Sex differences among subcutaneous implantable cardioverter-defibrillator recipients: a propensity-matched, multicentre, international analysis from the i-SUSI project.

AIMS: Women have been historically underrepresented in implantable cardioverter-defibrillator (ICD) trials. No data on sex differences regarding subcutaneous ICDs (S-ICD) carriers have been described. Aim of our study was to investigate sex-related differences among unselected S-ICD recipients. METHODS AND RESULTS: Consecutive patients enrolled in the multicentre, international i-SUSI registry were analysed. Comparisons between sexes were performed using a 1:1 propensity matching adjusted analysis for age, body mass index (BMI), left ventricular function, and substrate. The primary outcome was the rate of appropriate shocks during follow-up. Inappropriate shocks and other device-related complications were deemed secondary outcomes. A total of 1698 patients were extracted from the i-SUSI registry; 399 (23.5%) were females. After propensity matching, two cohorts of 374 patients presenting similar baseline characteristics were analysed. Despite similar periprocedural characteristics and a matched BMI, women resulted at lower risk of conversion failure as per PRAETORIAN score (73.4% vs. 81.3%, P = 0.049). Over a median follow-up time of 26.5 [12.7-42.5] months, appropriate shocks were more common in the male cohort (rate/year 3.4% vs. 1.7%; log-rank P = 0.049), while no significant differences in device-related complications (rate/year: 6.3% vs. 5.8%; log-rank P = 0.595) and inappropriate shocks (rate/year: 4.3% vs. 3.1%; log-rank P = 0.375) were observed. After controlling for confounders, sex remained significantly associated with the primary outcome (aHR 1.648; CI 0.999-2.655, P = 0.048), while not resulting predictor of inappropriate shocks and device-related complications. CONCLUSION: In a propensity-matched cohort of S-ICD recipients, women are less likely to experience appropriate ICD therapy, while not showing higher risk of device-related complications. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT0473876.

Impact of ventricular tachycardia ablation in subcutaneous implantable cardioverter defibrillator carriers: a multicentre, international analysis from the iSUSI project.

AIMS: Catheter ablation (CA) of ventricular tachycardia (VT) has become an important tool to improve clinical outcomes in patients with appropriate transvenous implantable cardioverter defibrillator (ICD) shocks. The aim of our analysis was to test whether VT ablation (VTA) impacts long-term clinical outcomes even in subcutaneous ICD (S-ICD) carriers. METHODS AND RESULTS: International Subcutaneous Implantable Cardioverter Defibrillator (iSUSI) registry patients who experienced either an ICD shock or a hospitalization for monomorphic VT were included in this analysis. Based on an eventual VTA after the index event, patients were divided into VTA+ vs. VTA- cohorts. Primary outcome of the study was the occurrence of a combination of device-related appropriate shocks, monomorphic VTs, and cardiovascular mortality. Secondary outcomes were addressed individually. Among n = 1661 iSUSI patients, n = 211 were included: n = 177 experiencing ICD shocks and n = 34 hospitalized for VT. No significant differences in baseline characteristics were observed. Both the crude and the yearly event rate of the primary outcome (5/59 and 3.8% yearly event rate VTA+ vs. 41/152 and 16.4% yearly event rate in the VTA-; log-rank: P value = 0.0013) and the cardiovascular mortality (1/59 and 0.7% yearly event rate VTA+ vs. 13/152 and 4.7% yearly event rate VTA-; log-rank P = 0.043) were significantly lower in the VTA + cohort. At multivariate analysis, VTA was the only variable remaining associated with a lower incidence of the primary outcome [adjusted hazard ratio 0.262 (0.100-0.681), P = 0.006]. CONCLUSION: In a real-world registry of S-ICD carriers, the combined study endpoint of arrhythmic events and cardiovascular mortality was lower in the patient cohort undergoing VTA at long-term follow-up. CLINICALTRIALS.GOV IDENTIFIER: NCT0473876.

Temporal association between drops in thoracic impedance and malignant ventricular arrhythmia: A longitudinal analysis of remote monitoring trends.

INTRODUCTION: Thoracic impedance (TI) drops measured by implantable cardioverter-defibrillators (ICDs) have been reported to correlate with ventricular tachycardia/fibrillation (VT/VF). The aim of our study was to assess the temporal association of decreasing TI trends with VT/VF episodes through a longitudinal analysis of daily remote monitoring data from ICDs and cardiac resynchronization therapy defibrillators (CRT-Ds). METHODS AND RESULTS: Retrospective data from 2384 patients were randomized 1:1 into a derivation or validation cohort. The TI decrease rate was defined as the percentage of rolling weeks with a continuously decreasing TI trend. The derivation cohort was used to determine a TI decrease rate threshold for a ≥99% specificity of arrhythmia prediction. The associated risk of VT/VF episodes was estimated in the validation cohort by dividing the available follow-up into 60-day assessment intervals. Analyses were performed separately for 1354 ICD and 1030 CRT-D patients. During a median follow-up of 2.0 years, 727 patients (30.4%) experienced 3298 confirmed VT/VF episodes. In the ICD group, a TI decrease rate of >60% was associated with a higher risk of VT/VF episode in a 60-day assessment interval (stratified hazard ratio, 1.42; 95% confidence interval (CI), 1.05-1.92; p = .023). The TI decrease preceded (40.8%) or followed (59.2%) the VT/VF episodes. In the CRT-D group, no association between TI decrease and VT/VF episodes was observed (p = .84). CONCLUSION: In our longitudinal analysis, TI decrease was associated with VT/VF episodes only in ICD patients. Preventive interventions may be difficult since episodes can occur before or after TI decrease.

Leadless Pacemaker Implantation in the Emergency Bradyarrhythmia Setting: Results from a Multicenter European Registry.

Background. Data on leadless pacemaker (LPM) implantation in an emergency setting are currently lacking. Objective. We aimed to investigate the feasibility of LPM implantation for emergency bradyarrhythmia, in patients referred for urgent PM implantation, in a large, multicenter, real-world cohort of LPM recipients. Methods. Two cohorts of LPM patients, stratified according to the LPM implantation scenario (patients admitted from the emergency department (ED+) vs. elective patients (ED−)) were retrieved from the iLEAPER registry. The primary outcome of the study was a comparison of the peri-procedural complications between the groups. The rates of peri-procedural characteristics (overall procedural and fluoroscopic duration) were deemed secondary outcomes. Results. A total of 1154 patients were enrolled in this project, with patients implanted due to an urgent bradyarrhythmia (ED+) representing 6.2% of the entire cohort. Slow atrial fibrillation and complete + advanced atrioventricular blocks were more frequent in the ED+ cohort (76.3% for ED+ vs. 49.7% for ED−, p = 0.025; 37.5% vs. 27.3%, p = 0.027, respectively). The overall procedural times were longer in the ED+ cohort (60 (45−80) mins vs. 50 (40−65) mins, p < 0.001), showing higher rates of temporary pacing (94.4% for ED+ vs. 28.9% for ED−, p < 0.001). Emergency LPM implantation was not correlated with an increase in the rate of major complications compared to the control group (6.9% ED+ vs. 4.2% ED−, p = 0.244). Conclusion. LPM implantation is a feasible procedure for the treatment of severe bradyarrhythmia in an urgent setting. Urgent LPM implantation was not correlated with an increase in the rate of major complications compared to the control group, but it was associated with longer procedural times.

Intraprocedural PRAETORIAN score for early assessment of S-ICD implantation: A proof-of-concept study.

INTRODUCTION: The PRAETORIAN score (PS) was developed to assess the implant position and predict defibrillation success of the subcutaneous implantable cardioverter defibrillators (S-ICD). The main critique moved to the routine use of PS has been its postprocedural timing, that limits its usefulness on procedure guidance. The aim of this proof-of-concept study was to assess the feasibility of an intraprocedural use of PS. METHODS: Forty consecutive patients undergoing S-ICD implantation were enrolled. Intraprocedural PS (IP-PS) obtained with fluoroscopy before closure of the pocket and postprocedural PS (PP-PS) obtained with two-views chest X-ray were compared. Intraprocedural data and PS were compared with the historic cohorts of the involved institutions. RESULTS: When assessing IP-PS and PP-PS, a complete overall agreement was observed (100%, 1.00-κ; p < .001). When assessing a per-step agreement, a very high-degree of concordance in evaluating Step 1 of the PS was observed (95%, 0.81-κ; p < .001). A complete agreement in Step 2-3 (100%, 1.00-κ; p < .001) of the PS was reported. In comparison with our historical cohort, procedural time in the IP-PS cohort did not increase (45 [41-52] vs. 45 [39-49] min; p = .351) while the expected increase in fluoroscopy time resulted scarce (15 [10-15] s). CONCLUSION: An IP-PS can be reliably obtained using fluoroscopy guidance during S-ICD implantation, without a significant increase in procedural duration and may serve as guidance for implanting physicians, to avoid postprocedural S-ICD repositioning, leading to patient discomfort and significantly enhancing infective risks. IP-PS showed a very high agreement with the PP-PS obtained from two-views chest X-ray.

Clinical presentation, diagnosis, and treatment of atrioesophageal fistula resulting from atrial fibrillation ablation.

BACKGROUND: Atrioesophageal fistula (AEF) is a worrisome complication of atrial fibrillation (AF) ablation. Its clinical manifestations and time course are unpredictable and may contribute to diagnostic and treatment delays. We conducted a systematic review of all available cases of AEF, aiming at characterizing clinical presentation, time course, diagnostic pitfalls, and outcomes. METHODS: The digital search retrieved 150 studies containing 257 cases, 238 (92.6%) of which with a confirmed diagnosis of AEF and 19 (7.4%) of pericardioesophageal fistula. RESULTS: The median time from ablation to symptom onset was 21 days (interquartile range [IQR]: 11-28). Neurological abnormalities were documented in 75% of patients. Compared to patients seen by a specialist, those evaluated at a walk-in clinic or community hospital had a significantly greater delay between symptom onset and hospital admission (median: 2.5 day [IQR: 1-8] vs. 1 day [IQR: 1-5); p = .03). Overall, 198 patients underwent a chest scan (computed tomography [CT]: 192 patients and magnetic resonance imaging [MRI]: 6 patients), 48 (24.2%; 46 CT and 2 MRI) of whom had normal/unremarkable findings. Time from hospital admission to diagnostic confirmation was significantly longer in patients with a first normal/unremarkable chest scan (p < .001). Overall mortality rate was 59.3% and 26.0% survivors had residual neurological deficits at the time of discharge. CONCLUSIONS: Since healthcare professionals of any specialty might be involved in treating AEF patients, awareness of the clinical manifestations, diagnostic pitfalls, and time course, as well as an early contact with the treating electrophysiologist for a coordinated interdisciplinary medical effort, are pivotal to prevent diagnostic delays and reduce mortality.

Atrioventricular and intraventricular blocks in the setting of acute coronary syndromes: a narrative review.

Acute coronary syndromes (ACS) might be complicated by atrioventricular (AV) and intraventricular (IV) blocks in a significant number of cases, and often represent a diagnostic and a therapeutic challenge. These conduction disturbances are predictors of adverse prognosis, with complete AV blocks presenting the most severe outcomes, showing an increased in-hospital mortality. With the advent of emergency percutaneous coronary intervention (PCI) and the end of the thrombolysis era, the incidence of both AV and IV blocks has surely decreased, but their prognosis in this setting still remains a matter of debate. The aim of this review is to evaluate the current knowledge on AV and IV blocks in the AMI setting with or without ST segment elevation.

Atrioventricular synchronous leadless pacemaker: state of art and broadened indications.

Leadless pacemakers (LLPMs) have become a major breakthrough in the management of bradyarrhythmia as an attractive alternative to the standard transvenous pacemakers (TV-PMs). Recently, the introduction of a second-generation LLPMs (Micra AV-MC1AVR1) has expanded pacing modes to obtain atrioventricular (AV) synchronous pacing, providing an interesting alternative in the actual scenario of leadless pacing. Nevertheless, actual reports have highlighted some concerns regarding those devices. In this review, we sought to provide an overview of this technology based on its approval studies and major reports.

Second-generation laser balloon ablation for the treatment of atrial fibrillation assessed by continuous rhythm monitoring: the LIGHT-AF study.

AIMS: Balloon-based technologies have been developed to simplify catheter ablation of atrial fibrillation (AF), to improve the clinical outcome of the procedure and to achieve durable pulmonary vein isolation (PVI). The objective of this study is to evaluate the safety and efficacy of second-generation laser balloon (LB2) ablation in the treatment of AF using a continuous cardiac rhythm monitoring strategy. Atrial tachyarrhythmias (ATas) recurrences were assessed with implantable cardiac monitors (ICMs) or devices. METHODS AND RESULTS: All patients underwent LB2 ablation procedure. The primary endpoint was the first recurrence of any, >5.5 and >24 h duration ATas after the blanking period (90 days). In-hospital visits were performed at 3, 6, and 12 months. Seventy-three patients (68% male, mean age 59.8 ± 11.3) were included in the study. The average procedure, fluoroscopy, and laser ablation times were 81.5 ± 30.1, 21.5 ± 12.4, and 33.8 ± 9.7, respectively. All PVs were isolated using the LB2 with no need of touch-up using focal catheters. No major complications occurred during or after the procedures. The one-year freedom from recurrences was 66.9% (95% CI: 57.0-76.7%), 81.0% (69.5-88.5%), and 86.8% (76.1-92.9%) considering any, 5.5-h and 24-h cut-off duration, respectively. At 3, 6, and 12 months, any ATas was recorded in 22%, 32%, and 25% of patients, with a ≥5% arrhythmic burden documented in 4%, 5%, and 3%, respectively. Few patients reported AF-related symptoms (7%, 8%, and 5%). CONCLUSION: LB2 ablation is a safe and effective procedure, showing a high freedom from recurrences and low arrhythmic burden as documented by a continuous rhythm monitoring strategy.

Targeting non-pulmonary vein triggers in persistent atrial fibrillation: results from a prospective, multicentre, observational registry.

AIMS: We evaluated the efficacy of an ablation strategy empirically targeting pulmonary veins (PVs) and posterior wall (PW) and the prevalence and clinical impact of extrapulmonary trigger inducibility and ablation in a large cohort of patients with persistent atrial fibrillation (PerAF). METHODS AND RESULTS: A total of 1803 PerAF patients were prospectively enrolled. All patients underwent pulmonary vein antrum isolation (PVAI) extended to the entire PW. A standardized protocol was performed to confirm persistent PVAI and elicit any triggers originating from non-PV sites. All non-PV triggers initiating sustained atrial tachyarrhythmias were ablated. Ablation of non-PV sites triggering non-sustained runs (<30 s) of atrial tachyarrhythmias or promoting frequent premature atrial complexes (≥10/min) was left to operator's discretion. Overall, 1319 (73.2%) patients had documented triggers from non-PV areas. After 17.4 ± 8.5 months of follow-up, the cumulative freedom from atrial tachyarrhythmias among patients without inducible non-PV triggers (n = 484) was 70.2%. Patients with ablation of induced non-PV triggers had a significantly higher arrhythmia control than those whose triggers were not ablated (67.9% vs. 39.4%, respectively; P < 0.001). After adjusting for clinically relevant variables, patients in whom non-PV triggers were documented but not ablated had an increased risk of arrhythmia relapse (hazard ratio: 2.39; 95% confidence interval: 2.01-2.83; P < 0.001). CONCLUSION: Pulmonary vein antrum isolation extended to the entire PW might provide acceptable long-term arrhythmia-free survival in PerAF patients without inducible non-PV triggers. In our population of PerAF patients, non-PV triggers could be elicited in ∼70% of PerAF patients and their elimination significantly improved outcomes.

Catheter Ablation of Life-Threatening Ventricular Arrhythmias in Athletes.

A recent surveillance analysis indicates that cardiac arrest/death occurs in ≈1:50,000 professional or semi-professional athletes, and the most common cause is attributable to life-threatening ventricular arrhythmias (VAs). It is critically important to diagnose any inherited/acquired cardiac disease, including coronary artery disease, since it frequently represents the arrhythmogenic substrate in a substantial part of the athletes presenting with major VAs. New insights indicate that athletes develop a specific electro-anatomical remodeling, with peculiar anatomic distribution and VAs patterns. However, because of the scarcity of clinical data concerning the natural history of VAs in sports performers, there are no dedicated recommendations for VA ablation. The treatment remains at the mercy of several individual factors, including the type of VA, the athlete's age, and the operator's expertise. With the present review, we aimed to illustrate the prevalence, electrocardiographic (ECG) features, and imaging correlations of the most common VAs in athletes, focusing on etiology, outcomes, and sports eligibility after catheter ablation.

Neglected lead tip erosion: An unusual case of S-ICD inappropriate shock.

A 52-year-old man experienced a subcutaneous implantable cardioverter-defibrillator (S-ICD) inappropriate shock due to electrode tip decubitus. The device, implanted two years before with a three-incision technique, was extracted, and a new electrode was implanted along the contralateral parasternal line with a two-incision technique, in a one-stage procedure. One-year follow-up was eventless. Early S-ICD electrode extraction and reimplantation during the same procedure is effective and should be considered as soon as initial signs of decubitus appear to avoid inappropriate shocks. A two-incision technique should be preferred to reduce the risk of electrode tip decubitus.

Clinical and economic impact of multipoint left ventricular pacing: A comparative analysis from the Italian registry on multipoint pacing in cardiac resynchronization therapy (IRON-MPP).

INTRODUCTION: Early evidence suggests that multipoint left ventricular pacing (MPP) may improve response to cardiac resynchronization therapy (CRT). It is unknown whether this benefit is sustained and cost-effective. We used real-world data to evaluate long-term impact of MPP-ON clinical status, heart failure hospitalizations (HFH) and costs. METHODS: The Italian registry on multipoint left ventricular pacing is a prospective, multicenter registry of patients implanted with MPP-enabled CRT devices. For this analysis, clinical and echocardiographic data were collected through 24 months and compared between patients with (MPP-ON) or without (MPP-OFF) early MPP activation at implant. The total cost of each HFH was estimated with national Italian reimbursement rates. RESULTS: The study included 190 MPP-OFF and 128 MPP-ON patients with similar baseline characteristics. At 1 and 2 years, the MPP-ON group had lower rates of HFH vs MPP-OFF (1-year hazard ratio [HR]: 0.14, P = .0014; 2-year HR: 0.38, P = .009). The finding persisted in a subgroup of patients with consistent MPP activation through follow-up (1-year HR: 0.19; P = .0061; 2-year HR: 0.39, P = .022). Total HFH per-patient costs were lower in the MPP-ON vs the MPP-OFF group at 1 year (€101 ± 50 vs €698 ± 195, P < .001) and 2 years (€366 ± 149 vs €801 ± 203, P = .038). More MPP-ON patients had ≥5% improvement in ejection fraction (76.8% vs 65.4%, P = .025) and clinical composite score (66.7% vs 47.5%, P = .01). CONCLUSIONS: In this multicenter clinical study, early MPP activation was associated with a significant reduction in cumulative HFH and related costs after 1 and 2 years of follow-up.

Impact of multipoint pacing on projected battery longevity in cardiac resynchronization therapy. An IRON-MPP study sub-analysis.

BACKGROUND: Multipoint pacing (MPP) may improve clinical outcomes in patients with cardiac resynchronization therapy defibrillators (CRT-D), but its impact on battery longevity in a real-world population has not been investigated in large trials. OBJECTIVE: Compare projected battery longevity in CRT-D patients with and without MPP during long-term follow-up. METHODS: The Italian registry on multipoint left ventricular pacing (IRON-MPP) is a prospective, multicenter registry of patients implanted with MPP-capable CRT-D devices. Projected battery longevity during follow-up was compared for patients with MPP (MPP ON) vs single-site (MPP OFF) left ventricular pacing at CRT-D implantation. A sub-analysis excluded crossover patients with MPP activation or deactivation occurring after implantation. A second sub-analysis excluded patients with a right or left ventricular pacing amplitude >2.5 V. RESULTS: Out of 237 CRT-D patients (71 ± 9 years, 81% male) followed for 1.9 ± 0.8 years, 102 (43%) had MPP ON at implantation. Programmed atrial and ventricular outputs and percentage of pacing were similar between groups. MPP was associated with a 0.44 years reduction in projected battery longevity (P = .03) during long-term follow-up. Results were similar for the first and second sub-analyses, with a 0.57 years (P < .001) and 0.71 years (P < .001) reduction in projected longevity, respectively. CONCLUSION: In this long-term real-world registry, early MPP activation is associated with less than a 1-year reduction in projected battery life compared to single-site biventricular pacing.

Long-term outcomes after prophylactic ICD and CRT-D implantation in nonischemic patients: Analysis from a nationwide database of daily remote-monitoring transmissions.

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.

The Italian subcutaneous implantable cardioverter-defibrillator survey: S-ICD, why not?

AIMS: A recommendation for a subcutaneous-implantable cardioverter-defibrillator (S-ICD) has been added to recent European Society of Cardiology Guidelines. However, the S-ICD is not ideally suitable for patients who need pacing. The aim of this survey was to analyse the current practice of ICD implantation and to evaluate the actual suitability of S-ICD. METHODS AND RESULTS: The survey 'S-ICD Why Not?' was an independent initiative taken by the Italian Heart Rhythm Society (AIAC). Clinical characteristics, selection criteria, and factors guiding the choice of ICD type were collected in consecutive patients who underwent ICD implantation in 33 Italian centres from September to December 2015. A cardiac resynchronization therapy (CRT) device was implanted in 39% (369 of 947) of patients undergoing de novo ICD implantation. An S-ICD was implanted in 12% of patients with no CRT indication (62 of 510 with available data). S-ICD patients were younger than patients who received transvenous ICD, more often had channelopathies, and more frequently received their device for secondary prevention of sudden death. More frequently, the clinical reason for preferring a transvenous ICD over an S-ICD was the need for pacing (45%) or for antitachycardia pacing (36%). Nonetheless, only 7% of patients fulfilled conditions for recommending permanent pacing, and 4% of patients had a history of monomorphic ventricular tachycardia that might have been treatable with antitachycardia pacing. CONCLUSION: The vast majority of patients needing ICD therapy are suitable candidates for S-ICD implantation. Nevertheless, it currently seems to be preferentially adopted for secondary prevention of sudden death in young patients with channelopathies.

Multipoint pacing via a quadripolar left-ventricular lead: preliminary results from the Italian registry on multipoint left-ventricular pacing in cardiac resynchronization therapy (IRON-MPP).

AIMS: This registry was created to describe the experience of 76 Italian centres with a large cohort of recipients of multipoint pacing (MPP) capable cardiac resynchronization therapy (CRT) devices. METHODS AND RESULTS: A total of 507 patients in whom these devices had been successfully implanted were enrolled between August 2013 and May 2015. We analysed: (i) current clinical practices for the management of such patients, and (ii) the impact of MPP on heart failure clinical composite response and on the absolute change in ejection fraction (EF) at 6 months. Multipoint pacing was programmed to 'ON' in 46% of patients before discharge. Methods of optimizing MPP programming were most commonly based on either the greatest narrowing of the QRS complex (38%) or the electrical delays between the electrodes (34%). Clinical and echocardiographic follow-up data were evaluated in 232 patients. These patients were divided into two groups according to whether MPP was programmed to 'ON' (n = 94) or 'OFF' (n = 138) at the time of discharge. At 6 months, EF was significantly higher in the MPP group than in the biventricular-pacing group (39.1 ± 9.6 vs. 34.7 ± 7.6%; P < 0.001). Even after adjustments, early MPP activation remained an independent predictor of absolute increase in LVEF of ≥5% (odds ratio 2.5; P = 0.001). At 6 months, an improvement in clinical composite score was recorded in a greater proportion of patients with MPP-ON than in controls (56 vs. 38%; P = 0.009). On comparing optimal MPP and conventional vectors, QRS was also seen to have decreased significantly (P < 0.001). CONCLUSION: This study provides information that is essential in order to deal with the expected increase in the number of patients receiving MPP devices in the coming years. The results revealed different practices among centres, and establishing the optimal programming that can maximize the benefit of MPP remains a challenging issue. Compared with conventional CRT, MPP improved clinical status and resulted in an additional increase in EF. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrial.gov/. Unique identifier: NCT02606071.

Hospitalization rates and associated cost analysis of cardiac resynchronization therapy with an implantable defibrillator and quadripolar vs. bipolar left ventricular leads: a comparative effectiveness study.

AIMS: This study compares, from a prospective, observational, non-randomized registry, the post-implant hospitalization rates and associated healthcare resource utilization of cardiac resynchronization therapy-defibrillator (CRT-D) patients with quadripolar (QUAD) vs. bipolar (BIP) left ventricular (LV) leads. METHODS AND RESULTS: Between January 2009 and December 2012, 193 consecutive patients receiving de novo CRT-D implants with either a QUAD (n = 116) or a BIP (n = 77) LV lead were enrolled at implant and followed until July 2013 at a single-centre, university hospital. Post-implant hospitalizations related to heart failure (HF) or LV lead surgical revision and associated payer costs were identified using ICD-9-CM diagnosis and procedure codes. Italian national reimbursement rates were determined. Propensity scores were estimated using a logistic regression model based upon 11 pre-implant baseline characteristics and were used to derive a 1 : 1 matched cohort of QUAD (n = 77) and BIP (n = 77) patients. Hospitalization rates for the two groups were compared using negative binomial regression and associated payer costs were compared using non-parametric bootstrapping (×10 000) and one-sided hypothesis test. Hospitalization rates of the QUAD group [0.15/ patient (pt)-year] were lower than those of the BIP group (0.32/ pt-year); the incidence rate ratio was 0.46, P = 0.04. The hospitalization costs for the QUAD group (434 ± 128 €/pt-year) were lower than those for the BIP group (1136 ± 362 €/pt-year). The average difference was 718 €/pt-year, P = 0.016. CONCLUSIONS: In this comparative effectiveness assessment of well-matched groups of CRT-D patients with quadripolar and bipolar LV leads, QUAD patients experienced a lower rate of hospitalizations for HF and LV lead surgical revision, and a lower cost burden. This has important implications for LV pacing lead choice.

Catheter ablation of atrial fibrillation in patients with mechanical mitral valve: long-term outcome of single procedure of pulmonary vein antrum isolation with or without nonpulmonary vein trigger ablation.

INTRODUCTION: It is unclear whether extended pulmonary vein antrum isolation (PVAI) plus nonpulmonary vein (non-PV) trigger elimination prevents more arrhythmia recurrence than PVAI alone in patients with mechanical mitral valve (MMV) undergoing AF ablation. This study compared the efficacy and long-term outcome of 2 ablation strategies--PVAI alone versus extended PVAI plus non-PV trigger elimination--for the treatment of AF in patients with MMV. METHODS AND RESULTS: One hundred and nine consecutive AF patients with MMV were divided into 2 groups: standard PVAI was performed in group 1 (N = 45); in group 2 (N = 64) PVAI was extended to the LA posterior wall, LA septum, and CS; and all non-PV triggers were eliminated. Patients were followed up for 3 years. At the 12th month, 7 (15.6%) patients in group 1, and 39 (60.9%) patients in group 2 were arrhythmia free (log-rank P < 0.001). Four patients (8.9%; 3 cases of AT and 1 case of AF) from group 1, and 12 patients (18.8%; 9 cases of AT, and 3 cases of AFL) from group 2 experienced very late recurrence. At 36 ± 7 months follow-up, the cumulative recurrence after a single procedure was 42/45 (93.3%) in group 1, and 37/64 (57.8%) in group 2 (log-rank P < 0.001). CONCLUSION: Compared with the standard PVAI alone, a strategy including extended PVAI and non-PV trigger elimination is associated with a higher 12-month and long-term arrhythmia-free survival in patients with MMV undergoing AF ablation. Very late recurrence may occur years after the initial procedure with focal AT as the most common type of recurrent arrhythmia.