Twenty-year experience of atrial fibrillation ablation: a single-centre cohort study.

AIMS: While several studies in the literature have reported results of catheter ablation of AF, few is known regarding outcome for more than 10 years. METHODS AND RESULTS: The complete population of patients who underwent AF ablation in the years 2002-2021 in the department of cardiology of the hospital of Reggio Emilia has been analysed. The last follow-up was made in the second half of 2022. During this period the technique of ablation remained relatively unchanged as well the physicians performing ablation. Primary endpoint was the recurrence of symptomatic AF, defined as AF that caused symptoms that were defined by the patient as able to alter their quality of life. 669 patients underwent catheter ablation and 618 were followed until 2022. Median age of the patients was 58 ± 9 years and 521 (78%) were male. There were 407 (61%) of patients with paroxysmal AF, 167 (25%) with persistent AF and 95 (14%) with long-lasting AF. A total of 838 procedures were performed, with a mean of 1.25 per patient. 163 (26%) patients had 2 procedures and 6 had 3 ablations. Periprocedural complications occurred in 4.8% of procedures. Follow-up data were available for 618 patients (92.4%). The median follow-up duration was 6.6 years (IQR 3.2-10.8). The estimated recurrence rate of symptomatic AF was 26% at 10 years, 54% at 15 years and 82% at 20 years. The recurrence rate was similar in patients who had performed one procedure and in those who had performed 2 or 3 procedures. Progression to permanent AF occurred in 112 patients (18%). The major events that occurred during the follow-up consisted of total mortality in 4.5%, heart failure in 3.1% and TIA/stroke in 2.4%. CONCLUSION: Symptomatic AF tends to recur during long-term follow-up despite one or more procedures. Catheter ablation seems able to reduce the rate of symptomatic recurrences and to delay the time of their occurrence. These findings are consistent with the knowledge that an age-dependent progressive structural atriomiopathy is the basis for the development of AF.

New insertable cardiac monitors show high diagnostic yield and good safety profile in real-world clinical practice: results from the international prospective observational SMART Registry.

AIMS: Insertable cardiac monitors (ICMs) are indicated for long-term monitoring of unexplained syncope or palpitations, and for detection of bradycardia, ventricular tachycardia, and/or atrial fibrillation (AF). The aim of our study was to evaluate the safety and clinical value associated with a new generation ICM (Confirm Rx™, Abbott, Illinois, USA), featuring a new remote monitoring system based on smartphone patient applications. METHODS AND RESULTS: The SMART Registry is an international prospective observational study. The main endpoints were ICM safety (incidence of serious adverse device and procedure-related events (SADEs) at 1 month), ICM clinical value (incidence of device-detected true arrhythmias and of clinical diagnoses and interventions), and patient-reported experience measurements (PREMs). A total of 1400 subjects were enrolled. ICM indications included syncope (49.1%), AF (18.8%), unexplained palpitations (13.6%), risk of ventricular arrhythmia (6.6%), and cryptogenic stroke (6.0%). Freedom from SADEs at 1 month was 99.4% (95% Confidence Interval: 98.8-99.7%). In the 6-month monitoring period, the ICM detected true cardiac arrhythmias in 45.7% of patients and led to clinical interventions in a relevant proportion of patients; in particular, a pacemaker implant was performed after bradycardia detection in 8.9% of subjects who received an ICM for syncope and oral anticoagulation therapy was indicated after AF detection in 15.7% of subjects with cryptogenic stroke. PREMs showed that 78.2% of subjects were satisfied with the remote monitoring patient app. CONCLUSION: The evaluated ICM is associated with an excellent safety profile and high diagnostic yield. Patients reported positive experiences associated with the use of their smartphone for the device remote monitoring.

Ability to remotely monitor atrial high-rate episodes using a single-chamber implantable cardioverter-defibrillator with a floating atrial sensing dipole.

AIMS: To allow timely initiation of anticoagulation therapy for the prevention of stroke, the European guidelines on atrial fibrillation (AF) recommend remote monitoring (RM) of device-detected atrial high-rate episodes (AHREs) and progression of arrhythmia duration along pre-specified strata (6 min…<1 h, 1 h…<24 h, ≥ 24 h). We used the MATRIX registry data to assess the capability of a single-lead implantable cardioverter-defibrillator (ICD) with atrial sensing dipole (DX ICD system) to follow this recommendation in patients with standard indication for single-chamber ICD. METHODS AND RESULTS: In 1841 DX ICD patients with daily automatic RM transmissions, electrograms of first device-detected AHREs per patient in each duration stratum were adjudicated, and the corresponding positive predictive values (PPVs) for the detections to be true atrial arrhythmia were calculated. Moreover, the incidence and progression of new-onset AF was assessed in 1451 patients with no AF history. A total of 610 AHREs ≥6 min were adjudicated. The PPV was 95.1% (271 of 285) for episodes 6min…<1 h, 99.6% (253/254) for episodes 1 h…<24 h, 100% (71/71) for episodes ≥24 h, or 97.5% for all episodes (595/610). The incidence of new-onset AF was 8.2% (119/1451), and in 31.1% of them (37/119), new-onset AF progressed to a higher duration stratum. Nearly 80% of new-onset AF patients had high CHA2DS2-VASc stroke risk, and 70% were not on anticoagulation therapy. Age was the only significant predictor of new-onset AF. CONCLUSION: A 99.7% detection accuracy for AHRE ≥1 h in patients with DX ICD systems in combination with daily RM allows a reliable guideline-recommended screening for subclinical AF and monitoring of AF-duration progression.

Artificial intelligence cloud platform improves arrhythmia detection from insertable cardiac monitors to 25 cardiac rhythm patterns through multi-label classification.

BACKGROUND: Electrocardiogram (ECG) is the gold standard for the diagnosis of cardiac arrhythmias and other heart diseases. Insertable cardiac monitors (ICMs) have been developed to continuously monitor cardiac activity over long periods of time and to detect 4 cardiac patterns (atrial tachyarrhythmias, ventricular tachycardia, bradycardia, and pause). However, interpretation of ECG or ICM subcutaneous ECG (sECG) is time-consuming for clinicians. Artificial intelligence (AI) classifies ECG and sECG with high accuracy in short times. OBJECTIVE: To demonstrate whether an AI algorithm can expand ICM arrhythmia recognition from 4 to many cardiac patterns. METHODS: We performed an exploratory retrospective study with sECG raw data coming from 20 patients wearing a Confirm Rx™ (Abbott, Sylmar, USA) ICM. The sECG data were recorded in standard conditions and then analyzed by AI (Willem™, IDOVEN, Madrid, Spain) and cardiologists, in parallel. RESULTS: In nineteen patients, ICMs recorded 2261 sECGs in an average follow-up of 23 months. Within these 2261 sECG episodes, AI identified 7882 events and classified them according to 25 different cardiac rhythm patterns with a pondered global accuracy of 88%. Global positive predictive value, sensitivity, and F1-score were 86.77%, 83.89%, and 85.52% respectively. AI was especially sensitive for bradycardias, pauses, rS complexes, premature atrial contractions, and inverted T waves, reducing the median time spent to classify each sECG compared to cardiologists. CONCLUSION: AI can process sECG raw data coming from ICMs without previous training, extending the performance of these devices and saving cardiologists' time in reviewing cardiac rhythm patterns detection.

Reducing the electrogram review burden imposed by insertable cardiac monitors.

BACKGROUND: Insertable cardiac monitors (ICMs) are essential for ambulatory arrhythmia diagnosis. However, definitive diagnoses still require time-consuming, manual adjudication of electrograms (EGMs). OBJECTIVE: To evaluate the clinical impact of selecting only key EGMs for review. METHODS: Retrospective analyses of randomly selected Abbott Confirm Rx™ devices with ≥90 days of remote transmission history were performed, with each EGM adjudicated as true or false positive (TP, FP). For each device, up to 3 "key EGMs" per arrhythmia type per day were prioritized for review based on ventricular rate and episode duration. The reduction in EGMs and TP days (patient-days with at least one TP EGM), and any diagnostic delay (from the first TP), were calculated versus reviewing all EGMs. RESULTS: In 1000 ICMs over a median duration of 8.1 months, at least one atrial fibrillation (AF), tachycardia, bradycardia, or pause EGM was transmitted by 424, 343, 190, and 325 devices, respectively, with a total of 95 716 EGMs. Approximately 90% of episodes were contributed by 25% of patients. Key EGM selection reduced EGM review burden by 43%, 66%, 77%, and 50% (55% overall), while reducing TP days by 0.8%, 2.1%, 0.2%, and 0.0%, respectively. Despite reviewing fewer EGMs, 99% of devices with a TP EGM were ultimately diagnosed on the same day versus reviewing all EGMs. CONCLUSION: Key EGM selection reduced the EGM review substantially with no delay-to-diagnosis in 99% of patients exhibiting true arrhythmias. Implementing these rules in the Abbott patient care network may accelerate clinical workflow without compromising diagnostic timelines.

AV junction ablation and cardiac resynchronization for patients with permanent atrial fibrillation and narrow QRS: the APAF-CRT mortality trial.

AIMS: In patients with atrial fibrillation (AF) and heart failure (HF), strict and regular rate control with atrioventricular junction ablation and biventricular pacemaker (Ablation + CRT) has been shown to be superior to pharmacological rate control in reducing HF hospitalizations. However, whether it also improves survival is unknown. METHODS AND RESULTS: In this international, open-label, blinded outcome trial, we randomly assigned patients with severely symptomatic permanent AF >6 months, narrow QRS (≤110 ms) and at least one HF hospitalization in the previous year to Ablation + CRT or to pharmacological rate control. We hypothesized that Ablation + CRT is superior in reducing the primary endpoint of all-cause mortality. A total of 133 patients were randomized. The mean age was 73 ± 10 years, and 62 (47%) were females. The trial was stopped for efficacy at interim analysis after a median of 29 months of follow-up per patient. The primary endpoint occurred in 7 patients (11%) in the Ablation + CRT arm and in 20 patients (29%) in the Drug arm [hazard ratio (HR) 0.26, 95% confidence interval (CI) 0.10-0.65; P = 0.004]. The estimated death rates at 2 years were 5% and 21%, respectively; at 4 years, 14% and 41%. The benefit of Ablation + CRT of all-cause mortality was similar in patients with ejection fraction (EF) ≤35% and in those with >35%. The secondary endpoint combining all-cause mortality or HF hospitalization was significantly lower in the Ablation + CRT arm [18 (29%) vs. 36 (51%); HR 0.40, 95% CI 0.22-0.73; P = 0.002]. CONCLUSIONS: Ablation + CRT was superior to pharmacological therapy in reducing mortality in patients with permanent AF and narrow QRS who were hospitalized for HF, irrespective of their baseline EF. STUDY REGISTRATION: ClinicalTrials.gov Identifier: NCT02137187.

Circadian periodicity affects the type of ventricular arrhythmias and efficacy of implantable defibrillator therapies.

INTRODUCTION: Factors influencing malignant arrhythmia onset are not fully understood. We explored the circadian periodicity of ventricular arrhythmias (VAs) in patients with implantable cardioverter and cardiac resynchronization defibrillators (ICD/CRT-D). METHODS: Time, morphology (monomorphic/polymorphic), and mode of termination (anti-tachycardia pacing [ATP] or shock) of VAs stored in a database of remote monitoring data were adjudicated. Episodes were grouped in six 4-h timeslots from 00:00 to 24:00. Circadian distributions and adjusted marginal odds ratios (ORs), with 95% confidence interval (CI), were analyzed using mixed-effect models and logit generalized estimating equations, respectively, to account for within-subject correlation of multiple episodes. RESULTS: Among 1303 VA episodes from 446 patients (63% ICD and 37% CRT-D), 120 (9%) self-extinguished, and 842 (65%) were terminated by ATP, 343 (26%) by shock. VAs clustered from 08:00 to 16:00 with 44% of episodes, as compared with 22% from 00:00 to 08:00 (p < .001) and 34% from 16:00 to 24:00 (p = .005). Episodes were more likely to be polymorphic at night with an adjusted marginal OR of 1.66 (CI, 1.15-2.40; p = .007) at 00:00-04:00 versus other timeslots. Episodes were less likely to be terminated by ATP in the 00:00-04:00 (success-to-failure ratio, 0.67; CI, 0.46-0.98; p = .039) and 08:00-12:00 (0.70; CI, 0.51-0.96; p = .02) timeslots, and most likely to be terminated by ATP between 12:00 and 16:00 (success-to-failure ratio 1.42; CI, 1.06-1.91; p = .02). CONCLUSION: VAs did not distribute uniformly over the 24 h, with a majority of episodes occurring from 08:00 to 16:00. Nocturnal episodes were more likely to be polymorphic. The efficacy of ATP depended on the time of delivery.

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.

Real-life outcome of implantable cardioverter-defibrillator and cardiac resynchronization defibrillator replacement/upgrade in a contemporary population: observations from the multicentre DECODE registry.

AIMS: The benefit of prolonged implantable cardioverter-defibrillator (ICD)/cardiac resynchronization therapy defibrillator (CRT-D) therapy following device replacement is hindered by clinical and procedure-related adverse events (AEs). Adverse events rate is highest in more complex devices and at upgrades, as per the REPLACE registry experience, but is changing owing to the improvement in device technology and medical care. We aimed at understanding the extent and type of AEs in a contemporary Italian population. METHODS AND RESULTS: Detect long-term complications after ICD replacement (DECODE) was a prospective, single-arm, multicentre cohort study aimed at estimating medium- to long-term AEs in a large population of patients undergoing ICD/cardiac resynchronization defibrillator replacement/upgrade from 2013 to 2015. We prospectively analysed all clinical and device-related AEs at 12-month follow-up (FU) of 983 consecutive patients (median age 71 years, 76% male, 55% ischaemic, 47% CRT-D) followed for 353 ± 49 days. Seven percent of the patients died (60.6% for cardiovascular reasons), whereas 104 AEs occurred; 43 (4.4%) patients needed at least one surgical action to treat the AE. Adverse events rates were 3.3/100 years lead-related, 3.4/100 years bleedings, and 1.6/100 years infective. The primary endpoint was predicted by hospitalization in the month prior to the procedure [hazard ratio (HR) = 2.23, 1.16-4.29; 0.0169] and by upgrade (HR = 1.75, 1.02-2.99, 0.0441). One hundred and twelve (11.4%) patients met the combined endpoint of death from any cause, cardiac implantable electronic device (CIED)-related infection, and surgical action/hospitalization required to treat the AE. Hospitalization within 30 days prior to the procedure (HR = 2.07, 1.13-3.81; 0.0199), anticoagulation (HR = 1.97, 1.26-3.07; 0.003), and ischaemic cardiomyopathy (HR = 1.67, 95% confidence interval 1.06-2.63; P = 0.0276) were associated with the combined endpoint during FU. CONCLUSIONS: Adverse events following CIED replacement/upgrade are lower than previously reported, possibly owing to improved patients care. Hospitalization in the month prior to the procedure, upgrade, and clinical profile (anticoagulation, ischaemic cardiomyopathy) hint to increased risk, suggesting an individualized planning of the procedure to minimize overall AEs. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov/ Identifier: NCT02076789.

A randomized controlled trial of atrioventricular junction ablation and cardiac resynchronization therapy in patients with permanent atrial fibrillation and narrow QRS.

Aims: We tested the hypothesis that atrioventricular (AV) junction ablation in conjunction biventricular pacing [cardiac resynchronization (CRT)] pacing is superior to pharmacological rate-control therapy in reducing heart failure (HF) and hospitalization in patients with permanent atrial fibrillation (AF) and narrow QRS. Methods and results: We randomly assigned 102 patients (mean age 72 ± 10 years) with severely symptomatic permanent AF (>6 months), narrow QRS (≤110 ms), and at least one hospitalization for HF in the previous year to AV junction ablation and CRT (plus defibrillator according to guidelines) or to pharmacological rate-control therapy (plus defibrillator according to guidelines). After a median follow-up of 16 months, the primary composite outcome of death due to HF, or hospitalization due to HF, or worsening HF had occurred in 10 patients (20%) in the Ablation+CRT arm and in 20 patients (38%) in the Drug arm [hazard ratio (HR) 0.38; 95% confidence interval (CI) 0.18-0.81; P = 0.013]. Significantly fewer patients in the Ablation+CRT arm died from any cause or underwent hospitalization for HF [6 (12%) vs. 17 (33%); HR 0.28; 95% CI 0.11-0.72; P = 0.008], or were hospitalized for HF [5 (10%) vs. 13 (25%); HR 0.30; 95% CI 0.11-0.78; P = 0.024]. In comparison with the Drug arm, Ablation+CRT patients showed a 36% decrease in the specific symptoms and physical limitations of AF at 1 year follow-up (P = 0.004). Conclusion: Ablation+CRT was superior to pharmacological therapy in reducing HF and hospitalization and improving quality of life in elderly patients with permanent AF and narrow QRS. ClinicalTrials.gov Identifier: NCT02137187 (May 2018, date last accessed).

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

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

Long-Term Results After Single and Multiple Procedures of Ablation of Ventricular Tachycardia.

INTRODUCTION: The aim of this study was to assess long-term results after single and multiple procedures of catheter ablation of ventricular tachycardia (VT). While it is generally accepted that multiple procedures are sometimes necessary in order to achieve long-term clinical success, the literature on this issue displays wide variability. METHODS: We assessed the outcome of 160 consecutive patients who underwent 214 ablation procedures in the period 2008 to May 2015: 93 had overt structural heart disease (SHD) (previous myocardial infarction in 74 cases) and 67 had no SHD. RESULTS: After the first procedure, the 1-year actuarial recurrence rates were 25% in patients with SHD and 5% in those without. However, recurrences increased progressively after the first year, reaching 46% and 35%, respectively, at 5 years. Overall, VT recurred in 35/93 (38%) patients with SHD and 22/67 (33%) patients without. Redo (1 to 4) procedures were performed in 28 (20%) patients with SHD and 18 (27%) patients without. After the last procedure, the 1-year actuarial recurrence rates were 5% in patients with SHD and 7% in those without, and the corresponding rates at 5 years were 23% and 7%. During follow-up, 21 patients died (all in the SHD group): no death was related to VT recurrence. CONCLUSIONS: During long-term follow-up, VT frequently recurs after the first procedure, both in patients with SHD and in those without; multiple procedures are needed in order to increase the success rate.

Standardized algorithm for cardiac pacing in older patients affected by severe unpredictable reflex syncope: 3-year insights from the Syncope Unit Project 2 (SUP 2) study.

AIMS: The aim of this study was to determine the long-term effects and determinants of success of cardiac pacing in patients affected by reflex syncope enrolled in the Syncope Unit Project 2 (SUP 2) study. Initial results have validated the effectiveness of a standardized guideline-based algorithm which can be used in clinical practice in order to select suitable candidates for cardiac pacing. METHODS AND RESULTS: In this prospective, multicentre, observational study, patients aged >40 years, affected by severe unpredictable recurrent reflex syncope, underwent carotid sinus massage (CSM), followed by tilt testing (TT) if CSM was negative, followed by implantation of an implantable loop recorder (ILR) if TT was negative. Those who had an asystolic response to one of these tests received a dual-chamber pacemaker. Of 281 patients who met the inclusion criteria, 137 (49%) received a pacemaker and were followed up for a mean of 26 ± 11 months: syncope recurred in 25 (18%) of them. At 3 years, the actuarial syncope recurrence rate was 20% [95% confidence interval (CI) 12-30] and was significantly lower than in 142 patients who did not receive a pacemaker and were observed by means of an ILR [43% (95% CI 29-57), P = 0.01]. The 3-year recurrence rate was not different among 78 CSM+, 38 TT+, and 21 ILR+ patients, whereas it was lower in 20 patients with negative TT [5% (95% CI 0-15)] than in 61 patients with positive TT [24% (95% CI 10-38)]. CONCLUSION: The benefit of cardiac pacing is maintained at 3 years, irrespective of the index diagnostic test, and is maximum in patients with negative TT. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01509534.

Automatic management of atrial and ventricular stimulation in a contemporary unselected population of pacemaker recipients: the ESSENTIAL Registry.

AIMS: We investigated the applicability of the Ventricular Capture Control (VCC) and Atrial Capture Control (ACC) algorithms for automatic management of cardiac stimulation featured by Biotronik pacemakers in a broad, unselected population of pacemaker recipients. METHODS AND RESULTS: Ventricular Capture Control and Atrial Capture Control were programmed to work at a maximum adapted output voltage as 4.8 V in consecutive recipients of Biotronik pacemakers. Ambulatory threshold measurements were made 1 and 12 months after pacemaker implant/replacement in all possible pacing/sensing configurations, and were compared with manual measurements. Among 542 patients aged 80 (73-85) years, 382 had a pacemaker implant and 160 a pacemaker replacement. Ventricular Capture Control could work at long term in 97% of patients irrespectively of pacing indication, lead type, and lead service life, performance being superior with discordant pacing/sensing configurations. Atrial Capture Control could work in 93% of patients at 4.8 V maximum adapted voltage and at any pulse width, regardless of pacing indication, lead type, and service life. At 12-month follow-up, a ventricular threshold increase ≥1.5 V had occurred in 4.4% of patients uneventfully owing to VCC functioning. Projected pacemaker longevity at 1 month was strongly correlated with the 12-month estimate, and exceeded 13 years in >60% of patients. CONCLUSION: These algorithms for automatic management of pacing output ensure patient safety in the event of a huge increase of pacing threshold, while enabling maximization of battery longevity. Their applicability is quite broad in an unselected pacemaker population irrespectively of lead choice and service of life.

Left Ventricular Reverse Remodeling Elicited by a Quadripolar Lead: Results from the Multicenter Per4mer Study.

BACKGROUND: To understand the impact of a quadripolar left ventricular (LV) lead on reverse remodeling and phrenic nerve stimulation (PNS) in congestive heart failure patients treated by cardiac resynchronization therapy at 8-month follow-up (FU). METHODS: One hundred and fifty-eight patients received an LV Medtronic Performa lead (Medtronic Inc., Minneapolis, MN, USA) and were reevaluated at FU by echocardiography and measurement of electrical parameters. RESULTS: A targeted LV lead placement was achieved in 140 (89%) patients. Super responders and responders were 76 (50%) and 26 (18%), respectively, at FU; seven (4%) died and 13 (8%) were hospitalized for any cause. Nonischemic etiology was the only independent predictor of reverse remodeling. The configurations available only with the Performa leads reduced PNS occurrence at 8 V@0.4 ms from 43 (27%) to 14 (9%) of patients at implantation, and from 44 (28%) to 19 (12%) at last FU, compared to configurations available with bipolar leads. Patients with detectable PNS had >10/16 pacing configurations with a PNS safety margin >2 V both at implantation and at FU. During FU 16 (10%) patients had an adverse event possibly related to the lead or to modification of the underlying heart disease but 99% of these events were fixed by reprogramming of the pacing vector. CONCLUSIONS: Performa Lead enables an increased capability to achieve a targeted lead positioning in the broad clinical scenario of large- and small-volume implanting centers, with a relevant impact on the occurrence of reverse remodeling compared to literature data. The enhanced management of PNS resulted in a dislodgement rate of only 1%.

Assessment of a standardized algorithm for cardiac pacing in older patients affected by severe unpredictable reflex syncopes.

AIMS: Opinions differ regarding the effectiveness of cardiac pacing in patients affected by reflex syncope. We assessed a standardized guideline-based algorithm in different forms of reflex syncope. METHODS AND RESULTS: In this prospective, multi-centre, observational study, patients aged >40 years, affected by severe unpredictable recurrent reflex syncopes, underwent carotid sinus massage (CSM), followed by tilt testing (TT) if CSM was negative, followed by implantation of an implantable loop recorder (ILR) if TT was negative. Those who had an asystolic response to one of these tests received a dual-chamber pacemaker. POPULATION: 253 patients, mean age 70 ± 12 years, median 4 (3-6) syncopes, 89% without or with short prodromes. Of these patients, 120 (47%) received a pacemaker and 106 were followed up for a mean of 13 ± 7 months: syncope recurred in 10 (9%). The recurrence rate was similar in 61 CSM+ (11%), 30 TT+ (7%), and 15 ILR+ (7%) patients. The actuarial total syncope recurrence rate was 9% (95% confidence interval (CI), 6-12) at 1 year and 15% (95% CI, 10-20) at 2 years and was significantly lower than that observed in the group of 124 patients with non-diagnostic tests who had received an ILR: i.e. 22% (95% CI, 18-26) at 1 year and 37% (95% CI, 30-43) at 2 years (P = 0.004). CONCLUSION: About half of older patients with severe recurrent syncopes without prodromes have an asystolic reflex for which cardiac pacing goes along with a low recurrence rate. The study supports the clinical utility of the algorithm for the selection of candidates to cardiac pacing in everyday clinical practice. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov. Unique identifier: NCT01509534.

Implantation of single lead cardioverter defibrillator with floating atrial sensing dipole in a pregnant patient without using fluoroscopy.

In this case report, we look into the implant procedure of a single-lead ICD with floating atrial sensing dipole in a pregnant woman, without using fluoroscopy. This system benefits the proper positioning of the lead. This is possible thanks to the simultaneous display of both the atrial and ventricular dipoles on the electro-anatomical mapping system. This technique may be taken into consideration for the few rare cases where fluoroscopy is absolutely contraindicated.

Long-term clinical outcome of patients who failed catheter ablation of atrial fibrillation.

AIMS: Left atrial ablation fails to prevent symptomatic recurrences of atrial fibrillation (AF) in 20-30% of patients up to 3 years of follow-up despite multiple procedures. Data are lacking on the long-term clinical outcome of those patients for whom the decision was taken to renounce performing further ablation procedures. METHODS AND RESULTS: In this multicentre study, 218 (34%) of 631 consecutive patients, who had undergone AF catheter ablation in the years 2001-11 for drug-refractory symptomatic AF, had symptomatic AF recurrences after 1.5 ± 0.6 procedures. Their long-term clinical outcome was assessed in March 2012 (minimum follow-up 1 year). At a mean of 5.1 ± 2.6 years since their last ablation, 82 (38%) patients improved, 103 (47%) remained unchanged and 33 (15%) worsened, but only 17 (8%) had such a severe impairment of their quality of life as to require atrioventricular junction ablation and pacing (#13) or cardiac surgery (#4); 22 (10%) patients had had adverse clinical events (death in five, heart failure in five, stroke and transient ischaemic cerebral attack in four, severe haemorrhage in four, pacemaker or implantable cardioverter-defibrillator implantation in seven) and 98 (45%) patients had developed permanent AF. Compared with patients without permanent AF, fewer patients with permanent AF improved (3% vs. 66%, P = 0.001) and more got worse (28% vs. 5%, P = 0.001). At multivariable logistic regression, single ablation procedure, left atrial diameter, persistent AF and time from the last ablation were independent predictors of permanent AF. CONCLUSION: More than 5 years after a failed AF ablation, a small minority of patients had such an impaired quality of life as to require non-pharmacological interventions. Almost half developed permanent AF, which significantly impaired quality of life. Permanent AF was more common in patients who had left atrial enlargement, history of persistent AF, longer follow-up, and had performed a single ablation procedure, thus hypothesizing that reablation could reduce the chronicization of arrhythmia. A low risk of stroke was observed in the long-term follow-up.