Ablate and pace: Comparison of outcomes between conduction system pacing and biventricular pacing.

BACKGROUND: Conduction system pacing (CSP), including His-bundle pacing (HBP) and left bundle branch area pacing (LBBAP), have been proposed as alternatives to biventricular pacing (BVP) in patients scheduled for ablate and pace (A&P) strategy. The aim of this study was to compare the clinical outcomes, including the rate and nature of device-related complications, between BVP and CSP in a cohort of patients undergoing A&P. METHODS: Prospective, multicenter, observational study, enrolling consecutive patients undergoing A&P. The risk of device-related complications and of heart failure (HF) hospitalization was prospectively assessed. RESULTS: A total of 373 patients (75.3 ± 8.7 years, 53.9% male, 68.9% with NYHA class ≥III) were enrolled: 263 with BVP, 68 with HBP, and 42 with LBBAP. Baseline characteristics of the three groups were similar. Compared to BVP and HBP, LBBAP was associated with the shortest mean procedural and fluoroscopy times and with the lowest acute capture thresholds (all p < .05). At 12-month follow-up LBBAP maintained the lowest capture thresholds and showed the longest estimated residual battery longevity (all p < .05). At 12-months follow-up the three study groups showed a similar risk of device-related complications (5.7%, 4.4%, and 2.4% for BVP, HBP, and LBBAP, respectively; p = .650), and of HF hospitalization (2.7%, 1.5%, and 2.4% for BVP, HBP, and LBBAP, respectively; p = .850). CONCLUSIONS: In the setting of A&P, CSP is a feasible pacing modality, with a midterm safety profile comparable to BVP. LBBAP offers the advantage of reducing procedural times and obtaining lower and stable capture thresholds, with a positive impact on the device longevity.

Ablation of CTI-dependent flutter using different ablation technologies: acute and long-term outcome from the LEONARDO study.

BACKGROUND: A novel ablation catheter has been released to map and ablate the cavo-tricuspid isthmus (CTI) in patients with atrial flutter (AFL), improving ablation efficiency. METHODS: We evaluated the acute and long-term outcome of CTI ablation aiming at bidirectional conduction block (BDB) in a prospective, multicenter cohort study enrolling 500 patients indicated for typical AFL ablation. Patients were grouped on the basis of the AFL ablation method (linear anatomical approach, Conv group n = 425, or maximum voltage guided, MVG group, n = 75) and ablation catheter (mini-electrodes technology, MiFi group, n = 254, or a standard 8-mm ablation catheter, BLZ group, n = 246). RESULTS: Complete BDB according to both validation criteria (sequential detailed activation mapping or mapping only the ablation site) was achieved in 443 patients (88.6%). The number of RF applications needed to achieve BDB was lower in the MiFi MVG group vs both the MiFi Conv group and the BLZ Conv group (3.2 ± 2 vs 5.2 ± 4 vs 9.3 ± 5, p < 0.0001 for all comparisons). Fluoroscopy time was similar among groups, whereas we observed a reduction in the procedure duration from the BLZ Conv group (61.9 ± 26min) to the MiFi MVG group (50.6 ± 17min, p = 0.048). During a mean follow-up of 548 ± 304 days, 32 (6.2%) patients suffered an AFL recurrence. No differences were found according to BDB achieved by both validation criteria. CONCLUSIONS: Ablation was highly effective in achieving acute CTI BDB and long-term arrhythmia freedom irrespective of the ablation strategy or the validation criteria for CTI chosen by the operator. The use of an ablation catheter equipped with mini-electrodes technology seems to improve ablation efficiency. CLINICAL TRIAL REGISTRATION: Atrial Flutter Ablation in a Real World Population. (LEONARDO). CLINICALTRIALS: gov Identifier: NCT02591875.

Effectiveness and safety of implantable loop recorder and clinical utility of remote monitoring in patients with unexplained, recurrent, traumatic syncope.

BACKGROUND: Implantable loop recorder (ILR) is still underutilized in clinical practice, especially in the setting of elderly patients with recurrent, traumatic, unexplained syncope. Data on the actual risk of traumatic syncopal recurrence during ILR monitoring in this specific patient setting are lacking. RESEARCH DESIGN AND METHODS: Prospective, multicentre registry enrolling consecutive patients undergoing ILR insertion for unexplained, recurrent, traumatic syncope. In a proportion of enrolled patients, remote monitoring (RM) was used for device follow-up. The risk of traumatic and non-traumatic syncopal recurrences during ILR observation were prospectively assessed. RESULTS: A total of 483 consecutive patients (68±14 years, 59% male) were enrolled. During a median follow-up of 18 months, a final diagnosis was reached in 270 patients (55.9%). The risk of syncopal and traumatic syncopal recurrence was of 26.5 and 9.3%, respectively. RM significantly reduced the time to diagnosis (19.7±10.3 vs. 22.1±10.8 months; p=0.015) and was associated with a significant reduction in the risk of syncope recurrence of 48% (p<0.001), and of traumatic syncope recurrence of 49% (p=0.018). CONCLUSIONS: ILR monitoring is effective and safe in patients with unexplained, recurrent, traumatic syncope. RM reduces the time to diagnosis and significantly reduces the risk of traumatic and non-traumatic syncopal relapses.

Management of older patients with unexplained, recurrent, traumatic syncope and bifascicular block: Implantable loop recorder versus empiric pacemaker implantation-Results of a propensity-matched analysis.

BACKGROUND: In patients with unexplained syncope and bifascicular block (BFB), syncope may be caused by intermittent atrioventricular (AV) block. When a correlation between syncope and bradyarrhythmia is not documented in these patients, 2 alternative management strategies can be adopted: (1) empiric pacemaker (PM) implantation or (2) long-term continuous electrocardiographic monitoring by implantable loop recorder (ILR). OBJECTIVE: The purpose of this study was to compare the risk of syncope recurrence associated with empiric PM implantation or ILR monitoring. METHODS: A prospective, multicenter, observational study enrolled consecutive patients with unexplained, recurrent, traumatic syncope and BFB who underwent ILR monitoring or empiric PM implantation. The risk and causes of syncope recurrence were assessed and compared between the 2 groups. Individual 1:1 propensity matching of baseline characteristics was performed. RESULTS: A total of 309 consecutive patients (age 77.2 ± 12.2 years; 60.8% male) were enrolled. Propensity matching yielded 89 matched pairs. After median follow-up of 33 months, empiric PM implantation was associated with a significantly lower risk of syncope recurrence than ILR monitoring (19.1 vs 46.1%; P <.001). A total of 35 patients (39.3%) who underwent ILR monitoring developed bradyarrhythmias (68.6% paroxysmal AV block) requiring PM implantation during follow-up. Excluding bradyarrhythmic syncope, the most frequent causes of syncope recurrence in both study groups were reflex syncope and orthostatic hypotension. CONCLUSION: In patients with unexplained, recurrent, traumatic syncope and BFB, empiric PM implantation significantly reduced the risk of syncope recurrence in comparison with ILR monitoring. A high rate of patients who underwent ILR monitoring developed bradyarrhythmias requiring PM implantation.

Effect of SAcubitril/Valsartan on left vEntricular ejection fraction and on the potential indication for Implantable Cardioverter Defibrillator in primary prevention: the SAVE-ICD study.

PURPOSE: Sacubitril/valsartan has been associated with a positive reverse left ventricular remodelling in patients with heart failure with reduced ejection fraction (HFrEF). These patients may also benefit from an ICD implant. We aimed to assess EF improvement after 6 months of treatment with sacubitril/valsartan, evaluating when ICD as primary prevention was no longer indicated. METHODS: Multicentre, observational, prospective study enrolling all consecutive patients with HFrEF and EF ≤ 35% with an ICD as primary prevention and starting treatment with sacubitril/valsartan (NCT03935087). Resynchronization therapy and patients experiencing appropriate ICD therapies before sacubitril/valsartan were excluded. RESULTS: Two-hundred-and-thirty patients were enrolled (73.9% males, mean age 64.3 ± 12.1 years) After 6 months of treatment, a reduction in left ventricular end-diastolic and end-systolic volumes was noted and LVEF increased from 28.3 ± 5.6% to 32.2 ± 6.5% (p < 0.001). At 6 months, a non-ischemic aetiology of cardiomyopathy and a final dose of sacubitril/valsartan > 24/26 mg twice daily were associated with a higher probability of an absolute increase of > 5% in LVEF. A total of 5.3% of primary prevention patients still had an arrhythmic event in the first 6 months after treatment with sacubitril/valsartan started. CONCLUSIONS: Sacubitril/valsartan improves systolic function in HFrEF, mainly due to reverse left ventricular remodelling. Improvement in EF after 6 months of treatment could help prevent ICD implantation in nearly one out of four patients, with important clinical and economic implications. However, the risk of sudden cardiac death in this recovered HFrEF population has not been thoroughly studied, and the present data should be interpreted only as hypothesis-generating.

Causes of syncopal recurrences in patients treated with permanent pacing for bradyarrhythmic syncope: Findings from the SYNCOPACED registry.

BACKGROUND: Few studies have examined the causes of syncope/collapse recurrences in patients with a previously implanted pacemaker for bradyarrhythmic syncope. OBJECTIVE: The purpose of this study was to assess the causes of syncope/collapse recurrences after pacemaker implantation for bradyarrhythmic syncope in a large patient population. METHODS: The SYNCOpal recurrences in patients treated with permanent PACing for bradyarrhythmic syncope (SYNCOPACED) registry was a prospective multicenter observational registry enrolling 1364 consecutive patients undergoing pacemaker implantation for bradyarrhythmic syncope. During follow-up, the time to the first syncope/collapse recurrence was recorded. Patients with syncope/collapse recurrences underwent a predefined diagnostic workup aimed at establishing the mechanism of syncope/collapse. RESULTS: During a median follow-up of 50 months, 213 patients (15.6%) reported at least 1 syncope/collapse recurrence. The risk of syncope/collapse recurrence was highest in patients who underwent implantation for cardioinhibitory vasovagal syncope (26.4%), followed by unexplained syncope and chronic bifascicular block (21.5%), cardioinhibitory carotid sinus syndrome (17.2%), atrial fibrillation needing pacing (15.5%), atrioventricular block (13.6%), and sinus node disease (12.5%) (P = .017). The most frequent cause of syncope/collapse recurrence was reflex syncope (27.7%), followed by orthostatic hypotension (26.3%), pacemaker or lead malfunction (5.6%), structural cardiac disease (5.2%), and atrial and ventricular tachyarrhythmias (4.7% and 3.8%, respectively). In 26.8% of cases, the mechanism of syncope/collapse remained unexplained. CONCLUSION: In patients receiving a pacemaker for bradyarrhythmic syncope, reflex syncope and orthostatic hypotension are the most frequent mechanisms of syncope/collapse recurrence after implantation. Pacing system malfunction, structural cardiac diseases, and tachyarrhythmias are rare mechanisms. The mechanism remains unexplained in >25% of patients.

Risk of syncopal recurrences in patients treated with permanent pacing for bradyarrhythmic syncope: role of correlation between symptoms and electrocardiogram findings.

AIMS: To evaluate the risk of syncopal recurrences after pacemaker implantation in a population of patients with syncope of suspected bradyarrhythmic aetiology. METHODS AND RESULTS: Prospective, multicentre, observational registry enrolling 1364 consecutive patients undergoing pacemaker implantation for syncope of bradyarrhythmic aetiology (proven or presumed). Before pacemaker implantation, all patients underwent a cardiac work-up in order to establish the bradyarrhythmic aetiology of syncope. According to the results of the diagnostic work-up, patients were divided into three groups: Group A, patients in whom a syncope-electrocardiogram (ECG) correlation was established (n = 329, 24.1%); Group B, those in whom clinically significant bradyarrhythmias were detected without a documented syncope-ECG correlation (n = 877, 64.3%); and Group C, those in whom bradyarrhythmias were not detected and the bradyarrhythmic origin of syncope remained presumptive (n = 158, 11.6%). During a median follow-up of 50 months, 213 patients (15.6%) reported at least one syncopal recurrence. Patients in Groups B and C showed a significantly higher risk of syncopal recurrences than those in Group A [hazard ratios (HRs): 1.60 and 2.66, respectively, P < 0.05]. Failure to establish a syncope-ECG correlation during diagnostic work-up before pacemaker implantation was an independent predictor of syncopal recurrence on multivariate analysis (HR: 1.90; P = 0.002). CONCLUSION: In selecting patients with syncope of suspected bradyarrhythmic aetiology for pacemaker implantation, establishing a correlation between syncope and bradyarrhythmias maximizes the efficacy of pacing and reduces the risk of syncopal recurrences.

Long-term progression of rhythm and conduction disturbances in pacemaker recipients: findings from the Pacemaker Expert Programming study.

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 ±â€Š13.3 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.

Physical Activity Measured by Implanted Devices Predicts Atrial Arrhythmias and Patient Outcome: Results of IMPLANTED (Italian Multicentre Observational Registry on Patients With Implantable Devices Remotely Monitored).

BACKGROUND: To determine whether daily physical activity (PA), as measured by implanted devices (through accelerometer sensor), was related to the risk of developing atrial arrhythmias during long-term follow-up in a population of heart failure (HF) patients with an implantable cardioverter defibrillator (ICD). METHODS AND RESULTS: The study population was divided into 2 equally sized groups (PA cutoff point: 3.5 h/d) according to their mean daily PA recorded by the device during the 30- to 60-day period post-ICD implantation. Propensity score matching was used to compare 2 equally sized cohorts with similar characteristics between lower and higher activity patients. The primary end point was time free from the first atrial high-rate episode (AHRE) of duration ≥6 minutes. Secondary end points were: first AHRE ≥6 hours, first AHRE ≥48 hours, and a combined end point of death or HF hospitalization. Data from 770 patients (65±15 years; 66% men; left ventricular ejection fraction 35±12%) remotely monitored for a median of 25 months were analyzed. A PA ≥3.5 h/d was associated with a 38% relative reduction in the risk of AHRE ≥6 minutes (72-month cumulative survival: 75.0% versus 68.1%; log rank P=0.025), and with a reduction in the risk of AHRE ≥6 hours, AHRE ≥48 hours, and the combined end point of death or HF hospitalization (all P<0.05). CONCLUSIONS: In HF patients with ICD, a low level of daily PA was associated with a higher risk of atrial arrhythmias, regardless of the patients' baseline characteristics. In addition, a lower daily PA predicted death or HF hospitalization.

Effect of fixed-rate vs. rate-RESPONSIve pacing on exercise capacity in patients with permanent, refractory atrial fibrillation and left ventricular dysfunction treated with atrioventricular junction aBLation and bivEntricular pacing (RESPONSIBLE): a prospective, multicentre, randomized, single-blind study.

AIMS: Atrioventricular junction (AVJ) ablation followed by biventricular pacing is an established strategy for improving symptoms and morbidity in patients with permanent atrial fibrillation (AF), reduced left ventricular ejection fraction (LVEF), and uncontrolled ventricular rate. There is no clear evidence that such patients benefit from rate-responsive (RR) pacing. METHODS AND RESULTS: This prospective, randomized, single-blind, multicentre study was designed as an intra-patient comparison and enrolled 60 patients (age 69.5 ± 11.8 years, males 63.3%, NYHA 3.0 ± 0.6) with refractory AF and reduced LVEF (mean 32.4 ± 8.3%) treated with AVJ ablation and biventricular pacing. Two 6-minute walking tests (6MWT) were performed 1 week apart: one during VVI 70/min biventricular pacing and the other during VVIR 70-130/min biventricular pacing; patients were randomly and blindly assigned to Group A (n = 29, first 6MWT in VVIR mode) or B (n = 31, first 6MWT in VVI mode). Rate-responsive activation determined an increase of 18.8 ± 24.4 m in the distance walked during the 6MWT (P < 0.001). The increase was similar in both groups (P = 0.571). A >5% increase in the distance walked was observed in 76.7% of patients. The increase in the distance walked was linearly correlated with the increase in heart rate recorded during the 6MWT in the VVIR mode (r = 0.54; P < 0.001). CONCLUSION: In permanent AF patients with uncontrolled rate and reduced LVEF who had undergone AVJ ablation and biventricular pacing, RR pacing yields a significant gain in exercise capacity, which seems to be related to the RR-induced frequency during effort.

Clinically guided pacemaker choice and setting: pacemaker expert programming study.

AIM: The aim of this multicentre, observational, transversal study was to evaluate pacemaker (PM) choice and setting in a large number of patients, in order to understand their relationship with the patients' clinical characteristics. METHODS AND RESULTS: The study enrolled a total of 1858 patients (71 ± 14 years, 54% male), consecutively evaluated during scheduled PM follow-up visits in 7 Italian cardiac arrhythmia centres. To evaluate the appropriateness of PM choice in relation to the patients' clinical characteristics, we analysed their rhythm disorders at the time of device implantation and the characteristics of the devices implanted. To evaluate the appropriateness of device setting, current rhythm disorders and device setting at the time of enrolment were analysed. In the overall study population, 64.3% of the patients received a PM with all of the features required for their rhythm disorder [80.8% in persistent atrioventricular (AV) block, 76.5% in atrial fibrillation needing pacing, 71.0% in sinus node disease, 58.7% in non-persistent atrioventricular block (AVB), 52.7% in neuro-mediated syncope]. The most frequent cause of inappropriate PM choice was the lack of an algorithm to promote intrinsic AV conduction in non-persistent AVB patients (38.1%). In 76.2% of the patients with an appropriate PM (n = 1301), the PM was optimally set for their rhythm disorder. CONCLUSIONS: In the present 'real-world' registry, a large number of patients (35.7%) did not receive an optimal PM for their rhythm disorders. Moreover, one-fourth of appropriate PMs were not programmed according to the patients' clinical characteristics.