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Background: Substernal lead placement of the extravascular implantable cardioverter-defibrillator (EV ICD) permits both defibrillation at thresholds similar to those seen with transvenous ICDs and effective antitachycardia pacing (ATP), while avoiding the vasculature and associated complications. The global Pivotal study has shown the EV ICD system to be safe and effective through 6 months, but long-term experience has yet to be published. We aim to report the performance and safety of the EV ICD system throughout the study., Methods: The EV ICD Pivotal study was a prospective, global, single-arm, pre-market clinical study. Individuals with a class I or IIa indication for a single-chamber ICD per guidelines were enrolled. Freedom from major system- or procedure-related complications, as well as appropriate and inappropriate therapy rates, were assessed through 3 years using the Kaplan-Meier method. Anti-tachycardia pacing success was calculated using simple proportions., Results: An implant was attempted in 316 patients [25.3% female, 53.8±13.1 years old, 81.6% primary prevention, LVEF 38.9%±15.4%]. Of 299 patients with a successful implant, 24 experienced 82 spontaneous arrhythmic episodes that were appropriately treated with either ATP only (38, 46.3%), shock only (34, 41.5%), or both (10, 12.2%) for a Kaplan-Meier-estimated rate of first any appropriate therapy of 9.2% at 3 years. Antitachycardia pacing was successful in 77.1% (37/48) of episodes, and ATP usage significantly increased from discharge to last follow-up visit (P<0.0001). Shock therapy was successful in 100% (27/27) of discrete, spontaneous ventricular arrhythmias. The inappropriate shock rates at 1 and 3 years were 9.8% and 17.5%, respectively, with P-wave oversensing the predominant cause. No major intraprocedural complications were reported and the estimated freedom from system- or procedure-related major complications was 91.9% at 1 year and 89.0% at 3 years. The most common major complications were lead dislodgement (10 events; n=9 patients, 2.8%), postoperative wound or device pocket infection (n=8, 2.5%), and device inappropriate shock delivery (n=4, 1.3%). Twenty-four system revisions were performed as a result of major complications related to the EV ICD system or procedure., Conclusions: From implant to study completion, the EV ICD Pivotal study demonstrated that a single integrated system with an extravascular lead placed in the substernal space maintains high ATP success, effective defibrillation, and a consistent safety profile.

Aims: Brugada syndrome (BrS) is an inherited arrhythmic disease characterized by a coved ST-segment elevation in the right precordial electrocardiogram leads (type 1 ECG pattern) and is associated with a risk of malignant ventricular arrhythmias and sudden cardiac death. In order to assess the predictive value of the Shanghai Score System for the presence of a SCN5A mutation in clinical practice, we studied a cohort of 125 patients with spontaneous or fever/drug-induced BrS type 1 ECG pattern, variably associated with symptoms and a positive family history., Methods: The Shanghai Score System items were collected for each patient and PR and QRS complex intervals were measured. Patients were genotyped through a next-generation sequencing (NGS) custom panel for the presence of SCN5A mutations and the common SCN5A polymorphism (H558R)., Results: The total Shanghai Score was higher in SCN5A+ patients than in SCN5A- patients. The 81% of SCN5A+ patients and the 100% of patients with a SCN5A truncating variant exhibit a spontaneous type 1 ECG pattern. A significant increase in PR (P = 0.006) and QRS (P = 0.02) was detected in the SCN5A+ group. The presence of the common H558R polymorphism did not significantly correlate with any of the items of the Shanghai Score, nor with the total score of the system., Conclusion: Data from our study suggest the usefulness of Shanghai Score collection in clinical practice in order to maximize genetic test appropriateness. Our data further highlight SCN5A mutations as a cause of conduction impairment in BrS patients., (Copyright © 2023 Italian Federation of Cardiology - I.F.C. All rights reserved.)

Background: The noninferiority of left ventricular pacing alone (LVp) compared with biventricular pacing (BIV) has not been yet definitely documented. In this study, we reviewed all the original echocardiographic measures of the Biventricular versus Left Univentricular Pacing with ICD Back-up in Heart Failure Patients (B-LEFT HF) trial in order to investigate mechanisms underlying LV remodelling with both pacing modalities., Methods: Patients with New York Heart Association functional class (NYHA) III or IV despite optimal medical therapy, LVEF 35% or less, left ventricular end-diastolic diameter (LVEDD) more than 55 mm, QRS duration at least 130 ms were randomized to BIV or LVp for 6 months. The primary end point was a composite of at least 1 point decrease in NYHA class and at least 5 mm decrease in left ventricular end-systolic diameter (LVESD). An additional end point was a LVp reverse remodelling defined as at least 10% decrease in LVESD. Mitral regurgitation and all echocardiographic measures were reassessed after 6-month follow-up., Results: One hundred and forty-three patients were enrolled. Seventy-six patients were in the BIV and 67 were in the LVp group. Left ventricular volumes decreased significantly without difference between groups (P = 0.8447). Similarly, left ventricular diameters decreased significantly in both groups with a significant decrease in LVESD with BIV (P < 0.0001), but not with LVp (P = 0.1383). LVEF improved in both groups without difference (P = 0.8072). Mitral regurgitation did not improve either with BIV, or with LVp., Conclusion: The echocardiographic sub-analysis of B-LEFT study showed the substantial equivalence of LVp in favouring left ventricular reverse remodelling as compared with BIV., (Copyright © 2023 Italian Federation of Cardiology - I.F.C. All rights reserved.)

Background: Despite the common use of biphasic electrical cardioversion (ECV) to convert atrial fibrillation (AF), we lack definite recommendations on electrode configuration., Methods: We adopted a quasi-experimental design enrolling all candidates to ECV for AF. In the first stage, two units were involved, one using antero-apical pads (AAP) and the second antero-posterior adhesive patches (APP). These data enabled the creation of a decision algorithm to personalize the ECV approach, which was subsequently validated during the second stage., Results: A total of 492 patients were enrolled overall. In the first stage, APP and AAP presented similar conversion rates (87.4 vs. 86.9% at first attempt of a step-up protocol, P = 0.661). While body surface area (BSA) ≤2.12 m2 was an independent predictor in the overall population, the two components (height and weight) acted differently in the two configurations: being height ≤1.73 m2 a significant cut-off value in the AAP subgroup, and weight <83 kg in the APP subgroup. Considering these cut-offs, we developed a decision algorithm for electrode configuration. In the second stage, algorithm validation confirmed an improvement in the first shock efficacy with respect to the results of the first stage (93.2 vs. 87.2%, P = 0.025), with a significant reduction in shock impedance (70.8 ± 15.3 vs. 81.8 ± 15.6, P < 0.001)., Conclusion: Patients with high BSA require high energy shocks for sinus rhythm restoration with ECV. Weight seems to affect more APP configuration, while height seems to impact more for the AAP. These findings have the potential to optimize ECV in clinical practice., (Copyright © 2022 Italian Federation of Cardiology - I.F.C. All rights reserved.)

Aims: Cardiac resynchronization therapy (CRT) is indicated in patients with systolic heart failure (HF), severe left ventricle (LV) dysfunction and interventricular dyssynchrony.In prospective observational research, we aimed to evaluate whether CRT-induced LV reverse remodelling and occurrence of ventricular arrhythmias (VT/VF) independently contribute to prognosis in patients with CRT defibrillators (CRT-D)., Methods: In 95 Italian cardiological centres, after a screening period of 6 months, patients were categorized according to VT/VF occurrence and CRT response, defined as LV end-systolic volume relative reduction >15% or LV ejection fraction absolute increase >5%. The main endpoint was death or HF hospitalizations., Results: Among 1308 CRT-D patients (80% male, mean age 66 years), at 6 months, follow-up 71% were identified as CRT responders and 12% experienced appropriate VT/VF detections. The main endpoint was significantly and independently associated with previous myocardial infarction, New York Heart Association Class, VT/VF occurrence and with CRT response. CRT nonresponder patients who suffered VT/VF in the screening period had a risk of death or HF hospitalizations [HR = 7.82, 95% confidence interval (CI) = 3.95-15.48] significantly (P < 0.001) higher than CRT responders without VT/VF occurrence. This risk is mitigated without VT/VF occurrence (HR = 3.47, 95% CI = 2.03-5.91, P < 0.001) or in case of CRT response (HR = 3.11, 95% CI = 1.44-6.72, P = 0.004)., Conclusion: Our data show that both CRT response and occurrence of VT/VF independently contribute to the risk of death or HF-related hospitalizations in CRT-D patients. Early VT/VF occurrence may be identified as a marker of disease severity than can be mitigated by CRT response both in terms of all-cause mortality and long-term VT/VF onset., Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00147290 and NCT00617175., (Copyright © 2021 Italian Federation of Cardiology - I.F.C. All rights reserved.)

Peripheral extracorporeal membrane oxygenation (ECMO) setting remains a valid option to treat cardiogenic shock (CS). We investigated a percutaneous approach to unload the left ventricle (LV) while on veno-arterial (v-a) peripheral ECMO support. Between 2017 and 2018, eight patients (three females, mean age: 49.6 years old, and five males, mean age: 58 years old, respectively) suffered refractory CS due to acute myocardial infarction (n = 4), acute myocarditis (n = 2), acute decompensation on chronic heart failure (n = 1), and primary graft failure after heart transplantation (Htx) (n = 1), respectively. After a multidisciplinary CS team discussion, it was decided to proceed with peripheral v-a ECMO placement and percutaneous LV venting via right internal jugular vein access to drain the pulmonary artery (PA), in the hybrid operating room. In a single postcardiotomy case, the PA trunk was vented centrally. Mean ECMO support time was 8.5 days. Seven (87.5%) patients were successfully weaned from ECMO and one (12.5%) successfully bridged to Htx. All patients were successfully discharged after treatment except for a single case who died due to sepsis. In case of not recommended usage of LV apical venting, the adoption of v-a peripheral ECMO support associated with percutaneous PA drainage enables the rapid onset of extracorporeal life support with an effective biventricular unloading.

Aims: About one-third of patients receiving cardiac resynchronization therapy (CRT) are not responders, due to either patient selection or technical issues. Left ventricular quadripolar passive fixation leads (QPL) and bipolar active fixation (BAF) leads have been designed to ensure a targeted left ventricular stimulation area, minimizing lead dislodgments and phrenic nerve stimulation (PNS). The aim was to compare real-world safety and efficacy of BAF (Attain Stability, Medtronic Plc.) and QPL (Attain Performa, Medtronic Plc.)., Methods: We performed a retrospective analysis examining procedural and follow-up data of 261 BAF and 124 QPL (programmed to single-site left ventricular pacing), included in the ClinicalService project from 16 Italian hospitals., Results: At median follow-up of 12 months, no difference in left ventricular pacing threshold was recorded between BAF and QPL (1.3 ± 0.9 V @0.4 ms vs. 1.3 ± 1.0 V @0.4 ms; P = 0.749). Total left ventricular lead dislodgement rate was 1.43/100 patient-years in BAF vs. 2.9/100 patient-years in QPL (P = 0.583). However, no dislodgements occurred among BAF after hospital discharge. Events requiring repeated surgery or permanently turning CRT off occurred in 0.8% of BAF, as compared with 4.0% of QPL (P = 0.025). There was no difference between groups in the echo CRT responders' rate (70% of BAF and 66% of QPL; P = 0.589) or in the annual rate of heart failure hospitalization (P = 0.513)., Conclusions: BAF resulted in noninferior clinical outcome and CRT responders' rate in comparison to QPL. Moreover, BAF ensured more precise and stable placement in cardiac veins, with comparable electrical performance and less than 1% patients with unsolved PNS.

Aims: To perform an updated meta-analysis to assess efficacy, safety and technical performance of pulmonary vein isolation using cryoballoon or radiofrequency catheter ablation in patients with paroxysmal or persistent atrial fibrillation., Methods: In June 2017, databases and websites were systematically searched for systematic reviews, randomized controlled trials and observational studies reporting data on efficacy, safety and technical performance outcomes at follow-up at least 12 months. Researchers independently assessed records' eligibility, inclusion and methodological quality of included studies., Results: Six randomized controlled trials and 25 observational studies - 11 853 patients were included. Studies on paroxysmal atrial fibrillation were 29 and included 11 635 patients. Meta-analysis results showed no difference between cryoballoon and radiofrequency in terms of recurrent atrial fibrillation [risk ratio 1.04, 95% confidence interval (CI) 0.98-1.10] or atrial tachyarrhythmias (risk ratio 1.04, 95% CI 1-1.08) and fluoroscopy time (mean difference -1.92 min, 95% CI -4.89 to 1.05). Cryoballoon ablation was associated with fewer reablations (risk ratio 0.79, 95% CI 0.64-0.98), lower incidence of pericardial effusion (risk ratio 0.52, 95% CI 0.31-0.89) and cardiac tamponade (risk ratio 0.33, 95% CI 0.18-0.62) and shorter total procedural time (mean difference -23.48 min, 95% CI -37.97; -9.02) but with higher incidence of phrenic nerve palsy (risk ratio 5.43, 95% CI 2.67-11.04). Prespecified subgroup analysis confirmed overall results as for freedom from atrial fibrillation and atrial tachyarrhythmias. Only two observational studies included patients with persistent atrial fibrillation, thus hindering any conclusion in this population., Conclusion: In patients with paroxysmal atrial fibrillation, cryoballoon and radiofrequency ablation produce similar results in terms of freedom from recurrent atrial fibrillation or atrial tachyarrhythmias but with a different safety profile, being cryoballoon ablation less associated with cardiac complications but more likely to cause phrenic nerve palsy.

Aims: Knowledge of the long-term progression of rhythm disorders requiring pacemaker implantation could have significant implications for the choice of device and its management during follow-up. Accordingly, we conducted an observational study to analyse the long-term progression of rhythm disorders requiring pacemaker implantation., Methods: This multicentre, observational study enrolled 1810 pacemaker patients (age 71.6 ± 13.3 years, men 53.8%) consecutively evaluated during scheduled pacemaker follow-up visits. To evaluate the long-term progression of rhythm disorders, we analysed the patient's rhythm disorders at the time of device implantation and during follow-up. After pacemaker implantation, the rhythm disorders were reassessed and recorded at each scheduled pacemaker follow-up visit, and the spontaneous rhythm was analysed during pacemaker interrogation., Results: During a median follow-up of 61.6 months, we observed a progression of the primary rhythm disorder in 295 patients (16.3%; worsening of the preexisting rhythm disorder in 7.7%; occurrence of a new rhythm disorder added to the preexisting one in 8.6%). Specifically, the cumulative per-year risks of developing the following disorders were: atrioventricular block (AVB) in patients implanted for sinus node disease (SND), 0.3%; permanent atrial fibrillation in SND patients, 2.9%; SND in AVB patients, 0.7%; and persistent AVB in patients implanted for chronic bifascicular block 3.0%., Conclusion: Our results revealed that rhythm disorders requiring pacemaker implantation show long-term progression in a significant number of cases. In many cases, the progression is substantial and may require a change in pacing mode.

: 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.

: 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.

Aims: Some barriers seem to exist in changing implantable cardioverter defibrillator (ICD) manufacturer at the time of device replacement. We sought to understand the obstacles to changing ICD manufacturer within the cohort of patients enrolled in the Detect Long-term Complications After ICD Replacement Registry., Methods: We analyzed 784 consecutive ICD/cardiac resynchronization therapy defibrillator (CRT-D) device replacements within a 1.5-year time-frame in 36 Italian centers to evaluate potential factors associated with changing manufacturers and system-related complications., Results: Manufacturer change occurred in 191 patients (24%): 72/211 single-chamber ICDs (34%), 52/210 dual-chamber ICDs (25%) and 67/363 CRT-D (18%, P < 0.0001 vs. single-chamber). Replacement-only procedures were associated with a lower rate of manufacturer change than upgrading procedures (23 vs. 32%, P = 0.02). In the single-chamber/dual-chamber cohort, the only variables associated with manufacturer change were the number of available manufacturers (OR = 1.9; P < 0.0001) and an upgrade procedure (OR = 1.7; P = 0.035), whereas the center volume was associated with maintenance of the same manufacturer (OR = 0.5; P = 0.0172). In the CRT-D group, the number of available manufacturers [OR = 2.9; P < 0.0001, service life below the median value (OR = 2.5; P = 0.0026)], and physiological design (OR = 8.4; P = 0.0048) were associated with manufacturer change. At 6-month follow-up, 17 patients (2.2%) experienced a system complication that was lead-related in all cases; upgrade procedure was the only predictor (hazard ratio = 6.7) of complications., Conclusion: At the time of ICD replacement, a manufacturer change occurred in 24% of patients and it was less likely in CRT-D devices, which are equipped with more specific technology and less frequently require the addition of features. System-related complications are strongly associated to upgrade procedures rather than to manufacturer change.

Aim: Cardiac resynchronization is a well tolerated and effective therapy for heart failure, but 30% of patients still do not respond to biventricular pacing. Optimization of device settings, in particular interventricular delay value, represents a plausible target for improving these results, but available literature is discordant. We aimed our study at the identification of the best suitable candidates to interventricular delay optimization., Methods: A total of 77 consecutive patients with optimized drugs therapy underwent clinical, echocardiographic and electrocardiographic evaluation before and after 6 months from implantation of a biventricular defibrillator in accordance to current guidelines. In each patient, atrioventricular and interventricular delay values were optimized at predischarge with echocardiogram., Results: The only predictor of an optimized interventricular delay value different from simultaneous (i.e. standard shipment setting), at both univariate and multivariate analyses, was a QRS duration greater than 160 ms (odds ratio 22.958; P = 0.003) with a sensitivity of 70.9%., Conclusion: Candidates to cardiac resynchronization therapy with a basal QRS greater than 160 ms have a higher chance of requiring echo-guided tailoring of interventricular delay value. A strategy based on these data can potentially improve device programming, reducing by one-third the need for optimization, according to our findings, and at the same time avoid unnecessary time-consuming procedures.

The Biventricular versus Right Ventricular Pacing in Heart Failure Patients with Atrioventricular Block (BLOCK HF) trial, published in April 2013 [Curtis AB, Worley SJ, Adamson PB, et al; Biventricular versus Right Ventricular Pacing in Heart Failure Patients with Atrioventricular Block (BLOCK HF) Trial Investigators. Biventricular pacing for atrioventricular block and systolic dysfunction. N Engl J Med 2013; 368:1585-1593], explored whether cardiac resynchronization therapy (CRT) was superior to conventional pacing in patients with conventional indications for pacing, left ventricular dysfunction and NYHA (New York Heart Association) class I-III. The trial took 8 years and a source of concern is selection bias, because participating centers had an average of two patients enrolled per center, per year. Both the internal and external validity of the trial merit some comments. BLOCK HF showed a relatively low treatment effect of CRT as compared with other CRT trials. As a matter of fact, the absolute risk reduction for death or hospitalization because of heart failure was 4.8%, in a relatively long follow-up, with a number needed to treat (NNT) of 21, much higher than the NNT of other CRT trials. We estimate that at least one third of patients in BLOCK HF could meet current indications for CRT. Moreover, the study did not consider the additional risks and costs of CRT versus conventional pacing, both having important implications for cost-effectiveness estimates. For these and other reasons, uncertainties arise as to how far BLOCK HF extends current recommendations for CRT and how much it should be implemented in daily clinical practice.

The number of cardiac implantable electronic devices (CIEDs) has greatly increased in the last 10 years. Many electronic devices used in daily activities generate electromagnetic interferences (EMIs) that can interact with CIEDs. In clinical practice, it is very important to know the potential sources of EMIs and their effect on CIEDs in order to understand how to manage or mitigate them. A very important source of EMI is magnetic resonance (MR), which is considered nowadays the diagnostic gold standard for different anatomical districts. In this review, we focused on the effects of EMI on CIEDs and on the clinical management. Moreover, we made a clarification about MR and CIEDs.In patients with CIEDs, EMIs may cause potentially serious and even life-threatening complications (inappropriate shocks, device malfunctions, inhibition of pacing in pacemaker-dependent patients) and may rarely dictate device replacement. The association of inappropriate shocks with increased mortality highlights the importance of minimizing the occurrence of EMI. Adequate advice and recommendations about the correct management of EMIs in patients with CIEDs are required to avoid all complications during hospitalization and in daily life. Furthermore, the article focused on actual management about MR and CIEDs.

Aims: To evaluate the potential impact of the different definitions of non-valvular atrial fibrillation reported in the literature and to analyse the possible implications for eligibility for novel oral anticoagulants (NOACs) in clinical practice., Methods: We derived the definitions of 'non-valvular atrial fibrillation' from the exclusion criteria of the trials on NOACs, and then assessed the number and percentage of patients fulfilling the various definitions in a cohort of 500 consecutive atrial fibrillation patients, undergoing clinical and echocardiographic evaluation in our cardiology department, as either in-patients or out-patients., Results: Among the 500 atrial fibrillation patients (mean age 71.2 ± 12.6 years), with permanent atrial fibrillation in 45.2% of the cases, hypertension was very common, either as the main diagnosis or as an associated disease. Valvular heart disease as the main diagnosis (including valvular prosthesis) accounted for 22.8% of the cases. At the echocardiographic evaluation, valvular alterations were very common, especially mitral regurgitation (present, with a variable degree of severity in 63.6% of the cases). Application of the RE-LY exclusion criteria with regard to valvular disease resulted in 116 (23.2%) patients of our cohort classified as valvular atrial fibrillation. This percentage was reduced to 12.2 and 8.8% if ROCKET-AF and ARISTOTLE/ENGAGE-AF criteria, respectively, were applied., Conclusions: Non-valvular atrial fibrillation is a common clinical entity, but without a unified definition in the literature. The impact in daily practice of the different definitions adopted in trials is noteworthy, since in one patient out of seven, the eligibility for NOACs can be questioned, simply as a consequence of adopting a more or less restrictive definition.

The increase in incidence/prevalence of infections of implantable pacemakers and defibrillators (implantable cardioverter defibrillator, ICD) is outweighing that of the implanting procedures, mainly favored by the changes in patient profile. Despite the high impact on patient's outcome and related costs for healthcare systems, we lack specific evidence on the preventive measures with the exception of antibiotic prophylaxis. The aim of this study is to focus on common approaches to pacemaker/ICD implantation to identify the practical preventive strategies and choices that can (potentially) impact on the occurrence of this feared complication. After a brief introduction on clinical presentation, pathogenesis, and risk factors, we will present the results from a survey on the preventive strategies adopted by different operators from the 25 centers of the Emilia Romagna region in the northern Italy (4.4 million inhabitants). These data will provide the basis for reviewing available literature on this topic and identifying the gray areas. The last part of the article will cover the available evidence about pacemaker/ICD implantation, focusing on prophylaxis of pacemaker/ICD infection as a 'continuum' starting before the surgical procedure (from indications to patient preparation), which follows during (operator, room, and techniques) and after the procedure (patient and device follow-up). We will conclude by evaluating the relationship between adherence to the available evidence and the volume of procedures of the implanting centers or operators' experience according to the results of our survey.

Background: Consensus guidelines define indications for cardiac resynchronization therapy (CRT), but the variability in implant rates in 'real world' clinical practice, as well as the relationship with the epidemiology of heart failure are not defined., Methods and Results: In Emilia-Romagna, an Italian region with around 4.4 million inhabitants, a registry was instituted to collect data on implanted devices for CRT, with (CRT-D) or without defibrillation (CRT-P) capabilities. Data from all consecutive patients resident in this region who underwent a first implant of a CRT device in years 2006-2010 were collected and standardized (considering each of the nine provinces of the region). The number of CRT implants increased progressively, with a 71% increase in 2010 compared to 2006. Between 84 and 90% of implants were with CRT-D devices. The variability in standardized implant rates among the provinces was substantial and the ratio between the provinces with the highest and the lowest implant rates was always greater than 2. Considering prevalent cases of heart failure in the period 2006-2010, the proportion of patients implanted with CRT per year ranged between 0.23 and 0.30%., Conclusions: The application in 'real world' clinical practice of CRT in heart failure is quite heterogeneous, with substantial variability even among areas belonging to the same region, with the need to make the access to this treatment more equitable. Despite the increased use of CRT, its overall rate of adoption is low, if a population of prevalent heart failure patients is selected on the basis of administrative data on hospitalizations.

Background: Phrenic stimulation (PS) may hinder left ventricular (LV) pacing. We prospectively observed its prevalence in consecutive patients with cardiac resynchronization therapy (CRT) devices., Methods and Results: In the years 2003 to 2006, 197 patients received a CRT device. PS and LV threshold measurements were carried out at implantation and at 6-month follow-up. LV reverse remodeling was assessed by echocardiography before implantation and at follow-up. LV lead placement was lateral/posterolateral in 86% of patients. Both PS and LV reverse remodeling occurred most frequently at the lateral/posterolateral LV pacing sites (P<0.001). PS was detected in 73 (37%) of patients and was clinically relevant in 41 (22%). The detection of PS at implantation had a poor sensitivity, as it occurred only in left lateral or sitting position in 27 patients. Ten patients (5%) underwent repeated surgery and 4 (2%) had their CRT turned off because of PS. At follow-up, we could manage PS noninvasively in 32 patients with a small PS-LV threshold difference: in 20 by cathode programmability (3 also thanks to automatic management of LV output) and in 12 (without cathode programmability) by programming the LV output as threshold +1 V., Conclusions: PS may seriously hinder CRT. A bipolar LV lead and cathode programmability are mandatory to avoid PS by changing the LV pacing vector at target sites for CRT. LV stability at target sites despite PS should also be pursued by these means. The automatic adjustment of LV pacing output is complementary in patients with a small PS-LV threshold difference.

Background and Purpose: Emery-Dreifuss muscular dystrophy (EDMD) is a rare inherited disorder associated with cardiac involvement. We investigated the spectrum and relevance of the cardiac manifestations of EDMD, focusing on bradyarrhythmias and tachyarrhythmias (including atrial fibrillation/flutter), embolic stroke, and heart failure., Methods and Results: Eighteen patients (age 42.8+/-19.6 years) with genetically confirmed X-linked (n=10, including 3 carriers) or autosomal dominant (n=8) EDMD were followed for a period ranging from 1 to 30 years in a research center for neuromuscular diseases and in a university cardiological department. Pacemakers were required by 10 of 18 (56%) patients for bradyarrhythmia, and related complications occurred in 3 of 10 (30%) cases. Atrial fibrillation/flutter developed in 11 of 18 (61%) patients, with atrial standstill subsequently occurring in 5 of 11 (45%) cases and embolic stroke (most often disabling) in 4 of 11 (36%). Heart failure requiring transplantation occurred in 1 of 18 (6%) patients, and asymptomatic left ventricular dysfunction in a further 3 (17%). No relationship was evident between neuromuscular impairment and cardiac involvement., Conclusions: Both X-linked and autosomal dominant EDMD patients risk not only bradyarrhythmia (requiring pacemaker implant) but also atrial fibrillation/flutter, which often anticipates atrial standstill and can cause disabling embolic stroke at a relatively young age. Antithromboembolic prophylaxis has to be recommended in EDMD patients with atrial fibrillation/flutter or atrial standstill. With careful monitoring, survival after pacemaker implant may be long. Heart failure, which seems to occur only in a minority of patients, may be severe.

Background: The aims of our study were to investigate the meaning of local atrial activation and its behavior during paroxysmal atrial fibrillation and to study the effect of overdrive pacing on local atrial activity., Methods and Results: Twenty-five patients with lone paroxysmal atrial fibrillation underwent electrophysiological study. Functional and effective atrial refractoriness was determined. Mean and fifth percentile values of 100 consecutive atrial fibrillation intervals (FF) were evaluated at three atrial sites either at arrhythmia onset or at self-termination (or at minute 5). A high-voltage burst pacing was performed after 6 minutes of stable atrial fibrillation in 10 patients. Mean FF intervals were evaluated 5 seconds before and after atrial pacing. Forty-nine atrial fibrillation episodes were induced: 39 self-terminating within 5 minutes and 10 long-lasting. A significant correlation was found between mean FF and atrial functional refractory period (r = .73, P < .001) and between fifth percentile FF and atrial effective refractory period (r = .57, P < .005). Atrial fibrillation self-termination was associated with significant mean FF prolongation, whereas long-lasting fibrillation behaved the opposite. In 10 patients, burst pacing resulted in significant shortening of the mean FF at the stimulation site; no changes were observed in the two distant recording sites., Conclusions: The analysis of the FF intervals demonstrates a strict correlation with atrial functional refractoriness. The self-termination of atrial fibrillation is related to a prolongation of the functional refractoriness (mean FF), whereas a shortening of both functional and effective refractoriness (fifth percentile) is associated with atrial fibrillation persistence. The provoked shortening of the mean FF at the stimulation site is consistent with the presence of a gap of excitability during atrial fibrillation in the human atria.

Objective: To evaluate the humoral response to routine childhood immunization of HIV-infected children., Design: Response rate, antibody titres and persistence after polio and tetanus vaccination were compared in 72 children with HIV seropositivity at birth and divided according to HIV infection status as determined by clinical and laboratory tests., Methods: Polio antibodies were titred in a microneutralization test (positive titres, > or = 1:4), and antibody to tetanus toxoid with a passive haemagglutination method (protective titres, > or = 1:1024)., Results: The response rates to polio and tetanus vaccination (> 80 and > 75%) were similar in the HIV-infected and non-infected children, as were antibody levels. In the subgroup with sera obtained some months after the last dose of vaccine, polio antibody levels decreased in all four HIV-infected and in three of the seven non-infected children; protective tetanus antitoxin levels were detected in three of the six infected and in all three non-infected children., Conclusions: This study demonstrates the ability of children with HIV infection to respond adequately to the two vaccines considered, although tetanus antitoxin levels were inferior, compared with those in the seroreverted children. The unsatisfactory antibody levels observed in the admittedly few HIV-positive children studied some months after the last vaccination could be the result of a lower initial protective level and not necessarily an expression of severely impaired immunocompetence. The administration of booster doses in addition to the traditional immunization schedule could be useful in children with HIV infection.