Association between implantable defibrillator-detected sleep apnea and atrial fibrillation: The DASAP-HF study.

INTRODUCTION: The Respiratory Disturbance Index (RDI) computed by an implantable cardioverter defibrillator (ICD) algorithm accurately identifies severe sleep apnea (SA). In the present analysis, we tested the hypothesis that RDI could also predict atrial fibrillation (AF) burden. METHODS: Patients with ejection fraction ≤35% implanted with an ICD were enrolled and followed up for 24 months. One month after implantation, patients underwent a polysomnographic study. The weekly mean RDI value was considered, as calculated during the entire follow-up period and over a 1-week period preceding the sleep study. The endpoints were as follows: daily AF burden of ≥5 min, ≥6 h, ≥23 h. RESULTS: Here, 164 patients had usable RDI values during the entire follow-up period. Severe SA (RDI ≥ 30 episodes/h) was diagnosed in 92 (56%) patients at the time of the sleep study. During follow-up, AF burden ≥ 5 min/day was documented in 70 (43%), ≥6 h/day in 48 (29%), and ≥23 h/day in 33 (20%) patients. Device-detected RDI ≥ 30 episodes/h at the time of the polygraphy, as well as the polygraphy-measured apnea hypopnea index ≥ 30 episodes/h, were not associated with the occurrence of the endpoints, using a Cox regression model. However, using a time-dependent model, continuously measured weekly mean RDI ≥ 30 episodes/h was independently associated with AF burden ≥ 5 min/day (hazard ratio [HR]: 2.13, 95% confidence interval [CI]: 1.24-3.65, p = .006), ≥6 h/day (HR: 2.75, 95% CI: 1.37-5.49, p = .004), and ≥23 h/day (HR: 2.26, 95% CI: 1.05-4.86, p = .037). CONCLUSIONS: In heart failure patients, ICD-diagnosed severe SA on follow-up data review identifies patients who are from two- to three-fold more likely to experience an AF episode, according to various thresholds of daily AF burden.

Clinical management of electrical storm: a current overview.

The number of patients affected by electrical storm has been continuously increasing in emergency departments. Patients are often affected by multiple comorbidities requiring multidisciplinary interventions to achieve a clinical stability. Careful reprogramming of cardiac devices, correction of electrolyte imbalance, knowledge of underlying heart disease and antiarrhythmic drugs in the acute phase play a crucial role. The aim of this review is to provide a comprehensive overview of pharmacological treatment, latest transcatheter ablation techniques and advanced management of patients with electrical storm.

Role of cardiac imaging in patients undergoing catheter ablation of ventricular tachycardia.

Ventricular tachycardia is a major health issue in patients with structural heart disease (SHD). Implantable cardioverter defibrillator (ICD) therapy has significantly reduced the risk of sudden cardiac death (SCD) in such patients, but on the other hand, it has led to frequent ICD shocks as an emerging problem, being associated with poor quality of life, frequent hospitalizations and increased mortality. Myocardial scar plays a central role in the genesis and maintenance of re-entrant arrhythmias, as the coexistence of surviving myocardial fibres within fibrotic tissue leads to the formation of slow conduction pathways and to a dispersion of activation and refractoriness that constitutes the milieu for ventricular tachycardia circuits. Catheter ablation has repeatedly proven to be well tolerated and highly effective in treating VT and in the last two decades has benefited from continuous efforts to determine ventricular tachycardia mechanisms by integration with a wide range of invasive and noninvasive imaging techniques such as intracardiac echocardiography, cardiac magnetic resonance, multidetector computed tomography and nuclear imaging. Cardiovascular imaging has become a fundamental aid in planning and guiding catheter ablation procedures by integrating structural and electrophysiological information, enabling the ventricular tachycardia arrhythmogenic substrate to be characterized and effective ablation targets to be identified with increasing precision, and allowing the development of new ablation strategies with improved outcomes. In this review, we provide an overview of the role of cardiac imaging in patients undergoing catheter ablation of ventricular tachycardia.

Are Atrial High-Rate Episodes Associated With Increased Risk of Ventricular Arrhythmias and Mortality?

OBJECTIVES: 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). BACKGROUND: Clinical relevance of AHREs in terms of VA rate and survival has not been outlined yet. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

Neuro-arrhythmology: a challenging field of action and research: a review from the Task Force of Neuro-arrhythmology of Italian Association of Arrhythmias and Cardiac Pacing.

: There is a growing interest in the study of the mechanisms of heart and brain interactions with the aim to improve the management of high-impact cardiac rhythm disorders, first of all atrial fibrillation. However, there are several topics to which the scientific interests of cardiologists and neurologists converge constituting the basis for enhancing the development of neuro-arrhythmology. This multidisciplinary field should cover a wide spectrum of diseases, even beyond the classical framework corresponding to stroke and atrial fibrillation and include the complex issues of seizures as well as loss of consciousness and syncope. The implications of a more focused interaction between neurologists and cardiologists in the field of neuro-arrhythmology should include in perspective the institution of research networks specifically devoted to investigate 'from bench to bedside' the complex pathophysiological links of the abovementioned diseases, with involvement of scientists in the field of biochemistry, genetics, molecular medicine, physiology, pathology and bioengineering. An investment in the field could have important implications in the perspectives of a more personalized approach to patients and diseases, in the context of 'precision'medicine. Large datasets and electronic medical records, with the approach typical of 'big data' could enhance the possibility of new findings with potentially important clinical implications. Finally, the interaction between neurologists and cardiologists involved in arrythmia management should have some organizational implications, with new models of healthcare delivery based on multidisciplinary assistance, similarly to that applied in the case of syncope units.

Nationwide survey on the current practice of ventricular tachycardia ablation.

METHODS: We performed a nationwide survey on the current practice of ventricular tachycardia catheter ablation in Italy during the year 2016. RESULTS: Among 145 operators participating in the survey, 58 (40.0%) did not perform any ventricular tachycardia ablation in 2016. Among those performing ventricular tachycardia ablation, 9 operators (6.2%) performed only right ventricular endocardial catheter ablation, 52 (35.9%) performed endocardial catheter ablation both in the right and left ventricle (LV) and 26 (17.9%) performed both endocardial and epicardial LV catheter ablations. Seventy operators (89.7%) among the 78 performing LV and epicardial ablations treated patients with ischemic cardiomyopathy; ablations in the setting of other causes were less frequently performed. The following were considered as minimum requirements for ventricular tachycardia ablation: presence of a three-dimensional mapping system (120 operators, 82.8%), ICU in the hospital (118 operators, 81.4%), operator's training in high volume centers (93 operators, 64.1%). Twenty-eight operators (19.3%) performed catheter ablation in patients with electrical storm only after hemodynamic stabilization, 41 operators (28.3%) also during the acute phase and 9 operators (6.2%) never performed catheter ablation in electrical storm patients; the remaining 67 operators did not perform ventricular tachycardia ablation at all, or performed ablations only in the right ventricle. CONCLUSION: The present survey provides a snapshot of the current invasive treatment of ventricular tachycardia by catheter ablation. The procedure, especially in the setting of ischemic cardiomyopathy, is performed nationwide. Complex cases, including those with electrical storm, should be managed within a preestablished integrated network of regional referral centers able to transfer patients as soon as possible.

Organizational model and reactions to alerts in remote monitoring of cardiac implantable electronic devices: A survey from the Home Monitoring Expert Alliance project.

BACKGROUND: This survey aimed to describe the organizational workflow of cardiac implantable electronic devices (CIEDs) remote monitoring (RM) service in ordinary practice. METHODS: A questionnaire was designed for our purpose and completed by 49 sites participating to the Italian Home Monitoring Expert Alliance. RESULTS: A dedicated organizational model for RM was set up for 86% of centers. The median RM team consisted of 2 (Interquartile range [IQR]: 1-3) physicians and 1 (IQR: 0-2) nurse. RM service was available in working hours and the median percentage of patients included was 100% (IQR: 10%-100%) for implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy (CRT) recipients and 5% (IQR:0%-30%) for pacemakers. In-office follow-up was performed every 12 and 6 months for pacemaker and ICD/CRT recipients, respectively. More than 90% of sites used to activate all technical alerts, with a prompt reaction in case of an out-of-range parameter. The threshold for atrial fibrillation (AF) daily burden notification in most cases ranged from 2.4 to 7.2 hours. All ventricular arrhythmias alerts were usually switched on: an inappropriate therapy or more than one appropriate episode triggered an urgent in-hospital visit. Concerning heart failure, low CRT percentage pacing alert was always used, while the other available notifications were less frequently switched on. CONCLUSIONS: This survey showed that RM service was usually set up with a primary nursing model including on average two responsible physicians and one nurse and mainly offered to ICD/CRT patients. Technical, AF and ventricular arrhythmia alerts triggered prompt reactions, while heart failure related indexes were generally less applied.

Clinically oriented device programming in bradycardia patients: part 1 (sinus node disease). Proposals from AIAC (Italian Association of Arrhythmology and Cardiac Pacing).

: Modern pacemakers have an increasing number of programable parameters and specific algorithms designed to optimize pacing therapy in relation to the individual characteristics of patients. When choosing the most appropriate pacemaker type and programing, the following variables must be taken into account: the type of bradyarrhythmia at the time of pacemaker implantation; the cardiac chamber requiring pacing, and the percentage of pacing actually needed to correct the rhythm disorder; the possible association of multiple rhythm disturbances and conduction diseases; the evolution of conduction disorders during follow-up. The goals of device programing are to preserve or restore the heart rate response to metabolic and hemodynamic demands; to maintain physiological conduction; to maximize device longevity; to detect, prevent, and treat atrial arrhythmia. In patients with sinus node disease, the optimal pacing mode is DDDR. Based on all the available evidence, in this setting, we consider appropriate the activation of the following algorithms: rate responsive function in patients with chronotropic incompetence; algorithms to maximize intrinsic atrioventricular conduction in the absence of atrioventricular blocks; mode-switch algorithms; algorithms for autoadaptive management of the atrial pacing output; algorithms for the prevention and treatment of atrial tachyarrhythmias in the subgroup of patients with atrial tachyarrhythmias/atrial fibrillation. The purpose of this two-part consensus document is to provide specific suggestions (based on an extensive literature review) on appropriate pacemaker setting in relation to patients' clinical features.

Clinically oriented device programming in bradycardia patients: part 2 (atrioventricular blocks and neurally mediated syncope). Proposals from AIAC (Italian Association of Arrhythmology and Cardiac Pacing).

: The purpose of this two-part consensus document is to provide specific suggestions (based on an extensive literature review) on appropriate pacemaker setting in relation to patients' clinical features. In part 2, criteria for pacemaker choice and programming in atrioventricular blocks and neurally mediate syncope are proposed. The atrioventricular blocks can be paroxysmal or persistent, isolated or associated with sinus node disease. Neurally mediated syncope can be related to carotid sinus syndrome or cardioinhibitory vasovagal syncope. In sinus rhythm, with persistent atrioventricular block, we considered appropriate the activation of mode-switch algorithms, and algorithms for auto-adaptive management of the ventricular pacing output. If the atrioventricular block is paroxysmal, in addition to algorithms mentioned above, algorithms to maximize intrinsic atrioventricular conduction should be activated. When sinus node disease is associated with atrioventricular block, the activation of rate-responsive function in patients with chronotropic incompetence is appropriate. In permanent atrial fibrillation with atrioventricular block, algorithms for auto-adaptive management of the ventricular pacing output should be activated. If the atrioventricular block is persistent, the activation of rate-responsive function is appropriate. In carotid sinus syndrome, adequate rate hysteresis should be programmed. In vasovagal syncope, specialized sensing and pacing algorithms designed for reflex syncope prevention should be activated.

Does the CHA2DS2-VASc score reliably predict atrial arrhythmias? Analysis of a nationwide database of remote monitoring data transmitted daily from cardiac implantable electronic devices.

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 <.001) with AHRE burden ≥15 minutes to 1.26 (confidence interval 1.11-1.42; P <.001) with AHRE burden ≥7 days. At receiver operating curve analysis, CHA2DS2-VASc ≥2 was estimated to predict persistent forms of AHREs with 95.8% sensitivity but 11.7% specificity at 3 years. CHA2DS2-VASc ≥5 had 77.0% specificity but 34.6% sensitivity. CONCLUSION: In a CIED population with no previous diagnosis of clinical AF, AHRE incidence increased with increasing CHA2DS2-VASc score. The association was stronger with longer AHREs, but the accuracy of CHA2DS2-VASc as AHRE predictor was moderate.

Diagnostic power and healthcare resource consumption of a dedicated workflow algorithm designed to manage thoracic impedance alerts in heart failure patients by remote monitoring.

PURPOSE: Modern cardiac implantable devices provide diagnostic information on several physiological variables which are associated with worsening heart failure, creating an opportunity for early intervention to prevent heart failure symptoms and hospitalizations. We evaluated diagnostic accuracy and workload of a remote monitoring (RM) workflow algorithm which leverages intrathoracic impedance and other device diagnostics. METHODS: In our RM workflow a team of expert nurses was responsible for continuity of care, direct relationship with patients and implementation of a specific protocol to evaluate RM alerts and to limit unnecessary resource consumption. Each patient was univocally assigned to a reference nurse. End points were diagnostic accuracy, healthcare utilization, defined as any hospital admission, and actionability of alerts, defined as medication change or other clinical action. RESULTS: One-hundred twenty-six consecutive patients with implantable cardioverter defibrillator/cardiac resynchronization therapy defibrillator were followed for a median time of 23 months. Out of 2176 remote transmissions, 893 (41%) in 111 patients (88.1%) showed clinically relevant events triggered by 574 alerts [2.2 (95% confidence interval = 2.0-2.4) per patient per year]. Among 309 alerts with intrathoracic impedance crossing, heart failure deterioration was confirmed in 116 (37.5%). Clinical actions followed 76/116 (65.5%) true heart failure alerts and 17/193 (8.8%) false-positive alerts (P < 0.001). In particular, drug therapy change followed 72/116 (62.1%) true heart failure alerts and 15/193 (7.8%) false-positive alerts (P < 0.001). Healthcare utilization occurred in 65.5% true heart failure alerts and in 24.9% false-positive alerts (P < 0.001). CONCLUSION: A dedicated workflow algorithm results in more focused clinical surveillance leading to prompt detection and treatment of acute heart failure events without wasting healthcare resource.

Prognostic implications of mitral regurgitation in patients after cardiac resynchronization therapy.

AIM: Mitral regurgitation (MR) is a common finding in patients with heart failure with debatable effects on prognosis. Reduction in MR is one of the mechanisms by which cardiac resynchronization therapy (CRT) exerts its beneficial effects. We investigated the prognostic impact of baseline MR and MR persistence after CRT on outcomes of treated patients. METHODS AND RESULTS: We prospectively followed 1122 CRT patients (66.4 ± 10.3 years, 78% male) who were stratified according to baseline MR severity as having MR- (degree 0-1; n = 508, 45%) or MR+ (degrees 2-3-4; n = 614, 55%). In 916 patients (82%) with MR severity data available at 1-year follow-up, the annual mortality rate was 3.4 and 6.0 per patient-year in the MR- and MR+ group, respectively, with a 1-year incidence rate ratio (IRR) of 1.76 (P < 0.001). Similar results were observed for cardiovascular mortality (1-year IRR 1.72, P = 0.002). When considering survival according to MR severity after CRT, all-cause and cardiovascular mortality were lower in the improved than in the worsened group (1-year IRR 1.87 and 2.33, respectively; both P < 0.001). Regression analysis showed that absence of MR improvement at follow-up was a significant independent predictor of both all-cause and cardiovascular mortality. CONCLUSIONS: Baseline significant MR and absence of MR improvement after CRT are strongly predictive of less favourable long-term survival.

Association between ventricular pacing and persistent atrial fibrillation in patients indicated to elective pacemaker replacement: Results of the Prefer for Elective Replacement MVP (PreFER MVP) randomized study.

BACKGROUND: Pacing in the right ventricle can cause a variety of detrimental effects, including atrial tachyarrhythmias (atrial tachycardia [AT]/atrial fibrillation [AF]). OBJECTIVE: The purpose of this study was to evaluate the incidence and predictors of persistent AT/AF in patients with long-term exposure to ventricular pacing. METHODS: In a multicenter international trial, 605 patients (age 75 ± 11 years, 240 women) referred for replacement of an implanted pacemaker or implantable cardioverter-defibrillator (ICD), with a history of high-percentage (>40%) ventricular pacing, were randomly allocated to standard dual-chamber pacing or managed ventricular pacing (MVP), a pacing modality that minimizes ventricular pacing. The main end-point of this secondary analysis of the PreFER MVP randomized study was persistent AT/AF, defined as ≥7 consecutive days with AT/AF or AT/AF interrupted by atrial cardioversion or AT/AF present during 2 consecutive follow-up visits. RESULTS: Persistent AT/AF was observed in 71 patients (11.7%) after 2 years of follow-up. At multivariable Cox regression analysis, prior AT/AF (hazard ratio [HR] 2.85, 95% confidence interval [CI] 1.20-6.22, P = .017) and ventricular pacing percentage, estimated in the first 3 months, ≥10% (HR 3.24, 95% 95% CI 1.13-9.31, P = .029) were independent predictors for persistent AT/AF. MVP was associated with persistent AT/AF risk (HR 3.41, 95% 95% CI 1.10-10.6, P = .024) in the subgroup of patients with baseline long PR interval (PR >230 ms) but not in the whole population. CONCLUSION: In pacemaker and ICD replacement patients, a high percentage of ventricular pacing is associated with higher risk of persistent AT/AF. Use of algorithms that minimize right ventricular pacing may benefit patients with normal spontaneous AV conduction but should be evaluated with caution in patients with long PR interval.

Managed ventricular pacing compared with conventional dual-chamber pacing for elective replacement in chronically paced patients: results of the Prefer for Elective Replacement Managed Ventricular Pacing randomized study.

BACKGROUND: Several studies have shown that unnecessary right ventricular pacing has detrimental effects. OBJECTIVE: To evaluate whether minimization of ventricular pacing as compared with standard dual-chamber pacing (DDD) improves clinical outcomes in patients referred for pacemaker or implantable cardioverter-defibrillator (ICD) replacement. METHODS: In an international single-blind, multicenter, randomized controlled trial, we compared DDD with managed ventricular pacing (MVP), a pacing mode developed to minimize ventricular pacing by promoting intrinsic atrioventricular conduction. We included patients referred for device replacement with >40% ventricular pacing, no cardiac resynchronization therapy upgrade indication, no permanent atrial fibrillation (AF), and no permanent complete atrioventricular block. Follow-up was for 2 years. The primary end point was cardiovascular hospitalization. The intention-to-treat analysis was performed by using Kaplan-Meier method and the log-rank test. RESULTS: We randomized 605 patients (556 referred for pacemaker and 49 referred for ICD replacement; mean age 75 ± 11 years; 365 [60%] men, at 7.7 ± 3.3 years from first device implantation) to MVP (n = 299) or DDD (n = 306). We found no significant differences in the primary end point cardiovascular hospitalization (MVP: 16.3% vs DDD: 14.5%; P = .72) and the secondary end point persistent AF (MVP: 15.4% vs DDD: 11.2%; P = .08), permanent AF (MVP: 4.1% vs DDD: 3.1%; P = .44), and composite of death and cardiovascular hospitalization (MVP: 23.9% vs DDD: 20.2%; P = .48). MVP reduced right ventricular pacing (median 5% vs 86%; Wilcoxon, P < .0001) as compared with DDD. CONCLUSIONS: In patients referred for pacemaker and ICD replacement with clinically well-tolerated long-term exposure to >40% ventricular pacing in the ventricle, a strategy to minimize ventricular pacing is not superior to standard DDD in reducing incidence of cardiovascular hospitalizations.

Impact of in-clinic follow-up visits in patients with implantable cardioverter defibrillators: demographic and socioeconomic analysis of the TARIFF study population.

PURPOSE: Remote monitoring of cardiac implantable electronic devices has been demonstrated to safely reduce frequency of hospital visits. Limited studies are available evaluating the economic impact. The aim of this article is to highlight the social impact and costs for the patients associated with hospital visits for routine device follow-up at the enrollment visit for the TARIFF study (NCT01075516). METHODS: TARIFF is a prospective, cohort, observational study designed to compare the costs and impact on quality of life between clinic-based and remote care device follow-up strategies. RESULTS: Two hundred nine patients (85.2 % males) were enrolled in the study; 153 patients (73.2 %) were retired, 36 (17.2 %) were active workers, 18 (8.6 %) were housewives, and 2 (1.0 %) were looking for a job. Among active workers, 63.9 % required time off from work to attend the hospital visit, while 67.0 % of all patients had to interrupt daily activities. The majority of patients spent half a day or more attending the visit. A carer accompanied 77 % of patients. Among carers, 36.6 % required time off from work, and 77.6 % had to interrupt daily activities. Median distance traveled was 36 km. The average cost of travel was 10 euros with 25 % of patients spending more than 30 euros. CONCLUSIONS: Data from patients enrolled in the TARIFF registry confirm that there are social and economic impacts to patients attending routine device checks in hospital which can be significantly reduced by using a remote monitoring strategy.

Rationale and design of the health economics evaluation registry for remote follow-up: TARIFF.

AIMS: The aims of the study are to develop a cost-minimization analysis from the hospital perspective and a cost-effectiveness analysis from the third payer standpoint, based on direct estimates of costs and QOL associated with remote follow-ups, using Merlin@home and Merlin.net, compared with standard ambulatory follow-ups, in the management of ICD and CRT-D recipients. METHODS AND RESULTS: Remote monitoring systems can replace ambulatory follow-ups, sparing human and economic resources, and increasing patient safety. TARIFF is a prospective, controlled, observational study aimed at measuring the direct and indirect costs and quality of life (QOL) of all participants by a 1-year economic evaluation. A detailed set of hospitalized and ambulatory healthcare costs and losses of productivity that could be directly influenced by the different means of follow-ups will be collected. The study consists of two phases, each including 100 patients, to measure the economic resources consumed during the first phase, associated with standard ambulatory follow-ups, vs. the second phase, associated with remote follow-ups. CONCLUSION: Remote monitoring systems enable caregivers to better ensure patient safety and the healthcare to limit costs. TARIFF will allow defining the economic value of remote ICD follow-ups for Italian hospitals, third payers, and patients. The TARIFF study, based on a cost-minimization analysis, directly comparing remote follow-up with standard ambulatory visits, will validate the cost effectiveness of the Merlin.net technology, and define a proper reimbursement schedule applicable for the Italian healthcare system. TRIAL REGISTRATION: NCT01075516.

Long-term complications related to biventricular defibrillator implantation: rate of surgical revisions and impact on survival: insights from the Italian Clinical Service Database.

BACKGROUND: Long-term data on device-related untoward events in patients receiving defibrillators for resynchronization therapy (CRT-D) are lacking. We quantified the frequency of repeat invasive procedures and the nature of long-term complications in current clinical practice and examined possible predictors of device-related events and their association with long-term patient outcome. METHODS AND RESULTS: We analyzed data from 3253 patients who underwent de novo successful implantation of CRT-D and were followed up for a median of 18 months (25th to 75th percentiles: 9 to 30) in 117 Italian centers. Device-related events were reported in 416 patients, and, specifically, surgical interventions for system revision were described in 390 patients. Four years after the implantation procedure, 50% of patients underwent surgical revision for battery depletion and 14% for unanticipated events. For comparison, at 4 years battery depletion occurred in 10% and 13% of patients who received single- and dual-chamber defibrillators at the study centers, and unanticipated events were reported as 4% and 9%, respectively. In CRT-D, infections occurred at a rate of 1.0%/y, and the risk of infections increased after device replacement procedures (hazard ratio, 2.04; 95% confidence interval, 1.01 to 4.09; P=0.045). Left ventricular lead dislodgements were reported at a rate of 2.3%/y and were predicted by longer fluoroscopy time and higher pacing threshold on implantation. Device-related events were not associated with a worse clinical outcome; indeed, the risk of death was similar in patients with and without surgical revision (hazard ratio, 0.90; 95% confidence interval, 0.56 to 1.47; P=0.682). CONCLUSIONS: In current clinical practice device-related events are more frequent in CRT-D than in single- or dual-chamber defibrillators, and are frequently managed by surgical intervention for system revision. However, a worse clinical outcome is not associated with these events. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01007474.

Atrial tachyarrhythmias and cardiac resynchronisation therapy: clinical and therapeutic implications.

Atrial fibrillation (AF) represents one of the most important comorbidities in patients with heart failure (HF). This report highlights the available evidence for the relationship between AF and cardiac resynchronisation therapy (CRT). Studies on the use of CRT in patients with HF and AF have demonstrated its effectiveness. It seems to reduce the AF burden and determines left atrial reverse remodelling. No definite data are available on AF ablation in patients with CRT but it might represent a therapeutic option. Furthermore, modern implantable pacemakers and cardioverter-defibrillators are provided with diagnostic algorithms which allow a better understanding of the AF burden.

Home monitoring in patients with implantable cardiac devices: is there a potential reduction of stroke risk? Results from a computer model tested through monte carlo simulations.

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 CHADS(2) 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 CHADS(2) 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 <1), respectively. CONCLUSIONS: Daily HM potentially reduces the stroke risk by 9% to 18% with respect to SF with intervisit intervals of 6 to 12 months.

Primary prevention implantation of cardioverter defibrillator without defibrillation threshold testing: 2-year follow-up.

BACKGROUND: Even though the intraoperative threshold testing of the implantable cardioverter defibrillator (ICD) may cause hemodynamic impairment or be unfeasible, it is still considered required standard practice at the time of implantation. We compared the outcome of ICD recipients who underwent defibrillation threshold testing (DFT) with that of patients in whom no testing was performed. METHODS: A total of 291 subjects with ischemic dilated cardiomyopathy received transvenous ICDs between January 2000 and December 2004 in five Italian cardiology centers. In two centers, DFT was routinely performed in 137 patients (81% men; mean age 69+/-9 years; mean ejection fraction 26+/-4%) (DFT group), while three centers never performed DFT in 154 patients (90% men; mean age 69+/-9 years; mean ejection fraction 27+/-5%) (no-DFT group). RESULTS: We compared total mortality, total cardiovascular mortality, sudden cardiac death (SCD), and spontaneous episodes of ventricular arrhythmia (sustained ventricular tachycardia, VT, and ventricular fibrillation, VF) between these groups 2 years after implantation (median 23 months, 25th-75th percentile, 12-44 months). On comparing the DFT and no-DFT groups, we found an overall mortality rate of 20% versus 16%, cardiovascular mortality of 13% versus 10%, SCD of 3% versus 0.6%, VT incidence of 8% versus 10%, and VF incidence of 6% versus 4% (no significant difference in any comparison). CONCLUSIONS: No significant differences in the incidence of clinical outcomes considered emerged between no-DFT and DFT groups. These results should be confirmed in larger prospective studies.