risk cannot be ascribed to a higher burden of AF or to differences in the evolution to permanent AF. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01007474.

ANMCO/AIAC/SICI-GISE/SIC/SICCH Consensus Document: percutaneous occlusion of the left atrial appendage in non-valvular atrial fibrillation patients: indications, patient selection, staff skills, organisation, and training.

Atrial fibrillation (AF) is the most common arrhythmia and its prevalence is increasing due to the progressive aging of the population. About 20% of strokes are attributable to AF and AF patients are at five-fold increased risk of stroke. The mainstay of treatment of AF is the prevention of thromboembolic complications with oral anticoagulation therapy. Drug treatment for many years has been based on the use of vitamin K antagonists, but recently newer and safer molecules have been introduced (dabigatran etexilate, rivaroxaban, apixaban, and edoxaban). Despite these advances, many patients still do not receive adequate anticoagulation therapy because of contraindications (relative and absolute) to this treatment. Over the last decade, percutaneous closure of left atrial appendage, main site of thrombus formation during AF, proved effective in reducing thromboembolic complications, thus offering a valid medical treatment especially in patients at increased bleeding risk. The aim of this consensus document is to review the main aspects of left atrial appendage occlusion (selection and multidisciplinary assessment of patients, currently available methods and devices, requirements for centres and operators, associated therapies and follow-up modalities) having as a ground the significant evolution of techniques and the available relevant clinical data.

Reduction of inappropriate anti-tachycardia pacing therapies and shocks by a novel suite of detection algorithms in heart failure patients with cardiac resynchronization therapy defibrillators: a historical comparison of a prospective database.

AIMS: Implantable cardioverter defibrillators improve survival of patients at risk for ventricular arrhythmias, but inappropriate shocks occur in up to 30% of patients and have been associated with worse quality of life and prognosis. In heart failure patients with cardiac resynchronization therapy defibrillators (CRT-Ds), we evaluated whether a new generation of detection and discrimination algorithms reduces inappropriate shocks. METHODS AND RESULTS: We analysed 1983 Medtronic CRT-D patients (80% male, 67 ± 10 years), 1368 with standard devices (Control CRT-D) and 615 with new generation devices (New CRT-D). Expert electrophysiologists reviewed and classified the electrograms of all device-detected ventricular tachycardia/fibrillation episodes. Total follow-up was 3751 patients-years. Incidence of inappropriate shocks at 1 year was 2.8% [95% confidence interval (CI) = 2.0-3.5] in Control CRT-D and 0.9% (CI = 0.4-2.2) in New CRT-D (hazard ratio = 0.37, CI = 0.21-0.66, P < 0.001). In New CRT-D, inappropriate shocks were reduced by 77% [incidence rate ratio (IRR) = 0.23, CI = 0.16-0.35, P < 0.001] and inappropriate anti-tachycardia pacing by 81% (IRR = 0.19, CI = 0.11-0.335, P < 0.001). Annual rate per 100 patient-years for appropriate VF detections was 3.0 (CI = 2.1-4.2) in New CRT-D and 3.2 (CI = 2.1-5.0) in Control CRT-D (P = 0.68), for syncope was 0.4 (CI = 0.2-0.9) in New CRT-D and 0.7 (CI = 0.5-1.0) in Control CRT-D (P = 0.266), and for death was 1.0 (CI = 0.6-1.6) in New CRT-D and 3.5 (CI = 3.0-4.1) in Control CRT-D (P < 0.001). CONCLUSION: Detection and discrimination algorithms used in new generation CRT-D significantly reduced inappropriate shocks when compared with standard CRT-D. This result, with no compromise on VF sensitivity or risk of syncope, has important implications for patients' quality of life and prognosis.

Prospective Use of Microvolt T-Wave Alternans Testing to Guide Primary Prevention Implantable Cardioverter Defibrillator Therapy.

BACKGROUND: We hypothesized that a negative microvolt T-wave alternans (MTWA) test would identify patients unlikely to benefit from primary prevention implantable cardioverter defibrillator (ICD) therapy in a prospective cohort. METHODS AND RESULTS: Data were pooled from 8 centers where MTWA testing was performed specifically for the purpose of guiding primary prevention ICD implantation. Cohorts were included if the ratio of ICDs implanted in patients who were MTWA "non-negative" to patients who were MTWA negative was >2:1, indicating that MTWA testing had a significant impact on the decision to implant an ICD. The pooled cohort included 651 patients: 371 MTWA non-negative and 280 MTWA negative. Among non-negative patients, 62% underwent ICD implantation whereas only 13% of MTWA-negative patients received an ICD (P<0.01). Despite a substantially lower prevalence of ICDs, long-term survival (6.9 years) was significantly better among MTWA-negative patients (68.2% non-negative vs. 87.1% negative, P=0.026). CONCLUSIONS: MTWA-negative patients had significantly better survival than MTWA non-negative patients, the majority of whom had ICDs. Despite a very low prevalence of ICDs, long-term survival among patients with left ventricular ejection fraction ≤40% and a negative MTWA test was better than in the ICD arm of any study to date that has demonstrated a benefit of ICDs. This provides further evidence that MTWA-negative patients are unlikely to benefit from primary prevention ICD therapy.

One Year Incidence of Atrial Septal Defect after PV Isolation: A Comparison Between Conventional Radiofrequency and Cryoballoon Ablation.

BACKGROUND: Transseptal (TS) catheterization is needed to access the left heart during pulmonary vein isolation (PVI) procedures. In the radiofrequency (RF) ablation procedure, left atrial access is commonly achieved with a double TS puncture; cryoballoon (CB) ablation usually requires only a single TS puncture. Our aim was to compare the incidence of iatrogenic septal defect (IASD) between double transseptal conventional RF and CB ablation. METHODS AND RESULTS: Individuals having undergone PVI as index procedure by RF or CB ablation and a subsequent transesophageal echocardiography examination during postablation follow-up in our center were consecutively included. A total of 127 patients formed the study group (92 males; mean age 60 ± 11 years). IASD was present in 17 patients (13.4%) after a mean follow-up time of 11.6 months. The incidence of IASD at 1-year follow-up following PVI was significantly higher in the CB ablation group compared with the RF ablation group (22.2% vs 8.5%; P = 0.03). Mean IASD diameter was larger in the CB group (0.60 cm × 0.50 cm vs 0.44 cm × 0.35 cm) without statistical significance. Only left to right atrial shunt was observed. No adverse events were recorded in these patients during the follow-up. CONCLUSIONS: the incidence of IASD at 1-year follow-up following CB ablation procedure for PVI is significantly higher with respect to RF procedures. Although no adverse clinical events were recorded in patients with persistence of IASD, more detailed echocardiographic examinations might be advised in all individuals exhibiting this finding.

Incremental value of larger interventricular conduction time in improving cardiac resynchronization therapy outcome in patients with different QRS duration.

INTRODUCTION: The left ventricular (LV) pacing site and the magnitude of the electrical delay within the LV, as expressed by prolonged QRS duration, are major determinants of cardiac resynchronization therapy (CRT) efficacy. We investigated the incremental value of positioning the LV lead in areas of late activation in order to enhance the response to CRT in patients with different degrees of QRS complex lengthening. METHODS AND RESULTS: This analysis was performed on 301 heart failure patients who received a CRT defibrillator. On implantation, the right ventricular (RV)-to-LV interval was measured as the delay between local activations recorded through the RV and LV leads in the final position. After 1 year, 171 (57%) patients displayed reverse LV remodeling, as measured by a ≥15% reduction in the LV end-systolic volume. Both the RV-to-LV interval and its percentage value corrected for the QRS duration were significantly associated with a positive response to CRT. An RV-to-LV interval >80 milliseconds and an RV-to-LV interval/QRS >58% yielded the best prediction of reverse remodeling. Although the response to CRT decreased with shorter QRS duration in the overall population, patients with an RV-to-LV interval >80 milliseconds showed a response rate >65% in all QRS subgroups. CONCLUSION: A longer RV-to-LV interval is associated with reverse LV remodeling after CRT. On implantation attempts could be made to maximize it when selecting the LV lead position, especially in patients with shorter QRS duration, and thus less likely to respond positively to CRT.

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.