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This study evaluated the temporal association between atrial high-rate episodes (AHREs) and sustained ventricular arrhythmias (VAs) in a remotely monitored cohort with implantable cardioverter-defibrillators (ICD) with and/or without cardiac resynchronization therapy with a defibrillator (CRT-D).Clinical relevance of AHREs in terms of VA rate and survival has not been outlined yet.This study analyzed data of patients with ICDs and CRT-Ds from the nationwide Home Monitoring Expert Alliance network. The cohort included 2,435 patients with a median follow-up of 25 months (interquartile range: 13 to 42 months) and age 70 years (range 61 to 77 years); 19.7% were women, 51.4% had coronary artery disease, and 45.2% had a CRT-D. There were 3,410 appropriate VA episodes; 498 (14.6%) were preceded by AHREs within 48 h; in 85.5% of this group, AHREs were still ongoing at episode onset.In a longitudinal analysis, the odds ratios (ORs) of experiencing any VA in a 30-day interval with AHREs versus intervals without AHREs were 2.35 (95% confidence interval [CI]: 1.86 to 2.97; p 0.001) for ventricular tachycardia (VT), 3.06 (95% CI: 2.35 to 3.99; p 0.001) for fast VT, 1.84 (95% CI: 1.36 to 2.48; p 0.001) for self-extinguishing ventricular fibrillation (VF), and 2.31 (95% CI: 1.17 to 4.57; p = 0.01) for VF. ORs decreased with increasing AHRE burden. Patients with AHREs 48 h before VAs were more likely to experience VA recurrences (adjusted hazard ratio [HR]: 1.78; 95% CI: 1.41 to 2.24; p 0.001) and had higher overall mortality (HR: 2.67; 95% CI: 1.68 to 4.23; p 0.001).AHREs were not uncommon 48 h before VAs, which tended to be distributed around intervals with AHREs. Temporal connection between AHREs and VAs was a marker of increased risk of VA recurrence and a poorer prognosis.

INTRODUCTION Factors influencing malignant arrhythmia onset are not fully understood. We explored the circadian periodicity of ventricular arrhythmias (VAs) in patients with implantable cardioverter and cardiac resynchronization defibrillators (ICD/CRT-D). METHODS Time, morphology (monomorphic/polymorphic), and mode of termination (anti-tachycardia pacing [ATP] or shock) of VAs stored in a database of remote monitoring data were adjudicated. Episodes were grouped in six 4-h timeslots from 00:00 to 24:00. Circadian distributions and adjusted marginal odds ratios (ORs), with 95% confidence interval (CI), were analyzed using mixed-effect models and logit generalized estimating equations, respectively, to account for within-subject correlation of multiple episodes. RESULTS Among 1303 VA episodes from 446 patients (63% ICD and 37% CRT-D), 120 (9%) self-extinguished, and 842 (65%) were terminated by ATP, 343 (26%) by shock. VAs clustered from 08:00 to 16:00 with 44% of episodes, as compared with 22% from 00:00 to 08:00 (p

Background Undiagnosed sinus or atrioventricular node dysfunction may bias estimation of the real efficacy of cardiac pacing in preventing vasovagal reflex syncope. We assessed this hypothesis in the BIOSync CLS trial which showed that dual-chamber pacing with closed loop stimulation (CLS) remarkably reduced recurrences of syncope. Methods and results In the study patients aged 40 years or older with ≥2 episodes of loss of consciousness in the last year and an asystolic response to Tilt-Table test were randomized to pacing ON (DDD-CLS mode) or pacing OFF (ODO mode). We utilized the available pacemaker diagnostic data in a total of 103 patients (52 pacing ON, 51 pacing OFF) to generate cumulative distribution charts for heart rate (HR) and percentage of pacing. At 12 months, we did not find evidence of suspected sinus or atrioventricular node dysfunction. Beats were similarly distributed between groups (p = 0.96), with an average HR of 76 ± 8 bpm (pacing ON) versus 77 ± 7 bpm (pacing OFF). In the active group, the median percentage of atrial and ventricular pacing was 47% and 0%, respectively. Intolerance to high pacing rates was reported in only one patient (1.6%) and was easily resolved by reprogramming the maximum CLS pacing rate. Conclusions We did not find evidence of suspected sinus or atrioventricular node dysfunction in the BIOSync CLS patients. The benefit of pacing should be ascribed to pacing prevention of pure vasovagal episodes. CLS algorithm modulated pacing rates over a wide frequency range, consistently competing with sinus node.

Aim The benefit of cardiac pacing in patients with severe recurrent reflex syncope and asystole induced by tilt testing has not been established. The usefulness of tilt-table test to select candidates for cardiac pacing is controversial. Methods and results We randomly assigned patients aged 40 years or older who had at least two episodes of unpredictable severe reflex syncope during the last year and a tilt-induced syncope with an asystolic pause longer than 3 s, to receive either an active (pacing ON; 63 patients) or an inactive (pacing OFF; 64 patients) dual-chamber pacemaker with closed loop stimulation (CLS). The primary endpoint was the time to first recurrence of syncope. Patients and independent outcome assessors were blinded to the assigned treatment. After a median follow-up of 11.2 months, syncope occurred in significantly fewer patients in the pacing group than in the control group [10 (16%) vs. 34 (53%); hazard ratio, 0.23; P = 0.00005]. The estimated syncope recurrence rate at 1 year was 19% (pacing) and 53% (control) and at 2 years, 22% (pacing) and 68% (control). A combined endpoint of syncope or presyncope occurred in significantly fewer patients in the pacing group [23 (37%) vs. 40 (63%); hazard ratio, 0.44; P = 0.002]. Minor device-related adverse events were reported in five patients (4%). Conclusion In patients aged 40 years or older, affected by severe recurrent reflex syncope and tilt-induced asystole, dual-chamber pacemaker with CLS is highly effective in reducing the recurrences of syncope. Our findings support the inclusion of tilt testing as a useful method to select candidates for cardiac pacing. Study registration ClinicalTrials.gov identifier NCT02324920, Eudamed number CIV-05-013546.

Aims There are conflicting data on the benefit of cardiac resynchronization therapy (CRT) in heart failure (HF) patients with permanent atrial fibrillation (AF). We aimed to compare patient outcomes according to the presence or absence of permanent AF at device implantation. Methods and results We retrospectively analysed remote monitoring data from 1141 CRT defibrillators. Propensity score with inverse‐probability weighting method was used to balance AF and sinus rhythm (SR) groups. Analysis endpoints included total mortality, appropriate defibrillation shocks, and CRT percentage. There were 229 patients (20.1%) in the AF group and 912 patients (79.9%) in the SR group. Compared with SR patients, AF patients were older (median age, 77 vs. 72 years, P

Aims We developed and validated an algorithm for prediction of heart failure (HF) hospitalizations using remote monitoring (RM) data transmitted by implanted defibrillators. Methods and results The SELENE HF study enrolled 918 patients (median age 69 years, 81% men, median ejection fraction 30%) with cardiac resynchronization therapy (44%), dual-chamber (38%), or single-chamber defibrillators with atrial diagnostics (18%). To develop a predictive algorithm, temporal trends of diurnal and nocturnal heart rates, ventricular extrasystoles, atrial tachyarrhythmia burden, heart rate variability, physical activity, and thoracic impedance obtained by daily automatic RM were combined with a baseline risk-stratifier (Seattle HF Model) into one index. The primary endpoint was the first post-implant adjudicated HF hospitalization. After a median follow-up of 22.5 months since enrolment, patients were randomly allocated to the algorithm derivation group (n = 457; 31 endpoints) or algorithm validation group (n = 461; 29 endpoints). In the derivation group, the index showed a C-statistics of 0.89 [95% confidence interval (CI): 0.83–0.95] with 2.73 odds ratio (CI 1.98–3.78) for first HF hospitalization per unitary increase of index value (P Conclusion With the developed algorithm, two-thirds of first post-implant HF hospitalizations could be predicted timely with only 0.7 false alerts per patient-year.

Funding Acknowledgements This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Background/Introduction: Parameters routinely measured during cardiac devices implantation also depend on bioelectrical properties of the myocardial tissue. Purpose To explore the potential association of electrical parameters with clinical outcomes in implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy defibrillators (CRT-D) recipients. Methods In the framework of the Home Monitoring Expert Alliance, baseline electrical parameters for all implanted leads were compared by occurrence of all-cause mortality, adjudicated ventricular arrhythmia (VA) and atrial high rate episode lasting ≥7 days (7day-AHRE). Results In a cohort of 2,976 patients (58.1% ICD) with a median follow-up of 25 months, events rates were 3.1/100 patient-years for all-cause mortality, 18.1/100 patient-years for VA and 8.9/100 patient-years for 7day-AHRE. At univariate analysis baseline shock impedance was consistently lower in groups with events than in those without, with a 40 Ohm cut-off better identifying patients at high risk, but at multivariable analysis the adjusted-hazard ratios (HRs) lost statistical significance for any endpoint. Baseline atrial sensing amplitude during sinus rhythm was lower in patients with 7-day AHRE as compared to those without (2.40 [IQ: 1.62-3.71] Vs 3.50 [IQ: 2.35-4.66] mV, p 1.5 mV versus those with values ≤1.5 mV was 0.44 (95% CI:0.27-0.72), p = 0.001. Conclusion Despite in patients with events a lower baseline shock impedance was observed at univariate analysis, the association lost statistical significance at multivariable analysis. Conversely, low sinus rhythm atrial sensing (≤1.5 mV) measured with standard transvenous leads could identify subjects at high risk of long-lasting atrial arrhythmia. Abstract Figure. AHRE occurrence by atrial sensing

Aims A validated risk stratification schema for transvenous lead extraction (TLE) could improve the management of these procedures. We aimed to derive and validate a scoring system to efficiently predict the need for advanced tools to achieve TLE success. Methods and results Between November 2013 and March 2018, 1960 leads were extracted in 973 consecutive TLE procedures in two national referral sites using a stepwise approach. A procedure was defined as advanced extraction if required the use of powered sheaths and/or snares. The study population was a posteriori 1:1 randomized in derivation and validation cohorts. In the derivation cohort, presence of more than two targeted leads (odds ratio [OR] 1.76, P = 0.049), 3-year-old (OR 3.04, P = 0.001), 5-year-old (OR 3.48, P Conclusion In this study, we developed and tested a simple point-based scoring system able to efficiently identify patients at low and high risk of needing advanced tools during TLE procedures.

Background Parameters measured during implantable cardioverter defibrillator (ICD) implant also depend on bioelectrical properties of the myocardium. We aimed to explore their potential association with clinical outcomes in patients with single/dual‐chamber ICD and cardiac resynchronization therapy defibrillator (CRT‐D). Methods In the framework of the Home Monitoring Expert Alliance, baseline electrical parameters for all implanted leads were compared by the occurrence of all‐cause mortality, adjudicated ventricular arrhythmia (VA), and atrial high‐rate episode lasting ≥24 hours (24 h AHRE). Results In a cohort of 2976 patients (58.1% ICD) with a median follow‐up of 25 months, event rates were 3.1/100 patient‐years for all‐cause mortality, 18.1/100 patient‐years for VA, and 9.3/100 patient‐years for 24 h AHRE. At univariate analysis, baseline shock impedance was consistently lower in groups with events than without, with a 40 Ω cutoff that better identified high‐risk patients. However, at multivariable analysis, the adjusted‐hazard ratios (HRs) lost statistical significance for any endpoint. Baseline atrial sensing amplitude during sinus rhythm was lower in patients with 24 h AHRE than in those without (2.45 [IQR: 1.65‐3.85] vs 3.51 [IQR: 2.37‐4.67] mV, P 1.5 mV vs those with values ≤1.5 mV was 0.52 (95% CI: 0.33‐0.83), P = .006. Conclusions Although lower baseline shock impedance was observed in patients with events, the association lost statistical significance at multivariable analysis. Conversely, low sinus rhythm atrial sensing (≤1.5 mV) measured with standard transvenous leads could identify subjects at high risk of atrial arrhythmia., Some of the electrical parameters routinely measured at ICD/CRT‐D implant differed according to long‐term clinical outcome. Shock impedance values were lower in patients who experienced death and both atrial and ventricular arrhythmias during follow‐up. Subjects with atrial signal amplitude below 1.5 mV showed a significant higher risk of atrial arrhythmias as compared to those with >1.5 mV, potentially revealing the presence of a more impaired atrial tissue.

Background CHA2DS2-VASc is a validated score for predicting stroke in patients with atrial fibrillation (AF). Objective The purpose of this study was to assess whether the CHA2DS2-VASc score can predict new-onset AF in a cohort of patients with a cardiac implantable electronic device (CIED) followed with remote monitoring. Methods Using the database of the Home Monitoring Expert Alliance project, we selected 2410 patients with no documented AF who had received a CIED with diagnostics on atrial high rate episodes (AHREs). The primary endpoint was time to first day with cumulative AHRE burden ≥15 minutes, 5 hours, 24 hours, and ≥7 consecutive days. Results During a median duration of 24.1(11.5–42.9) months, the incidence of AHRE increased with increasing CHA2DS2-VASc. At 6 years, occurrence of ≥15-minute AHRE was 80.2% (CHA2DS2-VASc ≤1) vs 93.7% (CHA2DS2-VASc ≥5), whereas ≥5-hour AHRE incidence was 68.4% (CHA2DS2-VASc ≤1) vs 92.5% (CHA2DS2-VASc ≥5). Occurrence of ≥24-hour and ≥7-day AHREs also increased with increasing CHA2DS2-VASc: 9.1% and 3.9% (CHA2DS2-VASc ≤1) vs 40.4% and 28.7% (CHA2DS2-VASc ≥5), respectively. Adjusted hazard ratio for unitary CHA2DS2-VASc increase ranged from 1.09 (confidence interval 1.04–1.14; P

Objectives This study sought to compare the Intrinsic Rhythm Support (IRSplus) and Ventricular Pace Suppress (VpS) in terms of right ventricular pacing percentage (VP %), mean atrioventricular interval (MAVI), atrial fibrillation, and cardiac volumes. Background Modern pacemakers are provided with algorithms for reducing unnecessary ventricular pacing. These may be classified as: periodic search for intrinsic atrioventricular (AV) conduction prolonging the AV delay accordingly; or DDD-ADI mode switch. The IRSplus and VpS algorithms belong to the former and latter classes, respectively. Methods Patients with sick sinus dysfunction without evidence of II/III degree AV block were 1:1 randomized to 6-month periods of either IRSplus or VpS, and then crossed over. Subsequent follow-ups were at the 12th month after randomization for device data retrieving, and at the 18th month with the same device programming for echocardiographic assessment. Results A total of 230 patients (62% males, median age 75 years [interquartile range: 69 to 79 years]) were enrolled. At a linear mixed-model analysis with order of treatment and investigational sites as nested random effects, differences in VP% and MAVI reached statistical significance: VP% was 1% (0% to 11%) during IRSplus and 3% (0% to 26%) during VpS (p = 0.029); MAVI was 225 ms (198 to 253 ms) during IRSplus and 214 ms (188 to 240 ms) during VpS (p = 0.014). No differences were observed in atrial fibrillation burden and incidence, ejection fraction, and cardiac volumes. Conclusions Both IRSplus and VpS algorithms ensured VP% ≤3% in most patients with sinus node dysfunction and preserved AV conduction. The IRSplus was slightly more efficient in reducing VP% at the expense of a small MAVI increase, with statistical but clinically insignificant differences. (Ventricular Pace Suppression Versus Intrinsic Rhythm Support Study; NCT01528657 )

Background/Introduction The lack of a validated method to efficiently combine information provided by Remote Monitoring (RM) of implantable defibrillators (ICD) and patient clinical profile has limited the use of RM in the prevention of worsening heart failure episodes. Purpose Our objective was to develop and validate an index combining RM temporal trends and a baseline risk score for predicting the first HF hospitalization after device implantation. Methods We prospectively enrolled 918 patients (81% male, median age 69, interquartile interval [QI], 61/76; Seattle Heart Failure Score [SHFS], 0.17, QI, −0.40/0.75) with indication to ICD (56%), or ICD with cardiac resynchronization therapy (44%). The Home Monitoring (HM) system was activated in all patients after implant to collect several technical and HF-related variables daily. Investigators were blinded to HM reports, and only received automatic alerts for critical technical issues. The primary endpoint was the first adjudicated HF hospitalization. The cohort was a posteriori 1:1 randomized in derivation and validation groups stratified by device type and primary endpoint occurrence. The SHFS was used for baseline risk assessment. Results During a median follow-up of 23 months (QI, 14/36), 62 first HF hospitalizations were adjudicated. In the derivation group, the index was constructed by combining the SHFS and temporal trends of 24-hour and rest mean heart rates, ventricular ectopic beat frequency, arrhythmic atrial burden, heart rate variability, physical exercise, and thoracic impedance. Variable selection was based on an automatic stepwise procedure, after applying appropriate transformations in variable-specific time frames to maximize the area under the receiver operating characteristics curve (AUC). The resulting index was associated to an AUC of 0.88 and an Odds Ratio of 2.72 (confidence interval [CI] 1.97–3.75, p Conclusion HM temporal trends of selected variables and the SHFS may be combined to timely and efficiently predict the first HF hospitalization after implant, with less than 1 expected per-patient false alert per year. Acknowledgement/Funding BIOTRONIK SE & Co. KG, Berlin, Germany

Background: The occurrence of sustained ventricular arrhythmias (SVA) may be influenced by environmental factors. We aimed to investigate annual periodic trends of SVA from the intracardiac electrograms (IEGMs) stored in the implantable defibrillators (ICDs) or cardiac resynchronization therapy (CRT-D) recipients.Methods: Data from the Home Monitoring Expert Alliance project, a pooled repository of remote monitoring transmissions were analyzed. All IEGMs stored were independently adjudicated by three cardiac electrophysiologists. Periodicity of SVA was evaluated with Generalized Estimating Equations (GEE) models, including periodic terms depending on months in a year.Results: A total of 2936 ICD/CRT-D patients (median age 70 years, 79.6% male) were followed for a median period of 25[13-44] months. Most prevalent structural heart diseases were ischemic (50.8%) and idiopathic dilated (30.6%) cardiomyopathies. Overall, 942 (32.1%) patients experienced a total of 4824 SVA. At GEE analysis, we found a significant periodic component (p=0.048) when considering both shocked and non-shocked episodes. SVA less frequently occurred in Junes and Julies (3.7 x 1000 patient-month). No evidence of significant periodicity was collected in the subgroup of ischemic patients.Conclusions: In thisRM-based cohort of ICD/ CRT-T patients, we observed an annual periodicity of SVA occurrence, with a lower incidence in summer months. (c) 2018 Elsevier B.V. All rights reserved.

Background The role of atrial rate‐responsive (RR) pacing in cardiac resynchronization therapy (CRT) is unclear due to the favorable effect of rate lowering in systolic heart failure. Atrial high rate episodes (AHREs) in CRT recipients are particularly worrisome since they cause loss of CRT, beyond representing a stroke risk factor. Hypothesis The presence of an association between RR and the incidence of AHREs. Methods Daily remote transmissions from 836 CRT recipients were analyzed. AHREs were classified by duration: ≥15 minutes, ≥5 hours, and ≥ 24 hours. Variables possibly associated to AHREs were included in time‐dependent proportional‐hazard models, averaging over 30‐day periods and adjusting for main baseline variables. Results After a median follow‐up of 23.9 (12.2‐36.0) months, 507 (60.6%) patients experienced at least one 15‐minute AHRE. RR function was programmed in 166 (19.8%) patients and was associated with an increased AHRE occurrence rate with hazard ratio (HR) ranging from 1.45 to 1.78 for the 3 cutoffs of episode duration. The negative effect of RR function was not observed in the subset of patients with low mean heart rate ( 68 bpm is attained.

Introduction Clinical trials did not provide conclusive evidence concerning the benefit of prophylactic implantable cardioverter-defibrillators (ICDs) in patients with severe nonischemic cardiomyopathy (NICM). We aimed to compare incidence of appropriate sustained ventricular arrhythmia (SVA) and device therapy in ischemic cardiomyopathy (ICM) vs NICM ICD and/or cardiac resynchronization therapy (CRT-D) patients. Methods and results We analyzed remote-monitoring data from devices of the Home Monitoring Expert Alliance network. SVA recordings were adjudicated by three independent electrophysiologists. Our cohort included 1,946 patients who received either an ICD (55%) or a CRT-D (45%) for primary prevention of sudden cardiac death. Median (interquartile range) age was 70 (62-77) years, 81% were male, and 52% were in the ICM group. Patients were remotely monitored for a maximum follow-up of 5 years. The 5-year product-limit estimate of SVA incidence in patients with an ICD was 47.3% (95% confidence interval [CI], 41.0%-53.9%) in the ICM group and 44.7% (36.9%-53.3%) in the NICM group. In patients with a CRT-D, SVA incidence was 45.7% (37.3%-55.0%) in ICM patients and 49.2% (40.4%-58.7%) in NICM patients. The adjusted hazard ratio for SVA in the ICM vs NICM group was 0.96 (95% CI: 0.70-1.30, P = .77) in ICD patients and 0.85 (95% CI: 0.61-1.18, P = .34) in CRT-D patients. SVAs triggered appropriate device therapies with similar incidence in all groups. Conclusion In a large cohort of remotely monitored ICD and CRT-D recipients, SVA incidence did not significantly differ in ICM and NICM patients.

BACKGROUND: The rate of device replacement in pacemaker recipients has not been investigated in detail. HYPOTHESIS: Current pacemakers with automatic management of atrial and ventricular pacing output provide sufficient longevity to minimize replacement rate. METHODS: We considered a cohort of 542 pacemaker patients (age 78 ± 9 years, 60% male, 71% de‐novo implants) and combined 1‐month projected device longevity with survival data and late complication rate in a 3‐state Markov model tested in several Monte Carlo computer simulations. Predetermined subgroups were: age < or ≥ 70; gender; primary indication to cardiac pacing. RESULTS: At the 1‐month follow‐up the reported projected device longevity was 153 ± 45 months. With these values the proportion of patients expected to undergo a device replacement due to battery depletion was higher in patients aged

Purpose: Benefit of cardiac pacing in patients with vasovagal syncope (VVS) and cardioinhibitory response to head-up tilt test (HUTT) is still debated. We aimed at retrospectively assessing the long-term effect of cardiac pacing in a cohort routinely followed in our institutions.Methods and results: From a cohort of 1502 patients who performed HUTT between 2008 and 2014, 181 (12%) patients had VASIS 2A (40) or 2B (141) response (median age 43 [interquartile range, 25-56] years, 59% male). Fifty patients (28%) received a dual-chamber pacemaker and 131 (72%) received training on physical maneuvers and medical therapy. The so-called 'Closed Loop Stimulation' (CLS) function was activated for at least 18 months in the pacing group. The 5-year recurrence rate of syncope of paced patients was compared with non-paced patients and with a subgroup of 18 propensity-score matched patients selected among non-paced patients. The 5-year Kaplan-Meier syncope free-rate was 81% (CI, 67%-90%) in the pacing group, 57% (47%-67%; p = 0.004) in the unmatched control group, 53% (27%-74%; p = 0.005) in the 18 propensity-matched patients. The hazard ratio of pacing versus non-pacing was 0.34 (CI, 0.18-0.70) when comparing with the whole non-pacing control group, and 0.25 (CI, 0.09-0.65) including only the propensity-score matched subgroup. No deaths were observed during the follow-up.Conclusions: In the selected VVS population with HUTT-induced cardioinhibitory response, pacemaker therapy with CLS function was associated to 66% relative and 24% absolute risk reduction of 5-year syncopal recurrence rate. Benefit was confirmed after controlling variables affecting propensity for pacemaker therapy. (c) 2018 Elsevier B.V. All rights reserved.

Heart failure is a leading cause of hospitalization and a significant medical burden in our society. Implantable medical devices are nowadays established therapies in heart failure patients that not only provide cardiac resynchronization therapy (CRT) and implantable cardioverter defibrillators (ICDs) therapy but are also able to continuously and remotely monitor diagnostic information of various physiologic parameters. The value of combining individual diagnostic variables to predict worsening of heart failure is still largely unclear but could eventually become a valuable tool towards a better heart failure management.SELENE HF (Selection of potential predictors of worsening Heart Failure) is an observational, multicentre study designed to prospectively collect follow-up and home monitoring data trends from a population of individuals with ICDs with or without resynchronization therapy (CRT-D), to document heart failure hospitalizations and deaths and to correlate these events with Home Monitoring data in order to identify the combination with the greatest sensitivity and specificity in predicting heart failure events.The purpose of this study is to describe the design of the study focusing on the Heart Failure Predicting model and statistical approach that will be used to analyse the data.The results of the SELENE HF study could help to select and define potential predictors of worsening heart failure in patients with remotely monitored ICD or CRT-D devices.ClinicalTrials.gov Identifier NCT01836510.

Ritme cardíac; Síncope reflex neurològic; Prova de la taula d’inclinació Ritmo cardíaco; Síncope reflejo neuromediado; Prueba de la mesa inclinada Cardiac pacing; Neuro-mediated reflex syncope; Tilt-Table test Background: The efficacy of dual-chamber cardiac pacing in neuro-mediated reflex syncope with a cardio-inhibitory response to the Tilt-Table test (TT) has not been definitively assessed so far. The lack of reproducibility of results from previous studies may be partially explained by discrepancies in subject selection and some weaknesses in design and methods. The European Society of Cardiology (ESC) has set a class IIb indication to pacemaker implantation in this population recommending further research. Methods/design: The BIOSync study is a multicenter, patient- and outcome-assessor-blind, randomized, parallel-arm, placebo-controlled trial with the objective of assessing the clinical benefit of cardiac pacing in patients with frequently recurrent reflex syncope, suspected (but not proven) to be triggered by asystolic pauses as showing a VASIS 2B response to the TT (>3-s pause regardless of blood pressure drop). The primary and secondary endpoints are time to first post-implantation recurrence of syncope or the combination of pre-syncope or syncope, respectively. One hundred and twenty-eight consenting patients will be 1:1 randomized to dual-chamber cardiac pacing 'on' or 'off' after pacemaker implantation, and followed up until the first adjudicated primary endpoint event for a maximum of 2 years. The so-called Closed Loop Stimulation function on top of dual-chamber pacing is the pacing mode selected in the study active arm. Participating patients are asked to self-report syncopal symptoms at least every 3 months with self-administered questionnaires addressed to an independent Adjudication Committee. Patients and members of the Adjudicating Committee are blinded to randomization. The study is designed to detect a 40% relative reduction in the 2-year incidence of syncopal recurrences with 80% statistical power. Discussion: The BIOSync study is designed to definitively assess the benefit of pacing against placebo in reflex syncope patients with a cardio-inhibitory response to the TT. The study will also provide important information on the efficiency of the TT in appropriately selecting reflex syncope patients for cardiac pacing. All study-related costs are being directly supported by the sponsor of the study (BIOTRONIK SE & Co. KG, Berlin, Germany). No further funding is provided.

Whereas cardiac pacing has a very limited role overall in patients with vasovagal syncope (VVS), there are three reasons which support pacing efficacy in tilt-induced asystolic VVS. These are: (1) contrary to mixed and vasodepressor forms, an asystolic tilt response is specific, i.e., diagnostic, of VVS and is unlikely to occur in control patients without history of syncope and in patients with cardiac syncope; (2) contrary to mixed and vasodepressor forms, an asystolic tilt response predicts a similar asystolic event during prolonged ECG monitoring with a positive predictive value of 86%; (3) the available evidence from trials supports the efficacy of dual-chamber pacing with a low recurrence rate of syncope after pacing ranging from 6% up to 23% during 3 years of follow-up. The latter results should be confirmed by an ongoing double-blind randomized controlled trial before cardiac pacing becomes an established indication. It is commonly believed that the most frequent cause of recurrence of syncope in patients treated with a pacemaker is an associated hypotensive reflex. In these cases additional measures should be used to counteract hypotension. Recognizing prodromal symptoms, avoiding triggers, and performing counterpressure maneuvers are the well-known first steps. There are two additional useful measures when these fail: stopping/reducing hypotensive drugs and (in selected cases) adding fludrocortisone.

Rate responsive pacemakers (PM) use different strategies to adapt the patient paced rate, with the aim of having the best hemodynamic performance in response to internal or external conditions. Closed-loop stimulation (CLS) uses intracardiac impedance as a sensor principle. The evaluation of impact of different pacing modalities and technologies on the blood pressure (BP) profiles is mainly investigated in short-term laboratory settings, mainly due to the need of reliable daily-based BP values. The impact of CLS pacing on systemic blood pressure (BP) has been studied on short term basis, but data on long term effects are scarse. This study present a telemedicine platform designed for evaluating the effect of the rate responsive technology on daily systolic and diastolic BP data. BP and pacemaker data were collected daily from fourteen patients during a 3 month period. The total number of monitoring days was 1277 (91 day/patient), for a total number of 4455 BP measures. On average 3.5 measure/day/patient were received). The analysis of the BP data showed that CLS pacing results in diastolic pressure closer to the normal values than accelerometer-based pacing, which were associated to lower diastolic pressures.

Remote Monitoring (RM) of cardiac implantable electronic devices (CIEDs) is recommended in management of Atrial Fibrillation (AF), which is a recognized risk factor for thromboembolism. We tried to elucidate whether stroke incidence observed in a large, remotely monitored population was consistent with the CHA2DS2VASc risk profile.Data from 1650 patients [76% male, age 72 (63-68), CHA2DS2VASc score 3.0 (2.0-4.0)] enrolled during the HomeGuide study and monitored with a daily-transmission RM system providing automatic alerts for AF, were analysed. Of those, 25% had a pacemaker and 75% an implantable cardioverter defibrillator with or without cardiac resynchronization. Estimations of the expected thromboembolic events were based on the population CHA2DS2VASc score profile used in a computer-simulated Markov model.Eight thromboembolic events were observed with a 4-year cumulative stroke rate of 0.8% (confidence interval, 0.4%-1.5%). Simulations returned from 18.7 to 17.1 expected events, depending on the AF duration assumed to trigger anticoagulation (one-sample log-rank p0.03). During the study period, 681 (84%) AF episodes and 129 (16%) atrial tachycardias were detected in 291 patients (18%): 93% of episodes were detected remotely in 269 patients, 66% of whom had no history of AF. Medical interventions were necessary in 305 episodes, 85% of which were detected remotely. Reaction time was 1 (0-6) days for remotely-detected episodes and 33 (14-121) days for episodes detected in clinic (p0.0001).In a large CIED population followed remotely for up to 4years, the incidence of thromboembolic events was less than half the estimations based on the CHA2DS2VASc risk profile.

Background: In patients without clinical indications for pacing the use of a single-lead implantable cardioverter defibrillator (ICD) implementing atrial sensing capability with proper signal amplification management may represent a useful therapeutic option, combining the positive features of both single and dual-chamber devices. The aim of the study was to evaluate the atrial signal amplification and its long-term stability in a single-lead ICD system adding atrial sensing to a standard single-chamber ICD. Methods: P-wave amplitudes were collected and compared at implant both with a conventional external device (“unfiltered” P wave) and telemetrically with the implanted ICD (“filtered” P wave). Filtered/unfiltered P-wave ratio (amplification factor, AmF) was evaluated at implant and during follow-up. Results: In 43 enrolled patients (38 men, age 64 ± 16 years), the mean filtered P wave at implant was significantly higher than the unfiltered P wave (3.85 ± 0.81 mV vs 2.0 ± 1.49 mV; P < 10−11), with a mean AmF value of 2.77 ± 1.62. In seven patients with atrial fibrillation at implant, the AmF was higher (4.62 ± 1.94) than in patients in sinus rhythm (2.41 ± 1.30; P < 0.001). A significant linear correlation was found between the inverse of P wave and the AmF (R = 0.82, P < 0.00001). In 25 patients followed for 384 ± 244 days, atrial undersensing was never documented and AmF did not change from implant (3.19 ± 1.82; P = 0.24), also in different body position and breathing conditions. Conclusions: The single-lead ICD system evaluated reliably amplified P-wave amplitudes by a factor of about three, maintaining this performance during the observed follow-up. (PACE 2012; 35:1119–1125)

Background: A relative high rate of clinical and device-related adverse events (AE) is generally reported in patients with implantable defibrillators for cardiac resynchronization therapy (CRT-D). Aim of this study was to compare a daily remote monitoring (RM) to a standard program of in-office visits. Methods and Results: We retrospectively analyzed RM database and hospital files of 99 CRT-D consecutive patients who were visited in the out-patient clinic every 3–4 months; thirty-three patients were in addition controlled remotely with RM (RM group). Kaplan-Meier curves of clinical or device-related AE-free rates were obtained. During a median follow-up of 7 months, clinical AEs were: ventricular and atrial arrhythmias in 14 and 11 patients, low CRT pacing in nine, heart failure, strokes, or death in 15. Device-related AEs were: insufficient pacing/sensing performances in nine patients, lead dislodgement in five. As comparing the RM group with the remaining patients, Kaplan-Meier curves of clinical AEs diverged to significantly different rates: 23.8% (confidence interval [CI] 0.1%–47.5%) in the RM group and 48.7% (21.6–75.7%) in the remaining patients (P = 0.00002), with a hazard ratio of 0.14 (CI 0.06–0.37). Nondivergent Kaplan-Meier curves were obtained for device-related AE-free rates. Conclusion: CRT-D patients followed with quarterly in-office visits without a daily RM system had an 86% higher risk of delayed detection of clinical AEs, during a median follow-up of 7 months. (PACE 2011; 34:208–216)

Introduction: Patients with pacemakers and implantable defibrillators (ICD) may experience asymptomatic atrial fibrillation (AF), detected with a delay depending on the in-person follow-up schedule. Home monitoring (HM) remote control with automatic alerts for AF may drive early anticoagulation, potentially reducing stroke risk. Methods and Results: A sample of 136 pacemaker (103) and ICD (33) patients with or without cardiac resynchronization therapy not taking anticoagulation at implant were monitored remotely with HM. Upon HM alerts for AF, patients were recalled to update therapy. Two-year data were entered in a computer Monte Carlo model, simulating 4,000 virtual subjects with the same AF and CHADS2 stroke risk distribution of our real population. Simulations reproduced a 2-year follow-up. Two thousand subjects were supposed to be followed with HM (HM group) and 2,000 with standard in-person follow-up (SF group) at 3, 6, 9, or 12 months. Two-year Kaplan-Meier cumulative probability of ≥24-hour AF was 15.6% (95%CI 8.5–23.3%); the AF-related symptom rate was 27% and the median CHADS2 score was 2. As a result of simulations, stroke incidence in case of AF was 2.3 ± 1.1% in the HM group and 2.4 ± 1.1%, 2.5 ± 1.2%, 2.7 ± 1.2%, and 2.9 ± 1.3% in the SF group with 3-, 6-, 9-, and 12-month follow-up programs, with odds ratios of 0.97 (95%CI 0.93–1.01), 0.91 (0.88–0.95), 0.87 (0.84–0.90), and 0.82 (0.79–0.85) (HM better if odds ratios

Aims Despite not being uncommon, limited evidence exists about predisposing factors for venous obstruction in patients with implantable electronic devices. We aimed to assess the prevalence of severe venous obstruction in patients with intravenous devices and identify predictor factors. Methods and results A total of 184 patients underwent venography to detect venous obstruction associated with the inserted lead. Vessel obstruction was graded as venous occlusion (complete flow interruption), severe obstruction (narrowing >90%), or mild–moderate obstruction (narrowing 50–90%). Severe venous obstruction/occlusion prevalence was 11.4% ( n = 21) and was always asymptomatic. Collateral circulation was found in 80.9% of patients with severe obstruction/occlusion. Twelve patients (6.5%) had 3 leads. The rates of patients with secondary prevention of sudden cardiac death as indication for implantable devices and of those of patients with 3 leads were significantly greater in the group with severe obstruction/occlusion than in the non-severe obstruction/occlusion group (respectively, P = 0.004 and P = 0.03). Logistic analysis adjusted for venous thromboembolic risk factors confirmed that secondary prevention of sudden cardiac death as indication for implantable devices [odds ratio (OR), 7.1; 95% confidence interval (CI): 1.4–35.3; P = 0.017] and the presence of 3 leads (OR, 8.5; 95% CI: 1.75–41.35; P = 0.008) were predictors of severe obstruction/occlusion. Conclusion In patients with implantable devices, severe venous obstruction prevalence is not negligible and the lack of symptoms does not exclude it. The presence of three leads and sudden cardiac death as indication for implantable devices seem to be associated with the presence of severe venous obstruction/occlusion.

MRI is a widely accepted diagnostic tool with unparalleled soft-tissue imaging capabilities. Most importantly, nowadays, MRI has been successfully used to evaluate myocardial structure, wall motion, perfusion and viability and it may, therefore, become a first-choice diagnostic technique for heart failure. Unfortunately, the presence of cardiac electronic devices (e.g., pacemakers and defibrillators) in patients is currently considered a contraindication for MRI, and consequently hinders access to MRI for a large portion of patients that could benefit from it. The Evia HF(-T) device (BIOTRONIK SE & Co. KG, Berlin, Germany) is the first pacemaker with the cardiac resynchronization therapy function for the treatment of ventricular dyssynchrony in heart failure patients that can be safely used in MRI (but not in cardiac magnetic resonance) under specific conditions. It completes the portfolio of magnetic resonance-conditional cardiac devices now available. The scope of this article is to describe the technic...

Aims Disorders such as paroxysmal atrial fibrillation (AF) and atrial tachyarrhythmias (AT) are difficult to investigate because of their intermittent, and sometimes asymptomatic, nature. The aim of this study was to investigate the daily temporal distribution of AT/AF episodes—onset and occurrence—by analysing data from 250 pacemaker-implanted, brady-tachy syndrome patients who have been enrolled in the Burden II Study. Methods and results Data were analysed accounting for the mode switch list which includes date, time, and duration of each mode switch episode. Chi-squared tests for goodness of fit were used to determine whether AT/AF episode were uniformly distributed. The population analysed in the present study suggests the occurrence of a circadian rhythm of paroxysmal AF episodes, similar to that described for other cardiovascular diseases, with clustering of events in the morning from 08:00 and (to a lesser degree) in the afternoon (03:00 to 18:00). The relative risk of AT/AF onset is 13% higher during daytime, 40% lower at night ( P < 0.000001). Conclusion The use of monitoring devices based on daily electrocardiogram (ECG) recording could be optimized with these data, thus increasing the probability to detect AT/AF episodes.